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Ethnopharmacological Relevance: HLA-B*35:01 has been identified as a risk allele for Polygonum multiflorum Thunb.-induced liver injury (PMLI). However, the immune mechanism underlying HLA-B*35:01-mediated PMLI remains unknown., Aim of the Study: To characterize the immune mechanism of HLA-B*35:01-mediated PMLI., Materials and Methods: Components of P. multiflorum (PM) bound to the HLA-B*35:01 molecule was screened by immunoaffinity chromatography. Both wild-type mice and HLA-B*35:01 transgenic (TG) mice were treated with emodin. The levels of transaminases, histological changes and T-cell response were assessed. Splenocytes from emodin-treated mice were isolated and cultured in vitro. Phenotypes and functions of T cells were characterized upon drug restimulation using flow cytometry or ELISA. Emodin-pulsed antigen-presenting cells (APCs) or glutaraldehyde-fixed APCs were co-cultured with splenocytes from emodin-treated transgenic mice to detect their effect on T-cell activation., Results: Emodin, the main component of PM, could non-covalently bind to the HLA-B*35:01-peptide complexes. TG mice were more sensitive to emodin-induced immune hepatic injury, as manifested by elevated aminotransferase levels, infiltration of inflammatory cells, increased percentage of CD8+T cells and release of effector molecules in the liver. However, these effects were not observed in wild-type mice. An increase in percentage of T cells and the levels of interferon-γ, granzyme B, and perforin was detected in emodin-restimulated splenocytes from TG mice. Anti-HLA-I antibodies inhibited the secretion of these effector molecules induced by emodin. Mechanistically, emodin-pulsed APCs failed to stimulate T cells, while fixed APCs in the presence of emodin could elicit the secretion of T cell effector molecules., Conclusion: The HLA-B*35:01-mediated CD8 + T cell reaction to emodin through the P-I mechanism may contribute to P. multiflorum-induced liver injury., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest regarding the publication of this article., (Copyright © 2024 Elsevier B.V. All rights reserved.)

BACKGROUNDInhibition of Bruton's tyrosine kinase with ibrutinib blocks the function of myeloid-derived suppressor cells (MDSC). The combination of ibrutinib and nivolumab was tested in patients with metastatic solid tumors.METHODSSixteen patients received ibrutinib 420 mg p.o. daily with nivolumab 240 mg i.v. on days 1 and 15 of a 28-day cycle. The effect of ibrutinib and nivolumab on MDSC, the immune profile, and cytokine levels were measured. Single-cell RNA-Seq and T cell receptor sequencing of immune cells was performed.RESULTSCommon adverse events were fatigue and anorexia. Four patients had partial responses and 4 had stable disease at 3 months (average 6.5 months, range 3.5-14.6). Median overall survival (OS) was 10.8 months. Seven days of Bruton's tyrosine kinase (BTK) inhibition significantly increased the proportion of monocytic-MDSC (M-MDSC) and significantly decreased chemokines associated with MDSC recruitment and accumulation (CCL2, CCL3, CCL4, CCL13). Single-cell RNA-Seq revealed ibrutinib-induced downregulation of genes associated with MDSC-suppressive function (TIMP1, CXCL8, VEGFA, HIF1A), reduced MDSC interactions with exhausted CD8+ T cells, and decreased TCR repertoire diversity. The addition of nivolumab significantly increased circulating NK and CD8+ T cells and increased CD8+ T cell proliferation. Exploratory analyses suggest that MDSC and T cell gene expression and TCR repertoire diversity were differentially affected by BTK inhibition according to patient response.CONCLUSIONIbrutinib and nivolumab were well tolerated and affected MDSC and T cell function in patients with solid metastatic tumors.TRIAL REGISTRATIONClinicalTrials.gov NCT03525925.FUNDINGNIH; National Cancer Institute Cancer; National Center for Advancing Translational Sciences; Pelotonia.

Intratumoral regulatory T cells (Tregs) express high levels of CD25 and TIGIT, which are also recognized as markers of effector T cell (Teff) activation. Targeting these molecules each alone with monoclonal antibodies (mAbs) poses a risk of concurrently depleting both Teffs and peripheral Tregs, thereby compromising the effectiveness and selectivity of intratumoral Treg depletion. Here, leveraging the increased abundance of CD25 + TIGIT + double-positive Tregs in the solid tumor microenvironment (but not in peripheral tissues), we explore the feasibility of using a CD25×TIGIT bispecific antibody (bsAb) to selectively deplete intratumoral Tregs. We initially constructed a bsAb co-targeting mouse CD25 and TIGIT, NSWm7210, and found that NSWm7210 conferred enhanced intratumoral Treg depletion, Teff activation, and tumor suppression as compared to the parental monotherapies in mouse models. We subsequently constructed a bsAb co-targeting human CD25 and TIGIT (NSWh7216), which preferentially eliminated CD25 + TIGIT + double-positive cells over single-positive cells in vitro. NSWh7216 exhibited enhanced anti-tumor activity without toxicity of peripheral Tregs in CD25 humanized mice compared to the parental monotherapies. Our study illustrates the use of CD25×TIGIT bsAbs as effective agents against solid tumors based on selective depletion of intratumoral Tregs., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objective: The Drug Lymphocyte Stimulation Test (DLST), recognized for its safety as an allergy diagnostic modality, has been acknowledged for its utility in diagnosing drug-induced pathological conditions. However, reports elucidating DLST outcomes concerning local anesthetics are notably scarce., Materials and Methods: An exhaustive analysis was conducted on the DLST results pertaining to local anesthetics derived from 571 patients presenting with suspected allergies to these specific agents., Results: Remarkably, Stimulation Index (SI) > 1.8 was discerned in 11.4% and 7.8% of patients exhibiting hives or swelling subsequent to the administration of local anesthetics, surpassing the incidence observed in those experiencing post-injection discomfort. Additionally, SI > 3.0 was observed in 3 cases with lidocaine, 3 cases with prilocaine, and 1 case with mepivacaine. The distribution of SI exhibited a non-normal pattern for all three tested local anesthetics. Noteworthy is the case of a singular patient registering an SI of 1.84, who also yielded a positive challenge test, conclusively confirming an allergy to lidocaine., Conclusions: The DLST, holding promise as a potentially invaluable tool in identifying the causative factors behind adverse reactions to dental local anesthetics, lacks sufficient evidence to substantiate its efficacy definitively at present., Clinical Relevance: DLST, coupled with intradermal testing and challenge testing, may be elucidated in patients exhibiting indicators of suspected local anesthetic allergy., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction: Regulatory CD8 T cells (CD8 Treg) are responsible for the selective killing of self-reactive and pathogenic CD4 T cells. In autoimmune disease, CD8 Treg may accumulate in the peripheral blood but fail to control the expansion of pathogenic CD4 T cells that subsequently cause tissue destruction. This CD8 Treg dysfunction is due in part to the expression of inhibitory killer immunoglobulin-like receptors (KIR; KIR2DL isoforms [KIR2DL1, KIR2DL2, and KIR2DL3]); these molecules serve as autoimmune checkpoints and limit CD8 Treg activation., Methods: Here we describe the pre-clinical characterization of MTX-101, a bispecific antibody targeting inhibitory KIR and CD8. Using human peripheral blood mononuculear cells (PBMC) derived from healthy donors and autoimmune patients, humanized mouse models, and human derived tissue organoids, we evaluated the molecular mechanisms and functional effects of MTX-101., Results: By binding to KIR, MTX-101 inhibited KIR signaling that can restore CD8 Treg ability to eliminate pathogenic CD4 T cells. MTX-101 bound and activated CD8 Treg in human peripheral blood mononuclear cells (PBMC), resulting in increased CD8 Treg cytolytic capacity, activation, and prevalence. Enhancing CD8 Treg function with MTX-101 reduced pathogenic CD4 T cell expansion and inflammation, without increasing pro-inflammatory cytokines or activating immune cells that express either target alone. MTX-101 reduced antigen induced epithelial cell death in disease affected tissues, including in tissue biopsies from individuals with autoimmune disease (i.e., celiac disease, Crohn's disease). The effects of MTX-101 were specific to autoreactive CD4 T cells and did not suppress responses to viral and bacterial antigens. In a human PBMC engrafted Graft versus Host Disease (GvHD) mouse model of acute inflammation, MTX-101 bound CD8 Treg and delayed onset of disease. MTX-101 induced dose dependent binding, increased prevalence and cytolytic capacity of CD8 Treg, as well as increased CD4 T cell death. MTX-101 selectively bound CD8 Treg without unwanted immune cell activation or increase of pro-inflammatory serum cytokines and exhibited an antibody-like half-life in pharmacokinetic and exploratory tolerability studies performed using IL-15 transgenic humanized mice with engrafted human lymphocytes, including CD8 Treg at physiologic ratios., Conclusion: Collectively, these data support the development of MTX-101 for the treatment of autoimmune diseases., Competing Interests: The authors were employed by Mozart Therapeutics and declare that the study was funded by Mozart Therapeutics. Mozart Therapeutics was involved in the study design, collection, analysis, interpretation of data, the writing of this article, and the decision to submit it for publication., (Copyright © 2024 Gardell, Maurer, Childs, Pham, Meengs, Julien, Tan, Boster, Quach, Therriault, Hermansky, Patton, Bowser, Chen, Morgan, Gilbertson, Bogatzki, Encarnacion, McMahan, Crane and Swiderek.)

Background: Glycolysis is crucial for tumor cell proliferation, supporting their energy needs and influencing the tumor microenvironment (TME). On one hand, increased lactate levels produced by glycolysis acidifies the TME, inhibiting T cell activity. On the other hand, glycolysis promotes the expression of PD-L1 through various mechanisms, facilitating immune evasion. Therefore, controlled modulation of glycolysis in tumor cells to subsequently improve the immune tumor microenvironment holds significant implications for clinical cancer treatment and immune regulation., Methods: To reverse the immunosuppressive microenvironment caused by tumor glycolysis and reduce tumor immune escape, we developed a photo-thermal-controlled precision drug delivery platform to regulate tumor metabolism and aid in the activation of T cells, thereby enhancing immunotherapy. First, hollow mesoporous Prussian blue (HPB) was prepared, and the glycolysis inhibitor 3-bromopyruvate (3-BrPA) was encapsulated within HPB using the phase-change material 1-tetradecanol, resulting in B/T-H. This product was then modified with tumor cell membranes to obtain a photo-thermal controllable regulator (B/T-H@Membrane, B/T-HM)., Results: Due to the excellent drug loading and photo-thermal properties of HPB, upon reaching the tumor, B/T-HM can rapidly heat under 808 nm irradiation, causing the 1-tetradecanol to transition to a liquid phase and release 3-BrPA, which effectively inhibits tumor glycolysis through the HK2 pathway, thereby reducing tumor cell proliferation, decreasing lactate production, and downregulating tumor PD-L1 expression. In synergy with photo-thermal and αPD-1, this photo-thermally controllable metabolic-immune therapy effectively activates T cells to eliminate tumor., Conclusion: In response to the changes in immune microenvironment caused by tumor metabolism, a photo-thermal precision-controlled drug delivery platform was successfully developed. This platform reshapes the tumor immunosuppressive microenvironment, providing a new approach for T cell-based tumor immunotherapy. It also opens new avenues for photo-thermal controllable metabolic-immune therapy., Competing Interests: The authors declare no conflict of interests in this work., (© 2024 Ma et al.)

Sialic acids at the cell surface of dendritic cells (DCs) play an important immunomodulatory role, and their manipulation enhances DC maturation, leading to heightened T cell activation. Particularly, at the molecular level, the increased stability of surface MHC-I molecules in monocyte-derived DCs (MoDCs) underpins an improved DC: T cell interaction. In this study, we focused on the impact of sialic acid remodelling by treatment with Clostridium perfringens sialidase on MoDCs' phenotypic and functional characteristics. Our investigation juxtaposes this novel approach with the conventional cytokine-based maturation regimen commonly employed in clinical settings.Notably, C. perfringens sialidase remarkably increased MHC-I levels compared to other sialidases having different specificities, supporting the idea that higher MHC-I is due to the cleavage of specific sialoglycans on cell surface proteins. Sialidase treatment induced rapid elevated surface expression of MHC-I, MHC-II and CD40 within an hour, a response not fully replicated by 48 h cytokine cocktail treatment. These increases were also observable 48 h post sialidase treatment. While CD86 and PD-L1 showed significant increases after 48 h of cytokine maturation, 48 h post sialidase treatment showed a higher increase in CD86 and shorter increase in PD-L1. CCR-7 expression was significantly increased 48 h after sialidase treatment but not significantly affected by cytokine maturation. Both treatments promoted higher secretion of the IL-12 cytokine. However, the cytokine cocktail induced a more pronounced IL-12 production. SNA lectin staining analysis demonstrated that the sialic acid profile is significantly altered by sialidase treatment, but not by the cytokine cocktail, which causes only slight sialic acid upregulation. Notably, the lipid-presenting molecules CD1a, CD1b and CD1c remained unaffected by sialidase treatment in MoDCs, a finding also further supported by experiments performed on C1R cells. Inhibition of endogenous sialidases Neu1 and Neu3 during MoDC differentiation did not affect surface MHC-I expression and cytokine secretion. Yet, sialidase activity in MoDCs was minimal, suggesting that sialidase inhibition does not significantly alter MHC-I-related functions. Our study highlights the unique maturation profile induced by sialic acid manipulation in MoDCs. These findings provide insights into the potential of sialic acid manipulation as a rapid immunomodulatory strategy, offering promising avenues for targeted interventions in inflammatory contexts., (© 2024. The Author(s).)

Alemtuzumab induction with belatacept/rapamycin-based maintenance immunotherapy (ABR) prevents kidney allograft rejection and specifically limits early costimulation blockade-resistant rejection (CoBRR). To evaluate the mechanisms by which this regimen alters CoBRR, we characterized the phenotype and functional response of preexisting memory cells to allogeneic endothelial cells using intracellular cytokine staining and flow cytometry. IL-7-induced lymphocyte proliferation in the presence or absence of rapamycin was assessed to characterize the phenotype of proliferating cells. Lymphocytes from 40 recipients who underwent transplant using the ABR regimen were studied longitudinally. The rapid immunoresponses of preexisting alloreactive cells to allogeneic endothelial cells were predominantly CD8+TNF-α+/IFN-γ+ cells. These cells were effector memory (TEM) and terminally differentiated effector memory cells lacking CD28 expression, and most were CD57+PD1-. Neither rapamycin nor belatacept directly inhibited these cells. IL-7, a cytokine induced during lymphopenia postdepletion, provoked dramatic CD8+ TEM cell proliferation and a low level of CD8+CD57+PD1- cell expansion in vitro. The IL-7 stimulation induced CD8+ cell mTOR phosphorylation, and rapamycin treatment markedly inhibited IL-7-induced TEM and CD57+PD1- cell expansion. This effect was evident in patients receiving the ABR in that the repopulation of CD8+CD57+PD1- TEM cells was substantially suppressed for at least 36 mo after transplant. These findings help define one mechanism by which a costimulation blockade/rapamycin-based therapy following alemtuzumab induction minimizes CoBRR, namely that in the presence of rapamycin, costimulation-resistant alloreactive cells are disproportionately ineffective at repopulating following post-transplant T cell depletion., (Copyright © 2024 by The American Association of Immunologists, Inc.)

A growing body of clinical and experimental evidence indicates that immune checkpoint blockade enhances patient susceptibility to hypersensitivity reactions to co-administered medications. In this study, we utilized an in vitro T-cell priming assay to demonstrate one of the mechanistic hypotheses on how this occurs; through lowering of the threshold in patients to elicit aberrant T-cell responses. We outline the dependency of de novo T-cell priming responses to drug-associated antigens on dose at initial exposure. Findings support the aforementioned hypothesis and offer an experimental representation of fundamental parameters at play in hypersensitivity reactions to low molecular weight compounds., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society of Toxicology.)

UFMylation, a novel ubiquitin-like protein modification system, has been recently found to be activated in inflammation. However, the effects of UFMylation activation on inflammation in vivo remains unclear. In the present study, we generated a UFMylation activated mice using transgenic (TG) techniques. Lipopolysaccharide (LPS) was used to induce systemic inflammation in both TG and non-transgenic (NTG) mice. Serum cytokines were detected using a Mouse Cytokine Array, and the proportions of splenic NK, B and T cells were determined by using flow cytometry. We found that TG mice showed increased serum G-CSF, TNF RII and decreased serum TCA-3, CD30L, bFGF, IL-15 and MIG compared with NTG mice at baseline. Furthermore, serum cytokines in TG mice exhibited different responses to LPS compared to NTG mice. LPS up-regulated serum TNF RII, G-CSF, MCP-5, RANTES, KC, BLC, MIG and down-regulated IL-1b, IL-2, IL-3, IL-4, IL-5, IL-7, IL-10, IL-12p40, IL-15, IL-17, IFN-γ, TCA-3, Eotaxin-2, LIX, MCP-1, TNFα, GM-CSF in NTG mice, whereas LPS up-regulated G-CSF, MCP-5, RANTES, KC, BLC, MIG, ICAM-1, PF4, Eotaxin, CD30L, MIP-1a, TNFRI and down-regulated IL-1b, IL-3, LIX, MCP-1, TNFα, GM-CSF in TG mice. Data from flow cytometry indicated that LPS significantly reduced the percentages of NK and NKT cells in NTG mice, whereas UFMylation activation inhibited LPS-induced NKT cell decrease. The proportions of B cells, total CD4 + and total CD8 + T cells were comparable between TG and NTG mice in response to LPS treatment, whereas the percentages of CD4 + CD69 + and CD8 + CD69 + T cells were lower in TG mice. These findings suggest that UFMylation may alter LPS-induced serum cytokine profile and participate in splenic T cell activation in vivo., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The ability to remotely control the activity of chimeric antigen receptors (CARs) with small molecules can improve the safety and efficacy of gene-modified T cells. Split ON- or OFF-switch CARs involve the dissociation of tumor-antigen binding from T cell activation (i.e., CD3ζ) on the receptor (R-) and signaling (S-) chains, respectively, that either associate or are disrupted in the presence of a small molecule. Here, we have developed an inducible (i)ON-CAR comprising the anti-apoptotic B cell lymphoma protein 2 protein in the ectodomain of both chains which associate in the presence of venetoclax. We showed that inducible ON (iON)-CAR T cells respond to target tumors cells in the presence of venetoclax or the BH3 mimetic navitoclax in a dose-dependent manner, while there is no impact of the drugs on equivalent second generation-CAR T cells. Within 48 h of venetoclax withdrawal, iON-CAR T cells lose the ability to respond to target tumor cells in vitro as evaluated by Interferon-gamma (IFNγ) production, and they are reliant upon the presence of venetoclax for in vivo activity. Finally, by fusing a degron sequence to the endodomain of the iON-CAR S-chain we generated an all-in-one ON/OFF-switch CAR, the iONØ-CAR, down-regulated by lenalidomide within 4 to 6 for functionally inactive T cells (no IFNγ production) within 24 h. We propose that our remote-control CAR designs can reduce toxicity in the clinic. Moreover, the periodic rest of iON and iONØ-CAR T cells may alleviate exhaustion and hence augment persistence and long-term tumor control in patients., Competing Interests: Competing interests statement:Provisional intellectual property filing has been filed for iON and iONØ CAR designs with inventors including G.M.P.G.A., B.E.C., SS., and M.I.

Lentinula edodes polysaccharides are natural immunomodulators. SeLe30, analyzed in this study, is a new mixture of selenium-enriched linear 1,4-α-glucans and 1,3-β- and 1,6-β-glucans isolated from L. edodes mycelium. In the present study, we evaluated its immunomodulatory properties in human T cells. Peripheral blood mononuclear cells (PBMCs) and T cells were isolated from healthy donors' buffy coats. The effects of SeLe30 on CD25, CD366, and CD279 expression, the subsets of CD8+ T cells, and IFN-γ, IL-6, and TNF-α production were analyzed. SeLe30 downregulated CD25, CD279, and CD366 expression on T cells stimulated by the anti-CD3 antibody (Ab) and upregulated in unstimulated and anti-CD3/CD28-Abs-stimulated T cells. It increased the percentage of central memory CD8+ T cells in unstimulated PBMCs and naïve and central memory T cells in anti-CD3-Ab-stimulated PBMCs. SeLe30 decreased the number of central memory and naïve CD8+ T cells in anti-CD3/CD28-stimulated T cells, whereas, in PBMCs, it reduced the percentage of effector memory CD8+ T cells. Moreover, SeLe30 upregulated cytokine production. SeLe30 exhibits context-dependent effects on T cells. It acts on unstimulated T cells, affecting their activation while increasing the expression of immune checkpoints, which sensitizes them to inhibitory signals that can silence this activation. In the case of a lack of costimulation, SeLe30 exhibits an inhibitory effect, reducing T-cell activation. In cells stimulated by dual signals, its effect is further enhanced, again increasing the "safety brake" of CD366 and CD279. However, the final SeLe30 effect is mediated by its indirect impacts by altering interactions with other immune cells.

Immunity has shown potentials in informing drug development for cardiometabolic diseases, such as type 2 diabetes (T2D) and coronary artery disease (CAD). Here, we performed a transcriptome-wide Mendelian randomization (MR) study to estimate the putative causal effects of 11,021 gene expression profiles during CD4 + T cells activation on the development of T2D and CAD. Robust MR and colocalization evidence was observed for 162 genes altering T2D risk and 80 genes altering CAD risk, with 12% and 16% respectively demonstrating CD4 + T cell specificity. We observed temporal causal patterns during T cell activation in 69 gene-T2D pairs and 34 gene-CAD pairs. These genes were eight times more likely to show robust genetic evidence. We further identified 25 genes that were targets for drugs under clinical investigation, including LIPA and GCK. This study provides evidence to support immune-to-metabolic disease connections, and prioritises immune-mediated drug targets for cardiometabolic diseases., (© 2024. The Author(s).)

ABL602 2 + 1, a bispecific antibody with two distinct domains binding to CLL-1 on leukemias and CD3 on T cells, exhibits superior T cell activation and tumour lysing activity. Treatment outcomes of bispecific antibody rely on acute myeloid leukemia cell replication and antibody induced tumour lysing, but their quantitative relationship was unknown. Mathematical models are employed to quantitatively investigate HL-60 cell kinetics determined by bispecific antibody and tumour burden. First, we analysed cytotoxicity assay data testing HL-60 cell against bispecific antibody and T cells, and found efficiency of bispecific antibody induced tumour lysing increases but saturates with increase of HL-60 cell, T cell and bispecific antibody concentration. As a result, their interaction leads to bistable HL-60 cell kinetics; namely, at a given bispecific antibody and T cell concentration interval, HL-60 cell kinetics with small tumour burdens are inhibited but refractory to large tumour burdens. T cell concentration is strong negatively correlated with HL-60 cell concentration. With bispecific antibody clearance, observed bistable HL-60 cell kinetics still exists. Our finding explains observed phenomenon that bispecific antibody was less efficacious at high tumour burden even with enough activated cytotoxic CD8 + T cells. Maintaining high antibody concentration and preventing T-cell exhaustion are equivalently important to sustain long-term control., (© 2024. The Author(s).)

Chronic hepatitis B (CHB) leads to liver inflammation and dysfunction, resulting in liver fibrosis and cancer. Nucleos(t)ide analogues (NAs), inhibitors of hepatitis B virus (HBV), specifically suppress HBV replication. We proposed that immune modulation benefits seroconversion by HBsAg loss. However, activation of T lymphocytes also deteriorates hepatic inflammation. Therefore, we intended to investigate the T cell status and its relationship with hepatic functions in CHB patients treated with NAs. Serum markers, including liver function markers AST, ALT, and HBV-infected markers HBV DNA, HBsAg, HBeAg, and HBsAb were measured in the clinical routine. The T cell levels and markers, including CD69, CD107a, CXCR3, and PD-1 were investigated using flow cytometry. Meanwhile, IFNγ, IL-2, and CXCL10 as immune activation markers in the PBMCs were investigated using qPCR. To validate the effects of NAs on T cell status, qPCR and flow cytometry were used to investigate the gene expression in the HepG2 and PLC5 cells treated with NAs, and in the healthy PBMCs treated with the cell-cultured supernatant. We found that NAs significantly suppressed HBV DNA and reduced AST and ALT levels in the CHB patients. Meanwhile, AST and ALT were both positively correlated with activation marker CD107a in CD8 + T cells. In addition, we found that the CHB patients with seroconversion exhibited a higher CD4/CD8 ratio (p < 0.05) compared to non-seroconversion. We demonstrated that NAs potentially induced IFNs and PD-L1 expression in HepG2 and PLC5 cells. Moreover, the collected supernatant from NAs-treated HepG2 significantly activated PBMCs. This study revealed that the reduction of HBV by NAs may be the reason leading to less AST and ALT levels. We further demonstrated that NAs induced IFN expression in hepatic cells to potentially activate T lymphocytes, which was positively associated with AST and ALT levels in the CHB patients. The results may explain the phenomena in clinical that when the virus is reactivated by aborted use of NAs, it causes consequent T cells-mediated severe acute-on-chronic liver injury., (© 2024. The Author(s).)

Opioid addiction presents a relevant health challenge, with chronic heroin use linked to detrimental effects on various aspects of physical, mental, and sociological health. Opioid maintenance therapy (OMT), particularly using methadone, is the primary treatment option for heroin addiction. Previous studies using blood samples from current heroin addicts and OMT patients have shown immunomodulatory effects of heroin and methadone on T cell function. However, various additional factors beyond heroin and methadone affect these results, including the consumption of other substances, a stressful lifestyle, comorbid psychological and somatic disorders, as well as additional medications. Therefore, we here investigated the direct effects of heroin and methadone on purified human T cells in vitro. Our results reveal that both, heroin and methadone directly suppress Tcell activation and proliferation. Strikingly, this inhibitory effect was markedly stronger in the presence of methadone, correlating with a decrease in secretion of pro-inflammatory cytokines. While heroin did not interfere with the in vitro differentiation and expansion of regulatory Tcells (Tregs), methadone significantly impaired the proliferation of Tregs. Overall, our findings suggest a direct inhibitory impact of both opioids on effector T cell function in vitro, with methadone additionally interfering with Treg induction and expansion in contrast to heroin., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

T cell surface CTLA4 sequesters the costimulatory ligands CD80 and CD86 on antigen-presenting cells (APCs) to prevent autoimmunity. Therapeutic immunosuppression by recombinant CTLA4-immunoglobulin (Ig) fusion proteins, including abatacept, is also attributed to CD80/CD86 blockade. Recent studies show that CTLA4-Ig binding to APC surface cis-CD80:PD-L1 complexes can release the inhibitory ligand PD-L1, but whether this contributes to T cell inhibition remains unclear. Here, we show that PD-L1 liberation by CTLA4-Ig is strictly limited, both in extent and context, relative to PD-L1-competing anti-CD80 antibodies. At APC surface CD80:PD-L1 ratios exceeding 2:1, CTLA4-Ig therapies fail to release PD-L1 regardless of their CD80 affinity. Additionally, introducing flexibility into CTLA4-Ig by modifying its rigid homodimer interface produces biologics that retain bivalent CD80 binding without dissociating cis-bound PD-L1. These findings demonstrate that CTLA4-Ig therapies liberate PD-L1 through a CD80 reorientation mechanism that imposes a strict context dependence to their PD-1 checkpoint agonism and resultant T cell inhibition., Competing Interests: Declaration of interests E.P.O., N.J.K., K.J.G., M.M.G., and R.A.D. are inventors on International Patent Application PCT/AU2022/051296 (filed October 28, 2022) related to this work. E.P.O., N.J.K., and R.A.D. are co-founders of FLEX Immunotherapeutics. N.D.H. is CSO of oNKo-Innate Pty Ltd and declares ownership and funding not related to this work., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Introduction: The serine/threonine kinase 17B (STK17B) is involved in setting the threshold for T cell activation and its absence sensitizes T cells to suboptimal stimuli. Consequently, STK17B represents an attractive potential target for cancer immunotherapy., Methods: To assess the potential of STK17B as an immuno-oncology target, we developed potent and selective tool compounds from starting points in Blueprint Medicines Corporation's proprietary kinase inhibitor library. To characterize these molecules, enzyme and cellular assays for STK17A and STK17B were established to drive chemistry optimization. Mass spectrometry-based phosphoproteomics profiling with tool inhibitors led to the identification of Ser19 on myosin light chain 2 as STK17B substrate, which is then developed into a flow cytometry-based pharmacodynamic readout of STK17B inhibition both in vitro and in vivo ., Results: In a mouse T cell activation assay, STK17B inhibitors demonstrated the ability to enhance interleukin-2 (IL-2) production. Similarly, treatment with STK17B inhibitors resulted in stronger cytokine secretion in human T cells activated using a T cell bispecific antibody. Subsequent chemistry optimization led to the identification of a highly selective and orally bioavailable tool compound, BLU7482. In vivo , STK17B inhibition led to dose-dependent modulation of myosin light chain 2 phosphorylation and enhanced priming of naïve T cells, as determined by upregulation of CD69, IL-2 and interferon-γ secretion. In line with increased T cell activation, treatment with STK17B inhibitor enhanced antitumor activity of anti-PD-L1 antibody in the MCA205 model., Conclusions: In summary, we successfully identified and optimized STK17B kinase inhibitors which led to increased T cell responses in vitro and in vivo . This allowed us to evaluate the potential of STK17B inhibition as an approach for cancer immunotherapy., Competing Interests: Authors FS, JEC, RC, CDS, JG, JLK, CK, KM, RM, EP, YT, TT, RW, RW, and MD were employed by the company Blueprint Medicines Corporation at the time of the study. FS, JG, RC, JK, CK, KM, EP, YT, RM, TT, and RW hold stocks and shares in Blueprint Medicines Corporation. Authors FR, JE, HF, LG, PJ, AM, UH, ST, MT, and JRB were employed by the company F. Hoffmann-La Roche Ltd. at the time of the study. FR and JRB hold stocks in F. Hoffmann-La Roche Ltd. JEC is currently affiliated with Reverie Labs, Cambridge, MA, USA. CDS is currently affiliated with Curie.Bio, Boston, MA, USA. NP is currently affiliated with ROME therapeutics, Boston, MA, USA. ST is currently affiliated with Altos Labs, Los Altos, CA, USA. RW is currently an independent consultant. MD is currently affiliated with Atavistik Bio, Cambridge, MA, USA. The authors declare that this research received funding from Blueprint Medicines Corporation and F. Hoffmann-La Roche Ltd. The sponsor was involved in the study design, collection, analysis, and interpretation of data, as well as data checking of information provided in the manuscript., (Copyright © 2024 Scheuplein, Renner, Campbell, Campbell, De Savi, Eckmann, Fischer, Ge, Green, Jakob, Kim, Kinkema, McGinn, Medina, Müller, Perez, Perola, Timsit, Traore, Hopfer, Tyanova, Tzouros, Wang, Woessner, Dorsch and Bischoff.)

Background: Adoptive cell cancer therapies aim to re-engineer a patient's immune cells to mount an anti-cancer response. Chimeric antigen receptor T and natural killer cells have been engineered and proved successful in treating some cancers; however, the genetic methods for engineering are laborious, expensive, and inefficient and can cause severe toxicities when they over-proliferate., Results: We examined whether the cell-killing capacity of activated T and NK cells could be targeted to cancer cells by anchoring antibodies to their cell surface. Using metabolic glycoengineering to introduce azide moieties to the cellular surface, we covalently attached a dibenzocyclooctyne-modified antibody using the strain-promoted alkyne azide cycloaddition reaction, creating antibody-conjugated T and NK cells. We targeted the immune cells to tumors possessing the xenoantigen, N-glycolyl neuraminic acid GM3 ganglioside, using the 14F7hT antibody. These activated T and NK cells are "armed" with tumour-homing capabilities that specifically lyses antigen-positive cancer cells without off-target toxicities. Moreover, when exposed to target cells, 14F7hT-conjugated T cells that are not preactivated exhibit increased perforin, granzyme, CD69, and CD25 expression and specific cell killing., Conclusions: This research shows the potential for a non-genetic method for redirecting cytotoxic immune cells as a feasible and effective approach for tumor-targeted cell immunotherapy., (© 2024. The Author(s).)

B cells play a key role in humoral immune responses by producing antibodies. Although there are numerous research on memory B cells definition markers and cytokines on B cell development, different studies have yielded contradictory conclusions due to species studied, the different cells and stimulating agents used. In the current study, we conducted a detailed characterization of B cells in human CBMCs, PBMCs and tonsil, including expression of Igs, activation and memory markers. Furthermore, we found that considerable amounts of IgA and IgG were expressed by CD27 - B cells. These "Atypical" memory B cells corresponded to approximately 50% of IgG + and IgA + B cells in blood, this proportion even reached 90% in tonsil. In addition, we investigated the effect of IL-21 and TGF-β1 on the membrane-bound form and secreted form of Igs using PBMCs and purified blood B cells. There were actual differences between the effect of cytokines on Igs secretion and surface expression. Our study will be helpful to advance the knowledge and understanding of humoral memory., (© 2024. The Author(s).)

Dendritic cells (DCs) within the tumor microenvironment (TME) have an insufficient capacity to activate T cells through antigen presentation. Furthermore, the programmed cell-death ligand 1 (PD-L1), abundantly expressed on tumor-associated DCs, binds the programmed cell-death 1 (PD-1)-positive T cells and suppresses their immune function. The binding of PD-L1 to CD80 (B7.1) on the same DC via cis -interactions further prevents T cell costimulation through CD28. Here, we present a strategy to simultaneously promote antigen cross-presentation and block the inhibitory interactions of PD-L1 on DCs to amplify T cell-mediated antitumor responses within the TME. Mesoporous silica nanoparticles (MSNPs) were loaded with clotrimazole (CLT) to boost MHC II-mediated antigen presentation by DCs, surface-modified with mannose to target CD206 on DCs, and then decorated with PD-L1 binding peptide (PDL1bp) to block PD-L1-mediated interactions. PDL1bp was cleaved from the mannosylated and CLT-loaded MSNPs (MSNP-MaN/CLT) under conditions simulating the TME and tethered to PD-L1 to reverse CD80 sequestration on DC2.4 cells. The blocking of PD-L1 by PDL1bp-decorated NPs (MSNP-MaN-PDL1bp) increased the cellular interactions between DC2.4 and EL4 T cells and the amount of IL-2 secretion. The MSNP-MaN/CLT were taken up rapidly by DC2.4 cells, promoted MHC II presentation of hen egg lysozyme (HEL), and increased IL-2 production from HEL antigen-primed 3A9 T cells, which was further enhanced by PDL1bp. In vivo investigation revealed that administration of the CLT-loaded and PDL1bp-functionalized MSNPs remarkably inhibited subcutaneous B16-F10 melanoma tumor growth when compared with anti-PD-L1 therapy. MSNP-MaN-PDL1bp/CLT treatment upregulated the levels of effector molecules such as granzyme B and proinflammatory cytokines (IFNγ and INFα) in the tumor tissue, indicating antitumoral T cell responses. This strategy of utilizing nanoparticles to trigger DC activation while promoting T cell stimulation can be used to amplify the antitumor T cell responses and represents a promising alternative to anti-PD-L1 immunotherapy.

Phosphoantigens (pAgs) induce conformational changes after binding to the intracellular region of BTN3A1 which result in its clustering with BTN2A1, forming an activating ligand for the Vγ9Vδ2 T cell receptor. Here, we designed a small panel of bulky analogs of the prototypical pAg (E)-4-hydroxy-3-methyl-but-2-enyl diphosphate (HMBPP) that contain an aromatic ring attached to the C-3 position in place of methyl group. These compounds bind with high affinity to BTN3A1 but fail to fully support its interaction with BTN2A1 and only partially trigger T cell activation relative to HMBPP. Furthermore, they can compete with HMBPP for cellular binding to BTN3A1 and reduce the cellular response to HMBPP, a classic partial agonist phenotype. Trifluoromethyl analog 6e was the weakest agonist but the strongest inhibitor of HMBPP ELISA response. Our study provides a rationale for the mode of action of pAg-induced γδ T cell activation and provides insights into other naturally occurring BTN proteins and their respective ligands., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Andrew Wiemer reports financial support was provided by National Institutes of Health. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Degenerative joint disease osteoarthritis (OA) is characterized by the degeneration of cartilage, synovial inflammation and low-grade systemic inflammation in association with microbial dysbiosis and intestinal barrier defects. Butyrate is known for its anti-inflammatory and barrier protective effects and might benefit OA patients. In a double-blind placebo-controlled randomized trial, the effects of four to five weeks of oral treatment with sustained-release (SR) butyrate tablets (600 mg/day) on systemic inflammation and immune function were studied in hand OA patients. Serum markers for systemic inflammation and lipopolysaccharide (LPS) leakage were measured and ex vivo stimulation of whole blood or peripheral blood mononuclear cells (PBMCs) was performed at baseline and after treatment. Butyrate treatment did not affect the serum markers nor the cytokine release of ex vivo LPS-stimulated whole blood or PBMCs nor the phenotype of restimulated monocytes. By contrast, butyrate treatment reduced the percentage of activated T helper (Th) cells and the Th17/Treg ratio in αCD3/CD28-activated PBMCs, though cytokine release upon stimulation remained unaffected. Nevertheless, the percentage of CD4+IL9+ cells was reduced by butyrate as compared to the placebo. In both groups, the frequency of Th1, Treg, Th17, activated Th17, CD4+IFNγ+ and CD4+TNFα+ cells was reduced. This study shows a proof of principle of some immunomodulatory effects using a SR butyrate treatment in hand OA patients. The inflammatory phenotype of Th cells was reduced, as indicated by a reduced percentage of Th9 cells, activated Th cells and improved Th17/Treg balance in ex vivo αCD3/CD28-activated PBMCs. Future studies are warranted to further optimize the butyrate dose regime to ameliorate inflammation in OA patients.

Despite recent advances in immunotherapies targeting single tumor-associated antigens, patients with multiple myeloma eventually relapse. ISB 2001 is a CD3 + T cell engager (TCE) co-targeting BCMA and CD38 designed to improve cytotoxicity against multiple myeloma. Targeting of two tumor-associated antigens by a single TCE resulted in superior cytotoxic potency across a variable range of BCMA and CD38 tumor expression profiles mimicking natural tumor heterogeneity, improved resistance to competing soluble factors and exhibited superior cytotoxic potency on patient-derived samples and in mouse models. Despite the broad expression of CD38 across human tissues, ISB 2001 demonstrated a reduced T cell activation profile in the absence of tumor cells when compared to TCEs targeting CD38 only. To determine an optimal first-in-human dose for the ongoing clinical trial ( NCT05862012 ), we developed an innovative quantitative systems pharmacology model leveraging preclinical data, using a minimum pharmacologically active dose approach, therefore reducing patient exposure to subefficacious doses of therapies., (© 2024. The Author(s).)

During the progression of metabolic dysfunction-associated steatohepatitis (MASH), the accumulation of auto-aggressive CD8 + T cells significantly contributes to liver injury and inflammation. Empagliflozin (EMPA), a highly selective inhibitor of sodium-glucose co-transporter 2 (SGLT2), exhibits potential therapeutic benefits for liver steatosis; however, the underlying mechanism remains incompletely elucidated. Here, we found that EMPA significantly reduced the hepatic accumulation of auto-aggressive CD8 + T cells and lowered granzyme B levels in mice with MASH. Mechanistically, EMPA increased β-hydroxybutyric acid by promoting the ketogenesis of CD8 + T cells via elevating 3-hydroxybutyrate dehydrogenase 1 (Bdh1) expression. The β-hydroxybutyric acid subsequently inhibited interferon regulatory factor 4 (Irf4), which is crucial for CD8 + T cell activation. Furthermore, the ablation of Bdh1 in T cells aggravated the manifestation of MASH and hindered the therapeutic efficacy of EMPA. Moreover, a case-control study also showed that SGLT2 inhibitor treatment repressed CD8 + T cell infiltration and improved liver injury in patients with MASH. In summary, our study indicates that SGLT2 inhibitors can target CD8 + T cells and may be an effective strategy for treating MASH., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Aims: Phytocannabinoids and terpenes from Cannabis sativa have demonstrated limited anti-inflammatory and analgesic effects in several inflammatory conditions. In the current study, we test the hypothesis that phytocannabinoids exert immunomodulatory effects in vitro by decreasing inflammatory cytokine expression and activation., Key Methods: CD3/CD28 and lipopolysaccharide activated peripheral blood mononuclear cells (PBMCs) from healthy donors (n = 6) were treated with phytocannabinoid compounds and terpenes in vitro. Flow cytometry was used to determine regulatory T cell (Treg) and T helper 17 (Th17) cell responses to treatments. Cell pellets were harvested for qRT-PCR gene expression analysis of cytokines, cell activation markers, and inflammation-related receptors. Cell culture supernatants were analysed by ELISA to quantify IL-6, TNF-α and IL-10 secretion., Main Findings: In an initial screen of 20 μM cannabinoids and terpenes which were coded to blind investigators, cannabigerol (GL4a), caryophyllene oxide (GL5a) and gamma-terpinene (GL6a) significantly reduced cytotoxicity and gene expression levels of IL6, IL10, TNF, TRPV1, CNR1, HTR1A, FOXP3, RORC and NFKΒ1. Tetrahydrocannabinol (GL7a) suppression of T cell activation was associated with downregulation of RORC and NFKΒ1 gene expression and reduced IL-6 (p < 0.0001) and IL10 (p < 0.01) secretion. Cannabidiol (GL1b) significantly suppressed activation of Tregs (p < 0.05) and Th17 cells (p < 0.05) in a follow-on in vitro dose-response study. IL-6 (p < 0.01) and IL-10 (p < 0.01) secretion was significantly reduced with 50 μM cannabidiol., Significance: The study provides the first evidence that cannabidiol and tetrahydrocannabinol suppress extracellular expression of both anti- and pro-inflammatory cytokines in an in vitro PBMC model of inflammation., Competing Interests: Declaration of competing interest Author JL was employed by GreenLight Pharmaceuticals Ltd. All authors declare no other competing interests. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Drug causality assessment in severe cutaneous adverse reactions (SCARs) remains challenging. We investigated the usefulness of in-vivo drug patch tests (PT), ex-vivo interferon (IFN)-γ enzyme-linked immunospot (ELISpot) assay, and lymphocyte transformation test (LTT) in 30 SCARs patients within the past 36 months. Drug PT yielded a 20% positivity rate (n = 6), while IFN-γ ELISpot and LTT showed positive rates of 56.67% (n = 17) and 41.38% (n = 12), respectively. Combining the three tests resulted in an overall positive rate of 66.67% (n = 20) of cases. IFN-γ ELISpot offered additional positivity, especially with oxypurinol. Employing a combined diagnostic approach may enhance the chances of obtaining a positive result., (© 2024 Japanese Dermatological Association.)

Background: Cannabidiol (CBD), the major non-psychoactive component of cannabis, exhibits anti-inflammatory properties, but less is known about the immunomodulatory potential of CBD on activated natural killer (NK) cells and/or their targets. Many tumor cells present heat shock protein 70 (Hsp70) on their cell surface in a tumor-specific manner and although a membrane Hsp70 (mHsp70) positive phenotype serves as a target for Hsp70-activated NK cells, a high mHsp70 expression is associated with tumor aggressiveness. This study investigated the immuno-modulatory potential of CBD on NK cells stimulated with TKD Hsp70 peptide and IL-2 (TKD+IL-2) and also on HCT116 p53wt and HCT116 p53-/- colorectal cancer cells exhibiting high and low basal levels of mHsp70 expression., Results: Apart from an increase in the density of NTB-A and a reduced expression of LAMP-1, the expression of all other activatory NK cell receptors including NKp30, NKG2D and CD69 which are significantly up-regulated after stimulation with TKD+IL-2 remained unaffected after a co-treatment with CBD. However, the release of major pro-inflammatory cytokines by NK cells such as interferon-γ (IFN-γ) and the effector molecule granzyme B (GrzB) was significantly reduced upon CBD treatment. With respect to the tumor target cells, CBD significantly reduced the elevated expression of mHsp70 but had no effect on the low basal mHsp70 expression. Expression of other NK cell ligands such as MICA and MICB remained unaffected, and the NK cell ligands ULBP and B7-H6 were not expressed on these target cells. Consistent with the reduced mHsp70 expression, treatment of both effector and target cells with CBD reduced the killing of high mHsp70 expressing tumor cells by TKD+IL-2+CBD pre-treated NK cells but had no effect on the killing of low mHsp70 expressing tumor cells. Concomitantly, CBD treatment reduced the TKD+IL-2 induced increased release of IFN-γ, IL-4, TNF-α and GrzB, but CBD had no effect on the release of IFN-α when NK cells were co-incubated with tumor target cells., Conclusion: Cannabidiol (CBD) may potentially diminish the anti-tumor effectiveness of TKD+IL-2 activated natural killer (NK) cells., Competing Interests: Conflict of Interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

CD99 is a transmembrane protein overexpressed in Acute Myeloid Leukemia (AML), presenting a potential novel therapeutic target. Our group has previously developed anti-CD99-A192 (α-CD99-A192), comprising of single chain variable fragment (scFv) and elastin-like polypeptides (ELPs), and reported promising anti-leukemic activity in AML preclinical models. Treatment with α-CD99-A192 induced apoptosis in AML cell lines and prolonged survival in AML xenograft models. Considering CD99's expression and role in T cell activation, in the current study, we propose that α-CD99-A192 plays a dual function, i.e., targeting leukemic cells and activating T cells. This manuscript reports the effects of α-CD99-A192 on T cells in the context of AML. α-CD99-A192 treatment enhances T cell proliferation and activation and increases the release of pro-inflammatory cytokines along with increased aggregation of T cells, which culminates in heightened cytotoxicity against leukemic cells. Altogether, these findings suggest α-CD99-A192 enhances T cell activation and cytotoxic potential consistent with dual mechanisms of action for α-CD99-A192., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Immune checkpoint blocking (ICB), a tumor treatment based on the mechanism of T-cell activation, has shown high efficacy in clinical trials, but not all patients benefit from it. Immune checkpoint inhibitors (ICIs) do not respond to cold tumors that lack effective T-cell infiltration but respond well to hot tumors with sufficient T-cell infiltration. How to convert an unresponsive cold tumor into a responsive hot tumor is an important topic in cancer immunotherapy. Ferroptosis, a newly discovered immunogenic cell death (ICD) form, has great potential in cancer therapy. In the process of deeply understanding the mechanism of cold tumor formation, it was found that ferroptosis showed a powerful immune-activating effect by improving T-cell infiltration, and the combination of ICB therapy significantly enhanced the anti-tumor efficacy. This paper reviews the complex relationship between T cells and ferroptosis, as well as summarizes the various mechanisms by which ferroptosis enhances T cell infiltration: reactivation of T cells and reversal of immunosuppressive tumor microenvironment (TME), as well as recent advances of ICI in combination with targeted ferroptosis therapies, which provides guidance for better improving the ICB efficacy of cold tumors., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Background: Immunological rejection is the most common reason for corneal transplantation failure. The importance of T cells in corneal allograft rejection is well demonstrated. Recent studies highlight that pigment epithelium-derived factor (PEDF) plays an immunoregulatory role in ocular diseases by enhancing the suppressive phenotype of regulatory T cells besides its other functions in neurotrophy and antiangiogenesis., Methods: The effects of PEDF on immune rejection were examined in rat models of corneal transplantation using slit-lamp microscope observation, immunohistochemistry, flow cytometry, and Western blot. In vitro, we demonstrated PEDF reduced alloreactive T-cell activation using real-time polymerase chain reaction, flow cytometry, and Western blot., Results: Topical administration of PEDF provided corneal transplantation rats with an improved graft survival rate of corneal allografts, reduced hemangiogenesis, and infiltration of immune cells in corneas, in particular, type 17 T helper cells while increased regulatory T cells. Moreover, nerve reinnervation within grafts was promoted in PEDF-treated recipient rats. In vitro, PEDF inhibited alloreactive T-cell activation via the c-Jun N-terminal kinase/c-Jun signaling pathway and upregulated the expressions of interleukin-10 and transforming growth factor-β, emphasizing the suppressive role of PEDF on immune responses., Conclusions: Our results underscore the feasibility of PEDF in alleviating corneal allograft rejection and further illustrate its potential in managing immune-related diseases., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Exportin-1 (XPO1/CRM1) plays a central role in the nuclear-to-cytoplasmic transport of hundreds of proteins and contributes to other cellular processes, such as centrosome duplication. Small molecules targeting XPO1 induce cytotoxicity, and selinexor was approved by the Food and Drug Administration in 2019 as a cancer chemotherapy for relapsed multiple myeloma. Here, we describe a cell-type-dependent chromatin-binding function for XPO1 that is essential for the chromatin occupancy of NFAT transcription factors and thus the appropriate activation of T cells. Additionally, we establish a class of XPO1-targeting small molecules capable of disrupting the chromatin binding of XPO1 without perturbing nuclear export or inducing cytotoxicity. This work defines a broad transcription regulatory role for XPO1 that is essential for T cell activation as well as a new class of XPO1 modulators to enable therapeutic targeting of XPO1 beyond oncology including in T cell-driven autoimmune disorders., (© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.)

The potential antitumor function of polysaccharides is well accepted, it is unclear whether polysaccharides have immunoregulatory effect on CD8 + T lymphocyte cells to attack tumor cells. To evaluate the CD8 + T function enhancing role of polysaccharide compounds, the MC38-N4/OT-I co-culture system was established. The synergistic and complementary immune effect of α-glucopyranose-rich compound polysaccharides can be achieved by manipulating the antigen-specific T-cell expansion capacity and efficacy. This study was designed to investigate the antitumor-enhancement activity of a α-glucopyranose-rich compound polysaccharides by determining the activation of CD8 + T cells in a co-culture system. Compared to the control group (42.5 % ± 0.72 %), the specific α-glucopyranose-rich compound polysaccharides, comprising Agaricus blazei Murill, Grifola frondosa and Pericarpium Citri Reticulatae, demonstrated a significant decrease (20.4 % ± 1.23 %, p < 0.05) in the survival rate of MC38-N4 cells in the co-culture system. Additionally, the α-glucopyranose-rich compound polysaccharides resulted in a substantial increase (p < 0.01) in the proportion of CD8 + T cells and CD62L + central memory T cells, which is a less differentiated T cell subset with high immune activity. Collectively, we reported that specific polysaccharide combination, which remodel the function of cytotoxic T cells and provided a basis for improving immune functions by using the specific types of polysaccharides., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Persons with myeloma were randomized to receive an anti-TIGIT (T cell immunoreceptor) or anti-LAG3 (lymphocyte activation gene) antibody followed by combination with pomalidomide and dexamethasone ( NCT04150965 ). Primary and secondary endpoints were safety and efficacy, respectively. Therapy was well tolerated without dose-limiting toxicity. Durable clinical responses were observed in both the anti-TIGIT(three of six participants) and the anti-LAG3 (two of six participants) arms. Anti-LAG3 responders had higher naive cluster of differentiation 4 (CD4)-positive T cells and lower programmed cell death protein 1-positive effector T cells. Anti-TIGIT responders had higher CD226 expression, natural killer cell activation and lower CD112 expression. These data demonstrate the clinical activity of TIGIT-LAG3 blockade and identify pathway-specific response correlates in myeloma., (© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Myeloproliferative neoplasms represent a group of clonal hematopoietic disorders of which myelofibrosis (MF) is the most aggressive. In the context of myeloid neoplasms, there is a growing recognition of the dysregulation of immune response and T-cell function as significant contributors to disease progression and immune evasion. We investigated cytotoxic T-cell exhaustion in MF to restore immune response against malignant cells. Increased expression of inhibitory receptors like CTLA-4 was observed on cytotoxic T cells from MF patients together with a reduced secretion of IFNɣ and TNFɑ. CTLA-4 ligands CD80 and CD86 were increased on MF granulocytes and monocytes highlighting a possible role for myeloid cells in suppressing T-cell activation in MF patients. Unlike healthy donors, the activation of cytotoxic T cells from MF patients was attenuated in the presence of myeloid cells and restored when T cells were cultured alone or treated with anti-CTLA-4. Moreover, anti-CTLA-4 treatment promoted elimination of neoplastic monocytes and granulocytes in a co-culture system with cytotoxic T cells. To test CTLA-4 inhibition in vivo, patient-derived xenografts were generated by transplanting MF CD34+ cells and by infusing homologous T cells in NSGS mice. CTLA-4 blockade reduced human myeloid chimerism and led to T-cell expansion in spleen and bone marrow. Overall, these findings shed light on T-cell dysfunction in MF and suggest that CTLA-4 blockade can boost the cytotoxic T cell-mediated immune response against tumor cells., (© 2024 The Author(s). American Journal of Hematology published by Wiley Periodicals LLC.)

Controlled-release systems enhance anti-tumor effects by leveraging local antigen persistence for antigen-presenting cells (APCs) recruitment and T cell engagement. However, constant antigen presentation alone tends to induce dysfunction in tumor-specific CD8 + T cells, neglecting the synergistic effects of co-stimulatory signal. To address this, we developed a soft particle-stabilized emulsion (SPE) to deliver lipopeptides with controlled release profiles by adjusting their hydrophobic chain lengths: C 6 -SPE (fast release), C 10 -SPE (medium release), and C 16 -SPE (slow release). Following administration, C 6 -SPE release antigen rapidly, inducing early antigen presentation, whereas C 16 -SPE's slow-release delays antigen presentation. Both scenarios missed the critical window for coordinating with the expression of CD86, leading to either T cell apoptosis or suboptimal activation. In contrast, C 10 -SPE achieved a spatiotemporally synergetic effect of the MHC-I-peptide complex and co-stimulatory signal (CD86), leading to effective dendritic cell (DC) activation, enhanced T cell activation, and tumor regression in EG7-OVA bearing mice. Additionally, co-delivery of cytosine-phosphate-guanine (CpG) with SPE provided a sustained expression of the CD86 window for DC activation, improving the immune response and producing robust anti-tumor effects with C 6 -SPE comparable to C 10 -SPE. These findings highlight that synchronizing the spatiotemporal dynamics of antigen presentation and APC activation may confer an optimal strategy for enhanced vaccinations., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024. Published by Elsevier B.V.)

2-deoxy-D-glucose (2DG) is a glycolysis and protein N-glycosylation inhibitor with promising anti-tumor and immunomodulatory effects. However, 2DG can also suppress T cell function, including IFN-γ secretion. Few human T cell studies have studied low-dose 2DG, which can increase IFN-γ in a Jurkat clone. We therefore investigated 2DG's effect on IFN-γ in activated human T cells from PBMCs, with 2DG treatment commenced either concurrently with activation or 48 h after activation. Concurrent 2DG treatment decreased IFN-γ secretion in a dose-dependent manner. However, 2DG treatment of pre-activated T cells had a hormetic effect on IFN-γ, with 0.15-0.6 mM 2DG (achievable in vivo) increasing and >2.4 mM 2DG reducing its secretion. In contrast, IL-2 levels declined monotonously with increasing 2DG concentration. Lower 2DG concentrations reduced PD-1 and increased CD69 expression regardless of treatment timing. The absence of increased T-bet or Eomes expression or IFNG transcription suggests another downstream mechanism. 2DG dose-dependently induced the unfolded protein response, suggesting a possible role in increased IFN-γ secretion, possibly by increasing the ER folding capacity for IFN-γ via increased chaperone expression. Overall, low-dose, short-term 2DG exposure could potentially improve the T cell anti-tumor response., Competing Interests: The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

B-cell lymphoma, clinically, comprises a heterogeneous group of malignancies that encompass various subtypes. CD20 is an optimal target for therapeutic antibodies in B-cell lymphoma immunotherapy since approximately 90% of B-cell malignancies typically exhibit CD20 expression on their surface, while its presence is limited in normal tissues. In this study, we have developed a series of novel non-IgG-like T cell-dependent bispecific antibodies by constructing Fab-FabCH3, referred to as Tandem Antigen-binding Fragment 002 (TFAB002), which specifically target CD20 for the treatment of malignant B-cell lymphoma. TFAB002s display strong binding affinity with CD20 and moderate binding affinity with CD3, thereby triggering target-specific T-cell activation, cytokine release, and tumor cell lysis in vitro. Furthermore, TFAB002s exhibit potent cytotoxicity against B-cell malignancies that express varying levels of CD20. Besides, the TFAB002s show potent pharmacodynamic activity in vivo in the WIL2-S cells CDX mouse model. Collectively, these results underscore the potential of TFAB002s as a highly promising therapeutic approach for selectively depleting CD20-positive B cells, thereby warranting further clinical evaluation as a viable treatment option for CD20-expressing B-cell malignancies., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Li et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Natural killer (NK) cells offer profound advantages against tumor recurrence due to their unique immunological behavior. NK cell therapies associated with the antibody-dependent cell-mediated cytotoxicity (ADCC) effect have made remarkable progress while being limited by insufficient antibody binding and the exhausted state of NK cells in the postsurgical immunosuppressive microenvironment. Leveraging the adherence of PLT to tumor cells, we developed an exogenously implanted platelet (PLT)-based NK cell-driven system (PLT-IgG-IL15) to improve the identifiability of residual tumors with IgG antibody labeling for NK cells catching and engaging, which consequently restored the ADCC effect and promoted the recovery of their killing function. Furthermore, interleukin-15 (IL-15) participated in the augmentation of NK cell function. Collectively, PLT-IgG-IL15 served as an NK cell tumor cell engager as well as an NK cell charger, achieving a <40% recurrence rate in mouse tumor models.

Background: Pemphigus vulgaris (PV) is characterized by autoantibodies targeting keratinocyte adhesion proteins desmoglein (Dsg) 1 and 3, and by the human leukocyte antigen (HLA) predisposition allele HLA-DRB1*0402. Treatment using rituximab (RTX) combined with short-term corticosteroids (CS) allows disease control and long-lasting remission., Objectives: The principal aim of this study was to evaluate the impact of RTX on the circulating subpopulations of Dsg3-specific T lymphocytes that specifically regulate B-cell responses: follicular helper T (Tfh) and follicular regulatory T (Tfr) lymphocytes., Methods: Using the HLA-DRB1*0402 tetramer loaded with the Dsg3 immunodominant peptide, we used flow cytometry to analyse the frequency, polarization and activation status of blood Dsg3-specific follicular T-cell populations at baseline, month (M) 6 and long-term follow-up (M60-90) from patients with PV., Results: At baseline, we observed a predominance of Tfh1* and Tfh17 subsets and an underrepresentation of the Tfh2 subset among autoreactive Dsg3-specific Tfh cells compared with nonautoreactive Tfh cells. RTX treatment induced a decrease of autoreactive Tfh cells with no effect on their polarization during follow-up. In parallel, we observed the emergence of a Dsg3-specific Tfr subpopulation with a significant overexpression of the surface activation markers PD1, ICOS and CD25 that was not observed at the surface of autoreactive Tfh and nonautoreactive Tfr cells of the same patients with PV. In contrast, very few Dsg3-specific Tfr cells were observed in patients with PV who were treated with CS alone., Conclusions: Here we show that the emergence of circulating autoreactive Dsg3-specific Tfr cells is associated with the long-term efficacy of RTX in patients with PV., Competing Interests: Conflicts of interest V.H. reports administrative support was provided by the French Society for Dermatology and Pathology of Sexually Transmitted Diseases. P.J. reports a relationship with Roche SAS that includes board membership. N.F. reports financial support provided by the European Regional Development Fund, the French Society for Dermatology and Pathology of Sexually Transmitted Diseases, the National Institute of Health and Medical Research, the Agence Nationale de la Recherche (ANR) and the Occitanie Region., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Association of Dermatologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Introduction: α-galactosylceramide (α-GalCer), a prototypical agonist of invariant natural killer T (iNKT) cells, stimulates iNKT cells to produce various cytokines such as IFNγ and IL4. Moreover, repeated α-GalCer treatment can cause protective or pathogenic outcomes in various immune-mediated diseases. However, the precise role of α-GalCer-activated iNKT cells in sepsis development remains unclear. To address this issue, we employed a lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced murine sepsis model and two alternative models., Methods: Sepsis was induced in wild-type (WT) C57BL/6 (B6) mice by three methods (LPS/D-GalN, α-GalCer/D-GalN, and cecal slurry), and these mice were monitored for survival rates. WT B6 mice were intraperitoneally injected with α-GalCer or OCH (an IL4-biased α-GalCer analog) one week prior to the induction of sepsis. To investigate the effects of α-GalCer-mediated iNKT cell activation on sepsis development, immune responses were analyzed by flow cytometry using splenocytes and liver-infiltrating leukocytes. In addition, a STAT6 inhibitor (AS1517499) and an IL10 inhibitor (AS101) were employed to evaluate the involvement of IL4 or IL10 signaling. Furthermore, we performed B cell adoptive transfers to examine the contribution of α-GalCer-induced regulatory B (Breg) cell populations in sepsis protection., Results: In vivo α-GalCer pretreatment polarized iNKT cells towards IL4- and IL10-producing phenotypes, significantly attenuating LPS/D-GalN-induced septic lethality in WT B6 mice. Furthermore, α-GalCer pretreatment reduced the infiltration of immune cells to the liver and attenuated pro-inflammatory cytokine production. Treatment with a STAT6 inhibitor was unable to modulate disease progression, indicating that IL4 signaling did not significantly affect iNKT cell-mediated protection against sepsis. This finding was confirmed by pretreatment with OCH, which did not alter sepsis outcomes. However, interestingly, prophylactic effects of α-GalCer on sepsis were significantly suppressed by treatment with an IL10 antagonist, suggesting induction of IL10-dependent anti-inflammatory responses. In addition to IL10-producing iNKT cells, IL10-producing B cell populations were significantly increased after α-GalCer pretreatment., Conclusion: Overall, our results identify α-GalCer-mediated induction of IL10 by iNKT and B cells as a promising option for controlling the pathogenesis of postoperative sepsis., Competing Interests: LVK is a scientific advisory board member of Isu Abxis Co., Ltd. Republic of Korea. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Park, Lee, Kim, Park, Van Kaer and Hong.)

Allergic asthma is a major health burden on society as a chronic respiratory disease characterized by inflammation and muscle tightening around the airways in response to inhaled allergens. Daphne kiusiana Miquel is a medicinal plant that can suppress allergic airway inflammation; however, its specific molecular mechanisms of action are unclear. In this study, we aimed to elucidate the mechanisms by which D. kiusiana inhibits allergic airway inflammation. We evaluated the anti-inflammatory effects of the ethyl acetate (EA) fraction of D. kiusiana and its major compound, daphnetin, on murine T lymphocyte EL4 cells stimulated with phorbol 12-myristate 13-acetate and ionomycin in vitro and on asthmatic mice stimulated with ovalbumin in vivo. The EA fraction and daphnetin inhibited T-helper type 2 (Th2) cytokine secretion, serum immunoglobulin E production, mucus secretion, and inflammatory cell recruitment in vivo. In vitro, daphnetin suppressed intracellular Ca 2+ mobilization (a critical regulator of nuclear factor of activated T cells) and functions of the activator protein 1 transcription factor to reduce interleukin (IL)-4 and IL-13 expression. Daphnetin effectively suppressed the IL-4/-13-induced activation of Janus kinase (JAK)/signal transducer and activator of transcription 6 (STAT6) signaling in vitro and in vivo, thereby inhibiting the expression of GATA3 and PDEF, two STAT6-target genes responsible for producing Th2 cytokines and mucins. These findings indicate that daphnetin suppresses allergic airway inflammation by stabilizing intracellular Ca 2+ levels and subsequently inactivating the JAK/STAT6/GATA3/PDEF pathway, suggesting that daphnetin is a promising alternative to existing asthma treatments., Competing Interests: Declaration of competing interest None: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

CD137 (4-1BB) costimulation results in the potent activation of antitumor T lymphocytes and elicits antitumor efficacy that is synergistic with anti-PD(L)1 checkpoint inhibitors, especially when using bispecific constructs. Emerging experimental evidence indicates that 4-1BB ligation prevents and may revert T-cell exhaustion. See related article by Jeon et al., p. 4155., (©2024 American Association for Cancer Research.)

Luteolin, a commonly used traditional Chinese medicine, has been utilized for several decades in the treatment of hepatocellular carcinoma (HCC). Previous research has demonstrated its anti-tumour efficacy, but its underlying mechanism remains unclear. This study aimed to assess the therapeutic effects of luteolin in H22 tumour-bearing mice. luteolin effectively inhibited the growth of solid tumours in a well-established mouse model of HCC. High-throughput sequencing revealed that luteolin treatment could enhance T-cell activation, cell chemotaxis and cytokine production. In addition, luteolin helped sustain a high ratio of CD8 + T lymphocytes in the spleen, peripheral blood and tumour tissues. The effects of luteolin on the phenotypic and functional changes in tumour-infiltrating CD8 + T lymphocytes were also investigated. Luteolin restored the cytotoxicity of tumour-infiltrating CD8 + T lymphocytes in H22 tumour-bearing mice. The CD8 + T lymphocytes exhibited intensified phenotype activation and increased production of granzyme B, IFN-γ and TNF-α in serum. The combined administration of luteolin and the PD-1 inhibitor enhanced the anti-tumour effects in H22 tumour-bearing mice. Luteolin could exert an anti-tumour immune response by inducing CD8 + T lymphocyte infiltration and enhance the anti-tumour effects of the PD-1 inhibitor on H22 tumour-bearing mice., (© 2024 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Unsaturated fatty acids (UFA) are crucial for T-cell effector functions, as they can affect the growth, differentiation, survival, and function of T cells. Nonetheless, the mechanisms by which UFA affects T-cell behavior are ill-defined. Therefore, we analyzed the processing of oleic acid, a prominent UFA abundantly present in blood, adipocytes, and the fat pads surrounding lymph nodes, in CD4 + T cells. We found that exogenous oleic acid increases proliferation and enhances the calcium flux response upon CD3/CD28 activation. By using a variety of techniques, we found that the incorporation of oleic acid into membrane lipids, rather than regulation of cellular metabolism or TCR expression, is essential for its effects on CD4 + T cells. These results provide novel insights into the mechanism through which exogenous oleic acid enhances CD4 + T-cell function., (© 2024 The Author(s). European Journal of Immunology published by Wiley‐VCH GmbH.)

CpG ODN2006 is widely used as a potent B cell stimulant in vitro and in vivo. However, it shows a deficit in targeting naïve B cells in vitro. In this study, we investigated whether α-IgM can support ODN2006-induced effects on B cells to obtain enhanced activation with focus on different B cell subsets. Our results delineated robust B cell activation, shown by increased activation marker expression and cytokine secretion by each agent alone, and further augmented when used in combination. Interestingly, α-IgM targeted mainly naïve and marginal zone-like B cells, thus complementing the pronounced effects of ODN2006 on memory B cells and achieving optimal activation for all B cell subsets. Taken together, combining ODN2006 and α-IgM is beneficial for in vitro activation including all B cell subsets. Furthermore, our results suggest that α-IgM could enhance efficacy of ODN2006 in vivo with further need of investigation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

For adoptive therapy with T cell receptor engineered T (TCR-T) cells, the quantity and quality of the final cell product directly affect their anti-tumor efficacy. The post-transfer efficacy window of TCR-T cells is keen to optimizing attempts during the manufacturing process. Cbl-b is a E3 ubiquitin ligase previously shown with critical negative impact in T cell functions. This study investigated whether strategic inclusion of a commercially available small inhibitor targeting Cbl-b (Cbl-b-IN-1) prior to T cell activation could enhance the quality of the final TCR-T cell product. Examination with both PBMCs and TCR-T cells revealed that Cbl-b-IN-1 treatment promoted TCR expression efficiency, T cell proliferation potential and, specifically, cell survival capability post antigenic stimulation. Cbl-b-IN-1 exposure facilitated T cells in maintaining less differentiated states with enhanced cytokine production. Further, we found that Cbl-b-IN-1 effectively augmented the activation of TCR signaling, shown by increased phosphorylation levels of Zeta-chain-associated protein kinase 70 (ZAP70) and phospholipase c-γ1 (PLCγ1). In conclusion, our results evidence that the inclusion of Cbl-b inhibitor immediately prior to TCR-T cell activation may enhance their proliferation, survival, and function potentials, presenting an applicable optimization strategy for immunotherapy with adoptive cell transfer., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

A balanced immune system is essential to maintain adequate host defense and effective self-tolerance. While an immune system that fails to generate appropriate response will permit infections to develop, uncontrolled activation may lead to autoinflammatory or autoimmune diseases. To identify drug candidates capable of modulating immune cell functions, we screened 1200 small molecules from the Prestwick Chemical Library for their property to inhibit innate or adaptive immune responses. Our studies focused specifically on drug interactions with T cells, B cells, and polymorphonuclear leukocytes (PMNs). Candidate drugs that were validated in vitro were examined in preclinical models to determine their immunomodulatory impact in chronic inflammatory diseases, here investigated in chronic inflammatory skin diseases. Using this approach, we identified several candidate drugs that were highly effective in preclinical models of chronic inflammatory disease. For example, we found that administration of pyrvinium pamoate, an FDA-approved over-the-counter anthelmintic drug, suppressed B cell activation in vitro and halted the progression of B cell-dependent experimental pemphigoid by reducing numbers of autoantigen-specific B cell responses. In addition, in studies performed in gene-deleted mouse strains provided additional insight into the mechanisms underlying these effects, for example, the receptor-dependent actions of tamoxifen that inhibit immune-complex-mediated activation of PMNs. Collectively, our methods and findings provide a vast resource that can be used to identify drugs that may be repurposed and used to promote or inhibit cellular immune responses., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Cyclosporin A (CSA) and tacrolimus (TAC) suppress T-cell activation and subsequent proliferation by inhibiting calcineurin. Though they have the same target, CSA and TAC have quite different molecular structures, indicating quantitative and/or qualitative differences in their effects., Objective: CD28 is a costimulatory molecule that enhances T-cell activation. It has also been shown to attenuate calcineurin inhibitors. In this study, we compared the CD28-mediated resistance of CD4+ T cells to those calcineurin inhibitors and tried to predict CD28's impact on infectious diseases., Methods: CD4+ T-cell proliferation was induced with anti-CD3 mAb in the presence or absence of anti-CD28 mAb in vitro. CSA or TAC was added at various concentrations, and the half-maximal inhibitory concentration on CD4+ T-cell proliferation was determined. Effects of lipopolysaccharide (LPS) on dendritic cells (DCs) and CD4+ T-cell proliferation were also evaluated in vitro., Results: Anti-CD28 mAb conferred CD4+ T cells with resistance to both CSA and TAC, and CD28's effect on the latter was approximately twice that on the former. LPS induced expression of CD28 ligands CD80/86 on DCs. The addition of LPS to culture containing DCs seemed to make CD4+ T cells slightly resistant to TAC but not to CSA. However, its effect on the former was very weak under our experimental conditions., Conclusions: CD28 attenuated TAC more strongly than CSA. Although LPS did not demonstrate strong enough resistance in our in vitro model, TAC might maintain a better antibacterial immune response than CSA in clinical use.

The challenges generated by insufficient T cell activation and infiltration have constrained the application of immunotherapy. Making matters worse, the complex tumor microenvironment (TME), resistance to apoptosis collectively poses obstacles for cancer treatment. The carrier-free small molecular self-assembly strategy is a current research hotspot to overcome these challenges. This strategy can transform multiple functional agents into sustain-released hydrogel without the addition of any excipients. Herein, a coordination and hydrogen bond mediated tricomponent hydrogel (Cel hydrogel) composed of glycyrrhizic acid (GA), copper ions (Cu 2+ ) and celastrol (Cel) was initially constructed. The hydrogel can regulate TME by chemo-dynamic therapy (CDT), which increases reactive oxygen species (ROS) in conjunction with GA and Cel, synergistically expediting cellular apoptosis. What's more, copper induced cuproptosis also contributes to the anti-tumor effect. In terms of regulating immunity, ROS generated by Cel hydrogel can polarize tumor-associated macrophages (TAMs) into M1-TAMs, Cel can induce T cell proliferation as well as activate DC mediated antigen presentation, which subsequently induce T cell proliferation, elevate T cell infiltration and enhance the specific killing of tumor cells, along with the upregulation of PD-L1 expression. Upon co-administration with aPD-L1, this synergy mitigated both primary and metastasis tumors, showing promising clinical translational value., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)