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Traditional vaccination strategies have failed to generate effective vaccines for many infections like tuberculosis and HIV. New approaches are needed for each type of disease. The protective immunity and distinct responses of many successful vaccines come from activating multiple Toll-like receptors (TLRs). Vaccines with multiple TLRs as adjuvants have proven effective in preclinical studies, but current research has not explored two important elements. First, few multi-TLR systems explore spatial organization-a critical feature of whole-cell vaccines. Second, no multi-TLR systems to date provide systematic analysis of the combinatorial space of three TLR agonists. Here, we present the first examination of the combinatorial space of several spatially defined triple-TLR adjuvants, by synthesizing a series of five triple-TLR agonists and testing their innate activity both in vitro and in vivo. The combinations were evaluated by measuring activation of immune stimulatory genes (Nf-κB, ISGs), cytokine profiles (IL12-p70, TNF-α, IL-6, IL-10, CCL2, IFN-α, IFN-β, IFN-γ), and in vivo cytokine serum levels (IL-6, TNF-α, IL12-p40, IFN-α, IFN-β). We demonstrate that linking TLR agonists substantially alters the resulting immune response compared to their unlinked counterparts and that each combination results in a distinct immune response, particularly between linked combinations. We show that combinations containing a TLR9 agonist produce more Th1 biasing immune response profiles, and that the effect is amplified upon conjugation. However, combinations containing TLR2/6 agonist are skewed toward TH2 biasing profiles despite the presence of TLR9. These results demonstrate the profound effects that conjugation and combinatorial administration of TLR agonists can have on immune responses, a critical element of vaccine development.

Gut lymphocytes and the microbiota establish a reciprocal relationship that impacts the host immune response. Class I-restricted T cell-associated molecule (CRTAM) is a cell adhesion molecule expressed by intraepithelial T cells and is required for their retention in the gut. In this study, we show that CRTAM expression affects gut microbiota composition under homeostatic conditions. Moreover, Crtam-/- mice infected with the intestinal pathogen Salmonella exhibit reduced Th17 responses, lower levels of inflammation, and reduced Salmonella burden, which is accompanied by expansion of other microbial taxa. Thus, CRTAM enhances susceptibility to Salmonella, likely by promoting the inflammatory response that promotes the pathogen's growth. We also found that the gut microbiota from wild-type mice, but not from Crtam-/- mice, induces CRTAM expression and Th17 responses in ex-germ-free mice during Salmonella infection. Our study demonstrates a reciprocal relationship between CRTAM expression and the gut microbiota, which ultimately impacts the host response to enteric pathogens.

CXCL17 is a homeostatic chemokine in the mucosa known to chemoattract dendritic cells and macrophages but can also be expressed elsewhere under inflammatory conditions. Cxcl17-/- mice have lower numbers of macrophages or dendritic cells in mucosal tissues. CXCL17 is also able to chemoattract suppressor myeloid cells that can recruit regulatory T cells. To explore a possible role of Cxcl17 in T cells, we studied T cell populations from Cxcl17-/- or wild-type (WT) littermate mice. Cxcl17-/- mice have higher numbers of CD4+ and CD8+ T cells in spleen and lymph nodes (LNs). Upon activation, they produce higher levels of several proinflammatory cytokines and chemokines. Furthermore, a Cxcl17-/- mouse developed exacerbated disease in a T cell-dependent model of experimental autoimmune encephalomyelitis (EAE). By 18 days after immunization with myelin oligodendrocyte peptide, only 44% of Cxcl17-/- mice were still alive vs. 90% for WT mice. During EAE, Cxcl17-/- mice exhibited higher numbers of lymphoid and myeloid cells in spleen and LNs, whereas they had less myeloid cell infiltration in the CNS. Cxcl17-/- mice also had higher levels of some inflammatory cytokines in serum, suggesting that they may be involved in the poor survival of these mice. Abnormal T cell function may reflect altered myeloid cell migration, or it could be due to altered T cell development in the thymus. We conclude that CXCL17 is a novel factor regulating T cell homeostasis and function.

CCL28 is a mucosal chemokine that has been involved in various responses, including IgA production. We have analyzed its production in human tissues using a comprehensive microarray database. Its highest expression is in the salivary gland, indicating that it is an important component of saliva. It is also expressed in the trachea, bronchus, and in the mammary gland upon onset of lactation. We have also characterized a Ccl28-/- mouse that exhibits very low IgA levels in milk, and the IgA levels in feces are also reduced. These observations confirm a role for the CCL28/CCR10 chemokine axis in the recruitment of IgA plasmablasts to the lactating mammary gland. CCL28 is also expressed in the vomeronasal organ. We also detected olfactory defects (anosmia) in a Ccl28-/- mouse suggesting that CCL28 is involved in the function/development of olfaction. Importantly, Ccl28-/- mice are highly susceptible to Salmonella enterica serovar Typhimurium in an acute model of infection, indicating that CCL28 plays a major role in innate immunity against Salmonella in the gut. Finally, microbiome studies revealed modest differences in the gut microbiota between Ccl28-/- mice and their cohoused wild-type littermates. The latter observation suggests that under homeostatic conditions, CCL28 plays a limited role in shaping the gut microbiome.

We have described a novel cytokine encoded by a gene called Meteorin-like (Metrnl). Metrnl is a small (∼28 kDa) secreted protein expressed by activated macrophages and barrier tissues (mucosa and skin). Metrnl production by bone marrow macrophages is induced by several cytokines including TNF-α, IL-17α, IL-12, and IL-4 and inhibited by IFN-γ and TGF-β. Metrnl expression in macrophages is also induced by LPS, and its levels in circulation are associated with inflammatory responses in vivo. Furthermore, Metrnl regulates the production of several cytokines and chemokines in macrophages. We have produced a Metrnl-/- mouse, which is viable and shows normal development. However, it exhibits dysregulated cytokine production, alterations in IgG production, and is highly susceptible to LPS in a sepsis model. Furthermore, older Metrnl-/- mice develop inflammatory lesions, suggesting that Metrnl participates in the control of inflammatory responses. Taken together, these observations indicate that Metrnl encodes a novel immunoregulatory cytokine associated with inflammatory responses that we have designated Meteorin-β.

BackgroundWound healing represents a dynamic process involving directional migration of different cell types. Chemokines, a family of chemoattractive proteins, have been suggested to be key players in cell-to-cell communication and essential for directed migration of structural cells. Today, the role of the chemokine network in cutaneous wound healing is not fully understood. Unraveling the chemokine-driven communication pathways in this complex process could possibly lead to new therapeutic strategies in wound healing disorders.MethodsWe performed a systematic, comprehensive time-course analysis of the expression and function of a broad variety of cytokines, growth factors, adhesion molecules, matrixmetalloproteinases and chemokines in a murine cutaneous wound healing model.ResultsStrikingly, chemokines were found to be among the most highly regulated genes and their expression was found to coincide with the expression of their matching receptors. Accordingly, we could show that resting and activated human primary keratinocytes (CCR3, CCR4, CCR6, CXCR1, CXCR3), dermal fibroblasts (CCR3, CCR4, CCR10) and dermal microvascular endothelial cells (CCR3, CCR4, CCR6, CCR8, CCR9, CCR10, CXCR1, CXCR2, CXCR3) express a distinct and functionally active repertoire of chemokine receptors. Furthermore, chemokine ligand-receptor interactions markedly improved the wound repair of structural skin cells in vitro.ConclusionTaken together, we here present the most comprehensive analysis of mediators critically involved in acute cutaneous wound healing. Our findings suggest therapeutic approaches for the management of wound closure by targeting the chemokine network.

Cytokines are important molecules that regulate the ontogeny and function of the immune system. They are small secreted proteins usually produced upon activation of cells of the immune system, including lymphocytes and myeloid cells. Many cytokines have been described, and several have been recognized as pivotal players in immune responses and in human disease. In fact, several anticytokine antibodies have proven effective therapeutics, especially in various autoimmune diseases. In the last 15 years, new cytokines have been described, and many remain poorly understood. Among the most recent cytokines discovered are interleukins-30 (IL-30) to IL-40. Several of these are members of other cytokine superfamilies, including several IL-1 superfamily members (IL-33, IL-36, IL-37, and IL-38) as well as several new members of the IL-12 family (IL-30, IL-35, and IL-39). The rest (IL-31, IL-32, IL-34, and IL-40) are encoded by genes that do not belong to any cytokine superfamily. Our aim of this review was to present a concise version of the information available on these novel cytokines to facilitate their understanding by members of the immunological community.

Patients undergoing abdominal oncologic surgical procedures require particular surgical and anesthesiologic considerations. Traditional pain management, such as opiate treatment, continuous epidural analgesia, and non-opioid drugs, may have serious side effects in this patient population. We evaluated erector spinae plane (ESP) blocks for postoperative pain management following elective oncologic abdominal surgeries. In this single-center, prospective, and randomized study, we recruited 100 patients who underwent elective oncological abdominal surgery between December 2020 and January 2022 at Soroka University Medical Center in Beer Sheva, Israel. We compared postoperative pain levels in patients who were treated with a preincisional ESP block in addition to traditional pain management with intravenous opioids, non-steroidal anti-inflammatory drugs (NSAIDs), and acetaminophen, compared to patients who were only given traditional pain management (control). Patients who were treated with a preincisional ESP block demonstrated significantly lower Visual Analog Scale scores at 60 minutes and 4, 8, and 12 hours following the surgery, compared to the control group (p

Background and objectiveOver the past decade, researchers have been seeking to understand the consequences of adult attention-deficit/hyperactivity disorder (ADHD) for different types of everyday behaviors. In this study, we investigated the associations between ADHD and political participation and attitudes, as ADHD may impede their active participation in the polity.MethodsThis observational study used data from an online panel studying the adult Jewish population in Israel, collected prior the national elections of April 2019 (N = 1369). ADHD symptoms were assessed using the 6-item Adult ADHD Self-Report (ASRS-6). Political participation (traditional and digital), news consumption habits, and attitudinal measures were assessed using structured questionnaires. Multivariate linear regression analyses were conducted to analyze the association between ADHD symptoms (ASRS score Results200 respondents (14.6%) screened positive for ADHD based on the ASRS-6. Our findings show that individuals with ADHD are more likely to participate in politics than individuals without ADHD symptoms (B = 0.303, SE = 0.10, p = .003). However, participants with ADHD are more likely to be passive consumers of news, waiting for current political news to reach them instead of actively searching for it (B = 0.172, SE = 0.60, p = .004). They are also more prone to support the idea of silencing other opinions (B = 0.226, SE = 0.10, p = .029). The findings hold when controlling for age, sex, level of education, income, political orientation, religiosity, and stimulant therapy for ADHD symptoms.ConclusionsOverall, we find evidence that individuals with ADHD display a unique pattern of political activity, including greater participation and less tolerance of others' views, but not necessarily showing greater active interest in politics. Our findings add to a growing body of literature that examines the impact of ADHD on different types of everyday behaviors.

MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) are two relevant classes of non-coding RNAs (ncRNAs) that play a pivotal role in a number of molecular processes through different epigenetic regulatory mechanisms of gene expression. As a matter of fact, the altered expression of these types of RNAs leads to the development and progression of a varied range of multifactorial human diseases. Several recent reports elucidated that miRNA and lncRNAs have been implicated in pancreatic cancer (PC). For instance, dysregulation of such ncRNAs has been found to be associated with chemoresistance, apoptosis, autophagy, cell differentiation, tumor suppression, tumor growth, cancer cell proliferation, migration, and invasion in PC. Moreover, several aberrantly expressed miRNAs and lncRNAs have the potential to be used as biomarkers for accurate PC diagnosis. Additionally, miRNAs and lncRNAs are considered as promising clinical targets for PC. Therefore, in this review, we discuss recent experimental evidence regarding the clinical implications of miRNAs and lncRNAs in the pathophysiology of PC, their future potential, as well as the challenges that have arisen in this field of study in order to drive forward the design of ncRNA-based diagnostics and therapeutics for PC.

IntroductionWe aimed to assess the clinical significance of M1-MCA occlusion with visualization of both MCA-M2 segments [“Tilted-V sign” (TVS)] on initial CT angiography (CTA) in patients with acute ischemic stroke (AIS) undergoing endovascular thrombectomy (EVT).MethodsData for patients with consecutive AIS undergoing EVT for large vessel occlusion (LVO) in two academic centers are recorded in ongoing databases. Patients who underwent EVT for M1-MCA occlusions ≤ 6 h from symptom onset were included in this retrospective analysis.ResultsA total of 346 patients met the inclusion criteria; 189 (55%) had positive TVS. Patients with positive TVS were younger (68 ± 14 vs. 71 ± 14 years, P = 0.028), with similar rates of vascular risk factors and baseline modified Rankin scores (mRS) 0–2. The rates of achieving thrombolysis in cerebral ischemia (TICI) 2b-3 were similar to the two groups (79%), although successful first-pass recanalization was more common with TVS (64 vs. 36%, p = 0.01). On multivariate analysis, higher collateral score [odds ratio (OR) 1.38 per unit increase, p = 0.008] and lower age (OR 0.98 per year increase, p = 0.046) were significant predictors of TVS. Patients with positive TVS had higher post-procedural Alberta Stroke Program Early CT Score (ASPECTS; 6.9 ± 2.2 vs. 5.2 ± 2.3, p = 0.001), were discharged with lower National Institutes of Health Stroke Score (NIHSS; 6±6 vs. 9±7, p = 0.003) and higher rates of mRS 0–2 (29.5 vs. 12%, p = 0.001), and had lower rates of 90-day mortality (13.2 vs. 21.6%, p = 0.038). However, TVS was not an independent predictor of functional independence (OR 2.51; 95% CI 0.7–8.3).ConclusionTilted-V Sign, an easily identifiable radiological marker, is associated with fewer recanalization attempts, better functional outcomes, and reduced mortality.

Michael Semyonov,1,* Ekaterina Fedorina,1,* Anna Shalman,1 Michael Dubilet,1 Yael Refaely,2 Leonid Ruderman,2 Dmitry Frank,1 Benjamin F Gruenbaum,3 Leonid Koyfman,1 Michael Friger,4 Alexander Zlotnik,1 Moti Klein,1 Evgeni Brotfain1 1Department of Anesthesiology and Critical Care, General Intensive Care Unit, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel; 2Department of Cardiothoracic Surgery, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel; 3Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Jacksonville, FL, USA; 4Department of Public Health, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel*These authors contributed equally to this workCorrespondence: Evgeni BrotfainDepartment of Anesthesiology and Critical Care, Soroka Medical Center, Ben Gurion University of the Negev, Beer Sheva, 84101, IsraelTel +972 54-621-8106Email bem1975@gmail.comPurpose: Neuropathic, chronic pain is a common and severe complication following thoracic surgery, known as post-thoracotomy pain syndrome (PTPS). Here we evaluated the efficacy of an ultrasound-guided serratus anterior plane block (SAPB) on pain control compared to traditional pain management with intravenous opioids and nonsteroidal anti-inflammatory drugs (NSAIDs) six months after thoracic surgery.Patients and Methods: In this retrospective observational study, we analyzed data from a questionnaire survey. We interviewed all patients who underwent elective video-assisted thoracoscopy surgery (VATS) at Soroka University Medical Center between December 2016 and January 2018. The responses of ninety-one patients were included.Results: Participants reported PTPS in both groups, 43% of patients in the SAPB group and 57% of patients in the standard group, which failed to reach significance. However, we demonstrated that the percentage of pain occurrence trended lower in the SAPB group. There was significantly less burning/stitching or shooting, shocking, pressure-like, and aching pain in SAPB patients compared to the standard protocol group. Patients in the SAPB group had significantly less pain located in the upper and lower posterior thorax anatomical regions compared to the standard protocol group. Moreover, we found a significant difference in occurrence of PTPS depending on the type of thoracic surgery. From both study groups, 69% of patients who underwent lobectomy reported pain, compared with 41.9% of those in the segmental (wedge resection) procedure, and 42.1% of patients in other procedures.Conclusion: While the present study did not demonstrate a statistically significant reduction of PTPS after SAPB concerning postoperative pain control, there was a trend of a decrease. We also found significance in the type of pain and location of pain after thoracic surgery between the two groups, as well as a significant difference between pain occurrence in types of thoracic surgeries from both groups.Keywords: chronic pain, post-thoracotomy pain syndrome, PTPS, regional anesthesia block, serratus anterior, thoracic surgery

Epilepsy is associated with substantial neuropsychiatric impairments that persist long after the onset of the condition, significantly impacting quality of life. The goal of this review was to uncover how the pathological consequences of epilepsy, such as excessive glutamate release and a disrupted blood–brain barrier (BBB), contribute to the emergence of neuropsychiatric disorders. We hypothesize that epilepsy induces a dysfunctional BBB through hyperexcitation, which then further amplifies post-ictal glutamate levels and, thus, triggers neurodegenerative and neuropsychiatric processes. This review identifies the determinants of glutamate concentration levels in the brain and explores potential therapeutic interventions that restore BBB integrity. Our focus on therapeutic BBB restoration is guided by the premise that it may improve glutamate regulation, consequently mitigating the neurotoxicity that contributes to the onset of neuropsychiatric symptoms. [ABSTRACT FROM AUTHOR]

Postpartum hemorrhage (PPH) remains a major cause of maternal mortality. Tranexamic acid (TxA) has shown effectiveness in reducing PPH-related maternal bleeding events and deaths. We conducted a cohort study including parturient women at high risk of bleeding after undergoing a cesarean section (CS). Participants were divided into two groups: the treatment group received prophylactic 1-g TxA before surgery (n = 500), while the comparison group underwent CS without TxA treatment (n = 500). The primary outcome measured increased maternal blood loss following CS, defined as more than a 10% drop in hemoglobin concentration within 24 h post-CS and/or a drop of ≥2 g/dL in maternal hemoglobin concentration. Secondary outcomes included PPH indicators, ICU admission, hospital stay, TxA complications, and neonatal data. TxA administration significantly reduced hemoglobin decrease by more than 10%: there was a 35.4% decrease in the TxA group vs. a 59.4% decrease in the non-TxA group, p < 0.0001 and hemoglobin decreased by ≥2 g/dL (11.4% in the TxA group vs. 25.2% in non-TxA group, p < 0.0001), reduced packed red blood cell transfusion (p = 0.0174), and resulted in lower ICU admission rates (p = 0.034) and shorter hospitalization (p < 0.0001). Complication rates and neonatal outcomes did not differ significantly. In conclusion, prophylactic TxA administration during high-risk CS may effectively reduce blood loss, providing a potential intervention to improve maternal outcomes.

Glass fiber-reinforced polymer (GFRP) of high performance, as a relatively ideal partial or complete substitute for steel, could increase the possibility of adapting structures to changes in harsh weather environments. While GFRP is combined with concrete in the form of bars, the mechanical characteristics of GFRP cause the bonding behavior to differ significantly from that of steel-reinforced members. In this paper, a central pull-out test was applied, according to ACI440.3R-04, to analyze the influence of the deformation characteristics of GFRP bars on bonding failure. The bond–slip curves of the GFRP bars with different deformation coefficients exhibited distinct four-stage processes. Increasing the deformation coefficient of the GFRP bars is able to significantly improve the bond strength between the GFRP bars and the concrete. However, while both the deformation coefficient and concrete strength of the GFRP bars were increased, the bond failure mode of the composite member was more likely to be changed from ductile to brittle. The results show members with larger deformation coefficients and moderate concrete grades, which generally have excellent mechanical and engineering properties. By comparing with the existing bond and slip constitutive models, it was found that the proposed curve prediction model was able to well match the engineering performance of GFRP bars with different deformation coefficients. Meanwhile, due to its high practicality, a four-fold model characterizing representative stress for the bond–slip behavior was recommended in order to predict the performance of the GFRP bars.

Circulating conventional memory CD8+ T cells (i.e., the CD8+ effector memory T [TEM] cell and CD8+ central memory T [TCM] cell subsets) and the noncirculating CD8+ tissue-resident memory T (TRM) cell subset play a critical role in mucosal immunity. Mucosal chemokines, including the recently discovered CXCL17, are also important in mucosal immunity because they are homeostatically expressed in mucosal tissues. However, whether the CXCL17 chemokine contributes to the mobilization of memory CD8+ T cell subsets to access infected mucosal tissues remains to be elucidated. In this study, we report that after intravaginal HSV type 1 infection of B6 mice, we detected high expression levels of CXCL17 and increased numbers of CD44highCD62LlowCD8+ TEM and CD103highCD8+ TRM cells expressing CXCR8, the cognate receptor of CXCL17, in the vaginal mucosa (VM) of mice with reduced genital herpes infection and disease. In contrast to wild-type B6 mice, the CXCL17-/- mice developed 1) fewer CXCR8+CD8+ TEM and TRM cells associated with more virus replication in the VM and more latency established in dorsal root ganglia, and 2) reduced numbers and frequencies of functional CD8+ T cells in the VM. These findings suggest that the CXCL17/CXCR8 chemokine pathway plays a crucial role in mucosal vaginal immunity by promoting the mobilization of functional protective CD8+ TEM and CD8+ TRM cells, within this site of acute and recurrent herpes infection.

We consider compact finite-difference schemes of the 4th approximation order for an initial-boundary value problem (IBVP) for the n-dimensional nonhomogeneous wave equation, n≥ 1. Their construction is accomplished by both the classical Numerov approach and alternative technique based on averaging of the equation, together with further necessary improvements of the arising scheme for n≥ 2. The alternative technique is applicable to other types of PDEs including parabolic and time-dependent Schrödinger ones. The schemes are implicit and three-point in each spatial direction and time and include a scheme with a splitting operator for n≥ 2. For n = 1 and the mesh on characteristics, the 4th order scheme becomes explicit and close to an exact four-point scheme. We present a conditional stability theorem covering the cases of stability in strong and weak energy norms with respect to both initial functions and free term in the equation. Its corollary ensures the 4th order error bound in the case of smooth solutions to the IBVP. The main schemes are generalized for non-uniform rectangular meshes. We also give results of numerical experiments showing the sensitive dependence of the error orders in three norms on the weak smoothness order of the initial functions and free term and essential advantages over the 2nd approximation order schemes in the non-smooth case as well.

Parkinson’s disease (PD) is taking a staggering toll on healthcare systems worldwide, with the bulk of the expenditures invested in the late stages of the disease. Considering the rising life expectancy and the increasing prevalence of PD across the globe, a clear understanding of the early signs and treatment options available for advanced PD (APD), will facilitate tailoring management programs and support services. This task is complicated by the lack of both global consensus in defining APD and standardized care guidelines. This perspective prepared by a panel of movement disorder specialists, proposes to extend and optimize currently accepted PD coding to better reflect the diverse disease manifestations, with emphasis on non-motor features. The panel seeks to promote timely diagnosis by adjustment of evaluation tools for use by community neurologists and suggests modification of eligibility criteria for advanced therapy. Moreover, it advocates multidisciplinary assessments of APD patients to drive personalized, patient-centered and holistic management. Overall, earlier and more targeted intervention is expected to markedly improve patient quality of life.

In the field of bone regeneration, insertion of scaffolds favours bone formation by triggering the differentiation of mesenchymal cells into osteoblasts. The presence of Calcium ions (Ca2+) in the interstitial fluid across scaffolds is thought to play a relevant role in the process. In particular, the Ca2+ patterns can be used as an indicator of where to expect bone formation. In this work, we analyse the inverse problem for these distribution patterns, using an advection-diffusion nonlinear model for the concentration of Ca2+. That is, given a set of observables which are related to the amount of expected bone formation, we aim at determining the values of the parameters that best fit the data. The problem is solved in a realistic 3D-printed structured scaffold for two uncertain parameters: the amplitude of the velocity of the interstitial fluid and the ionic release rate from the scaffold. The minimization in the inverse problem requires multiple evaluations of the nonlinear model. The computational cost is alleviated by the combination of standard Proper Orthogonal Decomposition (POD), to reduce the number of degrees of freedom, with an adhoc hyper-reduction strategy, which avoids the assembly of a full-order system at every iteration of the Newton’s method. The proposed hyper-reduction method is formulated using the Principal Component Analysis (PCA) decomposition of suitable training sets, devised from the weak form of the problem. In the numerical tests, the hyper-reduced formulation leads to accurate results with a significant reduction of the computational demands with respect to standard POD.

Despite the remarkable successes of cancer immunotherapies, the majority of patients will experience only partial response followed by relapse of resistant tumors. While treatment resistance has frequently been attributed to clonal selection and immunoediting, comparisons of paired primary and relapsed tumors in melanoma and breast cancers indicate that they share the majority of clones. Here, we demonstrate in both mouse models and clinical human samples that tumor cells evade immunotherapy by generating unique transient cell-in-cell structures, which are resistant to killing by T cells and chemotherapies. While the outer cells in this cell-in-cell formation are often killed by reactive T cells, the inner cells remain intact and disseminate into single tumor cells once T cells are no longer present. This formation is mediated predominantly by IFNγ-activated T cells, which subsequently induce phosphorylation of the transcription factors signal transducer and activator of transcription 3 (STAT3) and early growth response-1 (EGR-1) in tumor cells. Indeed, inhibiting these factors prior to immunotherapy significantly improves its therapeutic efficacy. Overall, this work highlights a currently insurmountable limitation of immunotherapy and reveals a previously unknown resistance mechanism which enables tumor cells to survive immune-mediated killing without altering their immunogenicity.

We describe a novel B cell-associated cytokine, encoded by an uncharacterized gene (C17orf99; chromosome 17 open reading frame 99), that is expressed in bone marrow and fetal liver and whose expression is also induced in peripheral B cells upon activation. C17orf99 is only present in mammalian genomes, and it encodes a small (∼27-kDa) secreted protein unrelated to other cytokine families, suggesting a function in mammalian immune responses. Accordingly, C17orf99 expression is induced in the mammary gland upon the onset of lactation, and a C17orf99-/- mouse exhibits reduced levels of IgA in the serum, gut, feces, and lactating mammary gland. C17orf99-/- mice have smaller and fewer Peyer's patches and lower numbers of IgA-secreting cells. The microbiome of C17orf99-/- mice exhibits altered composition, likely a consequence of the reduced levels of IgA in the gut. Although naive B cells can express C17orf99 upon activation, their production increases following culture with various cytokines, including IL-4 and TGF-β1, suggesting that differentiation can result in the expansion of C17orf99-producing B cells during some immune responses. Taken together, these observations indicate that C17orf99 encodes a novel B cell-associated cytokine, which we have called IL-40, that plays an important role in humoral immune responses and may also play a role in B cell development. Importantly, IL-40 is also expressed by human activated B cells and by several human B cell lymphomas. The latter observations suggest that it may play a role in the pathogenesis of certain human diseases.