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Myeloid cells, including antigen-presenting cells (APCs) and myeloid-derived suppressor cells (MDSCs) play opposing roles to orchestrate innate and adaptive immune responses during physiological and pathological conditions. We investigated the role of DNA methylation in regulating the transcription of inhibitory/suppressive molecules in myeloid suppressive cells (identified as CD33+HLA-DR–) in comparison to APCs. We selected a number of immune checkpoints (ICs), IC ligands, and immunosuppressive molecules that have been implicated in MDSC function, including PD-L1, TIM-3, VISTA, galectin-9, TGF-β, ARG1 and MMP9. We examined their mRNA expression levels, and investigated whether DNA methylation regulates their transcription in sorted myeloid cell subpopulations. We found that mRNA levels of PD-L1, TIM-3, TGF-β, ARG1 and MMP9 in CD33+HLA-DR– cells were higher than APCs. However, VISTA and galectin-9 mRNA levels were relatively similar in both myeloid subpopulations. CpG islands in the promoter regions of TGF-β1, TIM-3 and ARG1 were highly unmethylated in CD33+HLA-DR–cells, compared with APCs, suggesting that DNA methylation is one of the key mechanisms, which regulate their expression. However, we did not find differences in the methylation status of PD-L1 and MMP9 between CD33+HLA-DR– and APCs, suggesting that their transcription could be regulated via other genetic and epigenetic mechanisms. The promoter methylation status of VISTA was relatively similar in both myeloid subpopulations. This study provides novel insights into the epigenetic mechanisms, which control the expression of inhibitory/suppressive molecules in circulating CD33+HLA-DR– cells in a steady-state condition, possibly to maintain immune tolerance and haemostasis.

With a broad range of hosts, Salmonella enterica serovar Typhimurium (S. Typhimurium) is the major cause of gastroenteritis in human beings and systemic disease in susceptible mice strains. However, different S. Typhimurium strains differ in regard to virulence and host adaptation. Here, C57BL/6 mice were infected, respectively, with different S. Typhimurium strains SL1344 (calf), CVCC541 (chicken) and CMCC50115 (mutton) to determine their virulence and host immune responses. It was found that mice were less susceptible to infection by S. Typhimurium CVCC541 and CMCC50115 strains, with lower lethality and decreased bacterial burden in liver and spleen. Besides, S. Typhimurium strains CVCC541 and CMCC50115 enhanced host innate immune responses by increased frequencies of macrophages and neutrophils 3 days after infection. But SL1344 strain evaded immune response by inducing apoptosis of macrophages. Moreover, CVCC541 could elicit adaptive immune responses of host 11 days after infection upon examination of the proliferation and activation of CD4+ T cells. In addition, 125 and 138 unique mutant coding genes, respectively, in S. Typhimurium strains CVCC541 and CMCC50115 and 78 shared mutant coding genes were annotated by genomic alignment to SL1344 genome and the signal pathways involving these genes were further analyzed. The acquired results indicate that different original S. Typhimurium strains show differential virulence and may induce diverse immune responses in the same host infected.

As a means of obtaining reproducible and accurate numbers of larvae for laboratory rearing, we tested a large-particle flow-cytometer type device called the ‘Automated Particle Counter’ (APC). The APC is a gravity-fed, self-contained unit that detects changes in light intensity caused by larvae passing the detector in a water stream and controls dispensing by stopping the flow when the desired number has been reached. We determined the accuracy (number dispensed compared to the target value) and precision (distribution of number dispensed) of dispensing at a variety of counting sensitivity thresholds and larva throughput rates (larvae per second) using < 1-day old Anopheles gambiae and Aedes aegypti larvae. All measures were made using an APC algorithm called the ‘Smoothed Z-Score’ which allows the user to define how many standard deviations (Z scores) from the baseline light intensity a particle’s absorbance must exceed to register a count. We dispensed a target number of 100 An. gambiae larvae using Z scores from 2.5–8 and observed no difference among them in the numbers dispensed for scores from 2.5–6, however, scores of 7 and 8 under-counted (over-dispensed) larvae. Using a Z score ≤ 6, we determined the effect of throughput rate on the accuracy of the device to dispense An. gambiae larvae. For rates ≤ 98 larvae per second, the accuracy of dispensing a target of 100 larvae was - 2.29% ± 0.72 (95% CI of the mean) with a mode of 99 (49 of 348 samples). When using a Z score of 3.5 and rates ≤ 100 larvae per second, the accuracy of dispensing a target of 100 Ae. aegypti was - 2.43% ± 1.26 (95% CI of the mean) with a mode of 100 (6 of 42 samples). No effect on survival was observed on the number of An. gambiae first stage larvae that reached adulthood as a function of dispensing.

Immunotherapy has shown tremendous promise for improving cancer treatment. Unfortunately, antigen‐presenting cells (APCs) in cancer patients cannot effectively recognize and process tumor antigens to activate host immune responses. In this study, an approach is developed to improve cancer immunotherapy that utilizes endogenous antigen‐carrying nanoparticles (EAC‐NPs), which encompasses a set of antigens isolated from solid tumors and adjuvants. The EAC‐NPs specifically target APCs and subsequently result in enhanced T cell responses and improved antitumor efficacy. Mechanistic studies reveal that the EAC‐NPs enhance and prolong the presence of immune compounds in APCs, which ensure persistent antigen loading and stimulation, induce a rapid proliferation of CD4+ and CD8+ T cells, and significantly increase the ratios of intratumoral CD4+ T/Treg and CD8+ T/Treg. The work using nanotechnology provides a promising strategy in improving antitumor immunity by enhancing the immunogenicity and presentation of tumor self‐antigens for cancer immunotherapy., Endogenous antigen‐carrying nanoparticles are phagocytosed by antigen‐presenting cells (APCs) triggering antigen and Toll‐like receptor signaling. Then the APCs induce highly efficient differentiation of T cells toward helper T (CD4+) cells and cytotoxic T lymphocytes (CD8+) to finally generate potent antitumor immune responses. A promising strategy is established for cancer immunotherapy by enhancing the immunogenicity and presentation of tumor self‐antigens.

Purpose To develop a new intradermal antigen delivery system by coating microneedle arrays with lipid bilayer-coated, antigen-loaded mesoporous silica nanoparticles (LB-MSN-OVA). Methods Synthesis of MSNs with 10-nm pores was performed and the nanoparticles were loaded with the model antigen ovalbumin (OVA), and coated with a lipid bilayer (LB-MSN-OVA). The uptake of LB-MSN-OVA by bone marrow-derived dendritic cells (BDMCs) was studied by flow cytometry. The designed LB-MSN-OVA were coated onto pH-sensitive pyridine-modified microneedle arrays and the delivery of LB-MSN-OVA into ex vivo human skin was studied. Results The synthesized MSNs demonstrated efficient loading of OVA with a maximum loading capacity of about 34% and the lipid bilayer enhanced the colloidal stability of the MSNs. Uptake of OVA loaded in LB-MSN-OVA by BMDCs was higher than that of free OVA, suggesting effective targeting of LB-MSN-OVA to antigen-presenting cells. Microneedles were readily coated with LB-MSN-OVA at pH 5.8, yielding 1.5 μg of encapsulated OVA per microneedle array. Finally, as a result of the pyridine modification, LB-MSN-OVA were effectively released from the microneedles upon piercing the skin. Conclusion Microneedle arrays coated with LB-MSN-OVA were successfully developed and shown to be suitable for intradermal delivery of the encapsulated protein antigen. Electronic supplementary material The online version of this article (doi:10.1007/s11095-017-2177-4) contains supplementary material, which is available to authorized users.

// Garima Garg 1 , Eirini Nikolouli 1 , Matthias Hardtke-Wolenski 2 , Aras Toker 1 , Naganari Ohkura 3,4 , Michael Beckstette 1 , Takahisa Miyao 5 , Robert Geffers 6 , Stefan Floess 1 , Norbert Gerdes 7,8 , Esther Lutgens 7,9 , Anke Osterloh 10 , Shohei Hori 5 , Shimon Sakaguchi 3,4 , Elmar Jaeckel 2 and Jochen Huehn 1 1 Department of Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany 2 Department of Gastroenterology, Hepatology, Endocrinology, Hannover Medical School, Hannover, Germany 3 Department of Experimental Immunology, World Premier International Immunology Frontier Research Center, Osaka University, Suita, Japan 4 Department of Experimental Pathology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan 5 Laboratory for Immune Homeostasis, RIKEN Center for Integrative Medical Sciences, Yokohama City, Kanagawa, Japan 6 Genome Analytics, Helmholtz Centre for Infection Research, Braunschweig, Germany 7 Institute for Cardiovascular Prevention, Ludwig-Maximilians-University, Munich, Germany 8 Division of Cardiology, Pulmonology, and Vascular Medicine Medical Faculty, University Hospital Dusseldorf, Dusseldorf, Germany 9 Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, AZ, Amsterdam, The Netherlands 10 Department of Immunology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany Correspondence to: Jochen Huehn, email: // Keywords : regulatory T cells, thymic APCs, epigenetic modification, alloantigen-specificity, Immunology and Microbiology Section, Immune response, Immunity Received : October 15, 2016 Accepted : March 03, 2017 Published : March 15, 2017 Abstract Regulatory T cells (Tregs) are potential immunotherapeutic candidates to induce transplantation tolerance. However, stability of Tregs still remains contentious and may potentially restrict their clinical use. Recent work suggested that epigenetic imprinting of Foxp3 and other Treg-specific signature genes is crucial for stabilization of immunosuppressive properties of Foxp3 + Tregs, and that these events are initiated already during early stages of thymic Treg development. However, the mechanisms governing this process remain largely unknown. Here we demonstrate that thymic antigen-presenting cells (APCs), including thymic dendritic cells (t-DCs) and medullary thymic epithelial cells (mTECs), can induce a more pronounced demethylation of Foxp3 and other Treg-specific epigenetic signature genes in developing Tregs when compared to splenic DCs (sp-DCs). Transcriptomic profiling of APCs revealed differential expression of secreted factors and costimulatory molecules, however neither addition of conditioned media nor interference with costimulatory signals affected Foxp3 induction by thymic APCs in vitro . Importantly, when tested in vivo both mTEC- and t-DC-generated alloantigen-specific Tregs displayed significantly higher efficacy in prolonging skin allograft acceptance when compared to Tregs generated by sp-DCs. Our results draw attention to unique properties of thymic APCs in initiating commitment towards stable and functional Tregs, a finding that could be highly beneficial in clinical immunotherapy.

// Zhang Yiwen 1, 2, 3, * , Gao Shilin 1, 2, 3, * , Chen Yingshi 1, 2, 3 , Su Lishi 1, 2, 3 , Luo Baohong 1, 2, 3 , Liu Chao 1, 2, 3 , Li Linghua 4 , Pan Ting 1, 2, 3 , Zhang Hui 1, 2, 3 1 Institute of Human Virology, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China 2 Key Laboratory of Tropical Disease Control of Ministry of Education, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China 3 Guangdong Engineering Research Center for Antimicrobial Agent and Immunotechnology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, 510080, China 4 Department of Infectious Diseases, Guangzhou 8th People’s Hospital, Guangzhou, Guangdong, 510080, China * These authors have contributed equally to this work Correspondence to: Zhang Hui, email: zhangh92@mail.sysu.edu.cn Pan Ting, email: pant8@mail.sysu.edu.cn Keywords: B-lymphocytes, APC, BAFF, HIV-immunotherapy, tumor Received: April 07, 2016 Accepted: October 14, 2016 Published: October 21, 2016 ABSTRACT Efficient antigen presentation is indispensable for cytotoxic T lymphocyte (CTL)-mediated immunotherapy. B-lymphocytes propagated with CD40L have been developed as antigen-presenting cells (APCs), but this capacity needs further optimization. Here, we aimed to expand human B-lymphocytes on a large scale while maintaining their antigen-presenting ability by using both CD40L and B-cell activating factor (BAFF). The addition of BAFF enhanced the expansion efficiency and prolonged the culture time without causing apoptosis of the expanded B-cells. This method thus provided an almost unlimited source of cellular adjuvant to achieve sufficient expansion of CTLs in cases where several rounds of stimulation are required. We also showed that the addition of BAFF significantly enhanced the expression of major costimulatory molecules, CD80 and CD86. Subsequently, the antigen-presenting ability of the B-lymphocytes also increased. Consequently, these B-lymphocytes showed robust CTL responses to inhibit tumor growth after tumor-specific peptide pulses. A similar method induced potent antigen-specific CTL responses, which effectively eradicated human immunodeficiency virus type 1 (HIV-1) latency in CD4 T-lymphocytes isolated from patients receiving suppressive anti-retroviral therapy (ART). Together, our findings indicate that potent antigen-specific CTLs can be generated using BAFF-activated B-lymphocytes as APCs ex vivo. This approach can be applied for CTL-mediated immunotherapy in patients with cancers or chronic viral infections.

// Viswa Teja Colluru 1,2 and Douglas G. McNeel 1,2 1 Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA 2 Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI, USA Correspondence to: Douglas G. McNeel, email: // Keywords : DNA vaccine, B cells, dendritic cells, direct presentation, Immunology and Microbiology Section, Immune response, Immunity Received : July 26, 2016 Accepted : September 16, 2016 Published : September 21, 2016 Abstract In spite of remarkable preclinical efficacy, DNA vaccination has demonstrated low immunogenicity in humans. While efforts have focused on increasing cross-presentation of DNA-encoded antigens, efforts to increase DNA vaccine immunogenicity by targeting direct presentation have remained mostly unexplored. In these studies, we compared the ability of different APCs to present antigen to T cells after simple co-culture with plasmid DNA. We found that human primary peripheral B lymphocytes, and not monocytes or in vitro derived dendritic cells (DCs), were able to efficiently encode antigen mRNA and expand cognate tumor antigen-specific CD8 T cells ex vivo . Similarly, murine B lymphocytes co-cultured with plasmid DNA, and not DCs, were able to prime antigen-specific T cells in vivo. Moreover, B lymphocyte-mediated presentation of plasmid antigen led to greater Th1-biased immunity and was sufficient to elicit an anti-tumor effect in vivo . Surprisingly, increasing plasmid presentation by B cells, and not cross presentation of peptides by DCs, further augmented traditional plasmid vaccination. Together, these data suggest that targeting plasmid DNA to B lymphocytes, for example through transfer of ex vivo plasmidloaded B cells, may be novel means to achieve greater T cell immunity from DNA vaccines.

// Hong Zheng 1, * , Xin Liu 1, * , Jianhong Zhang 1 , Shawn J. Rice 1 , Matthias Wagman 1 , Yaxian Kong 2 , Liuluan Zhu 2 , Junjia Zhu 1 , Monika Joshi 1 , Chandra P. Belani 1 1 Penn State Hershey Cancer Institute, Penn State College of Medicine, Hershey, PA, USA 2 Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing Key Laboratory of Emerging Infectious Diseases, Beijing, China * These authors have contributed equally to this work Correspondence to: Chandra Belani, e-mail: cbelani@psu.edu Keywords: PD-1, peripheral blood, T cells, prognosis, NSCLC Received: February 12, 2016 Accepted: April 13, 2016 Published: May 12, 2016 ABSTRACT Recent success of using agents inhibiting the major immune check point, programmed cell death-1 (PD-1) pathway, offers a great promise for effective cancer therapy. Two blocking antibodies for PD-1, nivolumab and pembrolizumab have recently been approved for treating advanced recurrent non-small cell lung cancer (NSCLC). Activation of PD-1 on T cells and PD-L1 on tumor cells or antigen presenting cells leads to T cell exhaustion and ultimately tumor growth. In this study, we performed flow cytometry analysis of peripheral blood samples collected from patients with advanced NSCLC at initial diagnosis. We report that surface expression of PD-1 on CD4 + T cells has a prognostic value in NSCLC patients, as high expression of PD-1 is associated with a shorter progression-free survival and overall survival. Importantly, we also found that high PD-1 expression on peripheral CD4 + T cells is associated with inferior clinical response in a subset of patients who received anti-PD-L1 treatment, indicating a potential predictive value of this marker. This work highlights the potential of a non-invasive and effective method to determine prognostic and predictive biomarkers for inhibiting the PD-1 pathway in NSCLC patients.

// Longhao Sun 1 , Hao Guo 1 , Ruoyu Jiang 1 , Li Lu 1 , Tong Liu 1 , Zhixiang Zhang 1 and Xianghui He 1 1 Department of General Surgery, Tianjin Medical University General Hospital, Tianjin, China Correspondence to: Xianghui He, email: // Keywords : artificial antigen-presenting cells, alpha-fetoprotein, interleukin-15, cytotoxic T lymphocytes, adoptive immunotherapy, Immunology and Microbiology Section, Immune response, Immunity Received : November 30, 2015 Accepted : March 14, 2016 Published : March 19, 2016 Abstract Professional antigen-presenting cells (APCs) are potent generators of tumor antigen-specific cytotoxic T lymphocytes (CTLs) for adoptive immunotherapy; however, generation of APCs is cumbersome, expensive, and subject to the tumor microenvironment. Artificial APCs (aAPCs) have been developed as a cost-effective alternative to APCs. We developed a cellular aAPC that efficiently generated alpha-fetoprotein (AFP)-specific CTLs. We genetically modified the human B cell lymphoma cell line BJAB with a lentiviral vector to establish an aAPC called BA15. The expression of AFP 158-166 -HLA-A*02:01 complex, CD80, CD86, and interleukin (IL)-15 in BA15 cells was assessed. The efficiency of BA15 at generating AFP-specific CTLs and the specific cytotoxicity of CTLs against AFP+ cells were also determined. BA15 cells expressed high levels of AFP 158-166 peptide, HLA-A2, CD80, CD86, and IL-15. BA15 cells also exhibited higher efficiency in generating AFP-specific CTLs than did dendritic cells. These CTLs had greater cytotoxicity against AFP+ hepatocellular carcinoma cells than did CTLs obtained from dendritic cells in vitro and in vivo . Our novel aAPC system could provide a robust platform for the generation of functional AFP-specific CTLs for adoptive immunotherapy of hepatocellular carcinoma.

Background Memory CD8+ T cell responses play an essential role in protection against persistent infection. However, HIV-1 evades vaccine-induced memory CD8+ T cell response by mechanisms that are not fully understood. Methods We analyzed the temporal dynamics of CD8+ T cell recall activity and function during EcoHIV infection in a potent PD1-based vaccine immunized immunocompetent mice. Findings Upon intraperitoneal EcoHIV infection, high levels of HIV-1 GAG-specific CD8+ T lymphocytes recall response reduced EcoHIV-infected cells significantly. However, this protective effect diminished quickly after seven days, followed by a rapid reduction of GAG-specific CD8+ T cell number and activity, and viral persistence. Mechanistically, EcoHIV activated dendritic cells (DCs) and myeloid cells. Myeloid cells were infected and rapidly expanded, exhibiting elevated PD-L1/-L2 expression and T cell suppressive function before day 7, and were resistant to CD8+ T cell-mediated apoptosis. Depletion of myeloid-derived suppressor cells (MDSCs) reduced EcoHIV infection and boosted T cell responses. Interpretation This study provides an overview of the temporal interplay of persistent virus, DCs, MDSCs and antigen-specific CD8+ T cells during acute infection. We identify MDSCs as critical gatekeepers that restrain antiviral T cell memory responses, and highlight MDSCs as an important target for developing effective vaccines against chronic human infections. Funding Hong Kong Research Grant Council (T11–709/18-N, HKU5/CRF/13G), General Research Fund (17122915 and 17114114), Hong Kong Health and Medical Research Fund (11100752, 14130582, 16150662), Grant RGC-ANR A-HKU709/14, the San-Ming Project of Medicine (SZSM201512029), University Development Fund of the University of Hong Kong and Li Ka Shing Faculty of Medicine Matching Fund to HKU AIDS Institute.

Hepatitis B can be effectively prevented by hepatitis B vaccination. However, hyporesponse to the hepatitis B vaccine has been found in both human and inbred mice with particular MHC alleles or haplotypes, but the mechanisms underlying this poor response remains elusive. In the present study, we investigated the mechanisms underlying the hyporesponse to hepatitis B vaccination using B10.S-H2s/SgMcdJ (B10.S, H-2(s), poor responder) and C57BL/10J (B10, H-2(b), good responder) mice. We observed that the B10.S mice displayed a hyporesponse to HBsAg vaccine but a normal response to 3 other foreign antigens (influenza A (H1N1) 2009 monovalent vaccine, tetanus toxoid and ovalbumin). In B10.S mice immunized with HBsAg, the levels of serum anti-HBs IgG, the number of HBsAg-specific IgG-secreting plasma cells and HBsAg-specific Th cells were considerably lower than that in B10 mice. Further, the findings of the insufficient maturation (CD86), co-stimulation (CD40) and migration (CCR7) activities of DCs together with the inadequate activation of the HBsAg-specific Th cells by APCs were identified as part of the reason for the HBsAg hyporesponse in B10.S mice, which supports the hypothesis that measures aimed at promoting the maturation, co-stimulation or migration of APCs to enhance Th cell activation may be a useful strategy for the development of new hepatitis B vaccines.

When pathogenic stresses are recognized by innate immune cells, inflammasomes are assembled and caspase-1 is activated, resulting in the conversion of pro-IL-18 into mature IL-18. Because natural killer (NK) cells express IL-18 receptors, IL-18 may play roles in immune functions of NK cells. In the present study, we examined the effect of IL-18 on NK cells derived from lung cancer patients and healthy adult volunteers. When peripheral blood NK cells were stimulated with IL-2, the cells formed clusters beginning on day 5-6 and proliferated thereafter, in which the number of NK cells increased by 10-fold in 10 days. When IL-18 was added, cell clusters were observed as early as on day 4 and NK cells proliferated vigorously. On day 10, the expansion rate was 56-fold on average, showing that IL-18 promoted the expansion of NK cells. It was also notable that IL-18 enhanced the expression of CD80, CD86, HLA-DR and HLA-DQ on NK cells, suggesting that IL-18 conferred NK cells an APC-like phenotype. When cellular cytotoxicity was determined, APC-like NK cells efficiently killed tumor cells and anti-tumor activity was augmented by the addition of tumor antigen-specific mAbs. In addition, IFN-γ was produced by APC-like NK cells in response to tumor cells, and the cytokine production was further enhanced by mAbs. Taken together, IL-18 not only promoted the expansion of NK cells, but also changed the phenotype of NK cells. IL-2/IL-18-induced NK cells might, therefore, serve as a bridge between innate immunity and adaptive immunity and be useful for cancer immunotherapy.

We evaluated the impact of premature cell death of antigen-presenting cells (APCs) by Caspase-1- and RipK3-signaling pathways on CD8+ T-cell priming during infection of mice with Salmonella typhimurium (ST). Our results indicate that Caspase1 and RipK3 synergize to rapidly eliminate infected APCs, which does not influence the initial activation of CD8+ T cells. However, the maintenance of primed CD8+ T cells was greatly compromised when both these pathways were disabled. Caspase-1- and RipK3-signaling did not influence NF-κB signaling in APCs, but synergized to promote processing of IL-1 and IL-18. Combined deficiency of Caspase1 and RipK3 resulted in compromised innate immunity and accelerated host fatality due to poor processing of IL-18. In contrast, synergism in cell death by Caspase-1- and RipK3 resulted in restriction of PD-1 and TIM3 expression on primed CD8+ T cells, which promoted the survival of activated CD8+ T cells.

Chronic viral hepatitis B (CHB) is a major global health problem. A therapeutic vaccine for CHB comprised of yeast-derived recombinant HBsAg-anti-HBs immunogenic complexes (YIC) has been devloped by us. A series of clinical trials has shown its therapeutic efficacy in decreasing HBV viral load and converting serum HBeAg-positive to anti-HBe-positive status in a subpopulation of CHB patients. Herein, we present a study of the immuno-potentiating mechanisms of YIC revealed by live-cell imaging technology. We studied internalization and dissociation of YIC in cells in vitro, and antigen presentation and T cell stimulation in mice. We found that after YIC was internalized via the Fcγ receptors (FcγR) of antigen presenting cells, it was subsequently transferred through early and late endosomal into lysosomal compartments. The dissociation of YIC was mainly observed in the late endosome. Furthermore when YIC were injected into mice, the populations of IFN-γ- and TNF-α-producing CD8+ and CD4+ T cells were higher in the YIC group than in controls receiving antigen or antibody alone. These observations supplement the known mechanisms of YIC action as a therapeutic vaccine for CHB.

Cross-presentation is the process by which professional APCs load peptides from an extracellularly derived protein onto class I MHC molecules to trigger a CD8(+) T cell response. The ability to enhance this process is therefore relevant for the development of antitumor and antiviral vaccines. We investigated a new TLR2-based adjuvant, Small Molecule Immune Potentiator (SMIP) 2.1, for its ability to stimulate cross-presentation. Using OVA as model antigen, we demonstrated that a SMIP2.1-adjuvanted vaccine formulation induced a greater CD8(+) T cell response, in terms of proliferation, cytokine production and cytolytic activity, than a non-adjuvanted vaccine. Moreover, using an OVA-expressing tumor model, we showed that the CTLs induced by the SMIP2.1 formulated vaccine inhibits tumor growth in vivo. Using a BCR transgenic mouse model we found that B cells could cross-present the OVA antigen when stimulated with SMIP2.1. We also used a flow cytometry assay to detect activation of human CD8(+) T cells isolated from human PBMCs of cytomegalovirus-seropositive donors. Stimulation with SMIP2.1 increased the capacity of human APCs, pulsed in vitro with the pp65 CMV protein, to activate CMV-specific CD8(+) T cells. Therefore, vaccination with an exogenous antigen formulated with SMIP2.1 is a successful strategy for the induction of a cytotoxic T cell response along with antibody production.

The P140 peptide, a 21-mer linear peptide (sequence 131-151) generated from the spliceosomal SNRNP70/U1-70K protein, contains a phosphoserine residue at position 140. It significantly ameliorates clinical manifestations in autoimmune patients with systemic lupus erythematosus and enhances survival in MRL/lpr lupus-prone mice. Previous studies showed that after P140 treatment, there is an accumulation of autophagy markers sequestosome 1/p62 and MAP1LC3-II in MRL/lpr B cells, consistent with a downregulation of autophagic flux. We now identify chaperone-mediated autophagy (CMA) as a target of P140 and demonstrate that its inhibitory effect on CMA is likely tied to its ability to alter the composition of HSPA8/HSC70 heterocomplexes. As in the case of HSPA8, expression of the limiting CMA component LAMP2A, which is increased in MRL/lpr B cells, is downregulated after P140 treatment. We also show that P140, but not the unphosphorylated peptide, uses the clathrin-dependent endo-lysosomal pathway to enter into MRL/lpr B lymphocytes and accumulates in the lysosomal lumen where it may directly hamper lysosomal HSPA8 chaperoning functions, and also destabilize LAMP2A in lysosomes as a result of its effect on HSP90AA1. This dual effect may interfere with the endogenous autoantigen processing and loading to major histocompatibility complex class II molecules and as a consequence, lead to lower activation of autoreactive T cells. These results shed light on mechanisms by which P140 can modulate lupus disease and exert its tolerogenic activity in patients. The unique selective inhibitory effect of the P140 peptide on CMA may be harnessed in other pathological conditions in which reduction of CMA activity would be desired.

Nosocomial infections represent serious complications after traumatic or surgical injuries in intensive care units. The pathogenesis of the underlying immunosuppression is only incompletely understood. In the present study, we investigated whether injury interferes with the function of the adaptive immune system in particular with the differentiation of antigen-specific T helper (Th)-cell responses in vivo. We used a mouse model for traumatic gastrocnemius muscle injury. Ovalbumin (OVA), which served as a foreign model antigen, was injected into the hind footpads for determination of the differentiation of OVA-specific Th-cells in the draining popliteal lymph node (pLN). The release of interferon (IFN)-γ from OVA-specific Th-cells was impaired within 24 h after injury and this impairment persisted for at least 7 days. In contrast, the proliferation of OVA-specific Th-cells remained unaffected. Injury did not modulate the function of antigen-presenting cells (APCs) in the pLN. Adoptive transfer of total T-cells from pLNs of injured mice inhibited IFN-γ production by OVA-specific Th-cells in naive mice. Suppressed Th1 priming did not occur in lymphocyte-deficient mice after injury but was restored by administration of T-cells before injury. Moreover, the suppression of Th1 differentiation required the presence of natural killer (NK) cells that were recruited to the pLN after injury; this recruitment was dependent on lymphocytes, toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88). In summary, upon traumatic skeletal muscle injury T-cells and NK cells together prevent the development of protective Th1 immunity. Breaking this co-operation might be a novel approach to reduce the risk of infectious complications after injury., After traumatic skeletal muscle injury, natural killer (NK) cells are recruited to the draining lymph node in a TLR4 (toll-like receptor 4)–myeloid differentiation factor 88 (MyD88)-dependent manner and impair the development of specific T-cell responses. The suppressed T-cell function might increase the susceptibility of severely injured patients to nosocomial infections.

Adaptive immunity, which plays an important role in the development of atherosclerosis, is mediated by major histocompatibility complex (MHC)-dependent antigen presentation. In atherosclerotic lesions, macrophages constitute an important class of antigen-presenting cells that activate adaptive immune responses to oxidized low-density lipoprotein (OxLDL). It has been reported that autophagy regulates adaptive immune responses by enhancing antigen presentation to MHC class II (MHC-II). In a previous study, we have demonstrated that SYK (spleen tyrosine kinase) regulates generation of reactive oxygen species (ROS) and activation of MAPK8/JNK1 in macrophages. Because ROS and MAPK8 are known to regulate autophagy, in this study we investigated the role of SYK in autophagy, MHC-II expression and adaptive immune response to OxLDL. We demonstrate that OxLDL induces autophagosome formation, MHC-II expression, and phosphorylation of SYK in macrophages. Gene knockout and pharmacological inhibitors of NOX2 and MAPK8 reduced OxLDL-induced autophagy. Using bone marrow-derived macrophages isolated from wild-type and myeloid-specific SYK knockout mice, we demonstrate that SYK regulates OxLDL-induced ROS generation, MAPK8 activation, BECN1-BCL2 dissociation, autophagosome formation and presentation of OxLDL-derived antigens to CD4+ T cells. ldlr−/−syk−/− mice fed a high-fat diet produced lower levels of IgG to malondialdehyde (MDA)-LDL, malondialdehyde-acetaldehyde (MAA)-LDL, and OxLDL compared to ldlr−/− mice. These results provide new insights into the mechanisms by which SYK regulates MHC-II expression via autophagy in macrophages and may contribute to regulation of adaptive immune responses in atherosclerosis.

This paper provides an institutional and empirical analysis of the highly concentrated market of academic publishing, characterized by over proportionally high profit margins for publishing companies. The availability of latest research findings is an important issue for researchers, universities and politicians alike. Open access (OA) publication provides a promising but also costly solution to overcome this problem. However, in this paper we argue that OA publication costs are an important, but by far not the only way for academic publishers to gain access to public funding. In contrast, our study provides a comprehensive overview of the channels through which public expenditure benefits big academic publishing companies. Furthermore, we offer the results of an explorative case study, where we estimate the annual financial flows of public expenditures in Austria for the field of social sciences. In all, these expenditures add up to about 66.55 to 103.2 million € a year, which amounts to a fourth of total public funding for this field. Against this background, we contribute to the debate whether and to what extent public subsidies are justified for economically successful companies.

Peer Review is at the heart of scholarly communications and the cornerstone of scientific publishing. However, academia often criticizes the peer review system as non-transparent, biased, arbitrary, a flawed process at the heart of science, leading to researchers arguing with its reliability and quality. These problems could also be due to the lack of studies with the peer-review texts for various proprietary and confidentiality clauses. Peer review texts could serve as a rich source of Natural Language Processing (NLP) research on understanding the scholarly communication landscape, and thereby build systems towards mitigating those pertinent problems. In this work, we present a first of its kind multi-layered dataset of 1199 open peer review texts manually annotated at the sentence level (∼ 17k sentences) across the four layers, viz. Paper Section Correspondence, Paper Aspect Category, Review Functionality, and Review Significance. Given a text written by the reviewer, we annotate: to which sections (e.g., Methodology, Experiments, etc.), what aspects (e.g., Originality/Novelty, Empirical/Theoretical Soundness, etc.) of the paper does the review text correspond to, what is the role played by the review text (e.g., appreciation, criticism, summary, etc.), and the importance of the review statement (major, minor, general) within the review. We also annotate the sentiment of the reviewer (positive, negative, neutral) for the first two layers to judge the reviewer’s perspective on the different sections and aspects of the paper. We further introduce four novel tasks with this dataset, which could serve as an indicator of the exhaustiveness of a peer review and can be a step towards the automatic judgment of review quality. We also present baseline experiments and results for the different tasks for further investigations. We believe our dataset would provide a benchmark experimental testbed for automated systems to leverage on current NLP state-of-the-art techniques to address different issues with peer review quality, thereby ushering increased transparency and trust on the holy grail of scientific research validation. Our dataset and associated codes are available at https://www.iitp.ac.in/~ai-nlp-ml/resources.html#Peer-Review-Analyze.