Over-expression of programmed death-ligand 1 and programmed death-1 on antigen-presenting cells as a predictor of organ dysfunction and mortality during early sepsis: a prospective cohort study

BACKGROUND:This study aimed to explore the changes of programmed death-ligand 1(PDL1)and programmed death-1(PD-1)expression on antigen-presenting cells(APCs)and evaluate their association with organ failure and mortality during early sepsis.METHODS:In total,40 healthy controls and 198 patients with sepsis were included in this study.Peripheral blood was collected within the first 24 h after the diagnosis of sepsis.The expression of PDL1 and PD-1 was determined on APCs,such as B cells,monocytes,and dendritic cells(DCs),by flow cytometry.Cytokines in plasma,such as interferon-γ(IFN-γ),tumor necrosis factor-α(TNF-α),interleukin-4(IL-4),IL-6,IL-10,and IL-17A were determined by Luminex assay.RESULTS:PD-1 expression decreased significantly on B cells,monocytes,myeloid DCs(mDCs),and plasmacytoid DCs(pDCs)as the severity of sepsis increased.PD-1 expression was also markedly decreased in non-survivors compared with survivors.In contrast,PD-L1 expression was markedly higher on mDCs,pDCs,and monocytes in patients with sepsis than in healthy controls and in non-survivors than in survivors.The PD-L1 expression on APCs(monocytes and DCs)was weakly related to organ dysfunction and infl ammation.The area under the receiver operating characteristic curve(AUC)of the PD-1 percentage of monocytes(monocyte PD-1%)+APACHE II model(0.823)and monocyte PD-1%+SOFA model(0.816)had higher prognostic value than other parameters alone.Monocyte PD-1%was an independent risk factor for 28-day mortality.CONCLUSION:The severity of sepsis was correlated with PD-L1 or PD-1 over-expression on APCs.PD-L1 in monocytes and DCs was weakly correlated with infl ammation and organ dysfunction during early sepsis.The combination of SOFA or APACHE II scores with monocyte PD-1%could improve the prediction ability for mortality.

Targeting epidermal Langerhans cells by epidermal powder immunization

Immune reactions to foreign or self-antigens lead to protective immunity and, sometimes, immune disorders such as allergies and autoimmune diseases. Antigen presenting cells (APC) including epidermal Langerhans cells (LCs) play an important role in the course and outcome of the immune reactions. Epidermal powder immunization (EPI) is a technology that offers a tool to manipulate the LCs and the potential to harness the immune reactions towards prevention and treatment of infectious diseases and immune disorders.

Inducible expression of endomorphins in murine dendritic cells

Bone marrow precursor cells were extracted from C57BL/6J mice aged 7-8 weeks, and dendritic cells were purified using anti-CD1 lc （a specific marker for dendritic cells） antibody-coated magnetic beads. Immunofluorescence staining revealed that the expression levels of endomorphin-1 and endomorphin-2 were upregulated in dendritic cells activated by lipopolysaccharide. An enzyme Jmmunoassay showed that lipopolysaccharide and other Toll-like receptor ligands promoted the secretion of endomorphin-1 and endomorphin-2 from activated dendritic cells. [3H]-thymidine incorporation demonstrated that endomorphin-1 and endomorphin-2 both inhibited the proliferation of T lymphocyte induced by activated dendritic cells. Furthermore, this immunosuppressive effect was blocked by CTOP, a specific antagonist of IJ-opioid receptors. Our experimental findings indicate that activated dendritic cells can induce the expression and secretion of endomorphins, and that endomorphins suppress T lymphocyte proliferation through activation of iJ-opioid receptors.

Co-Inhibitors of Second Signal of Lymphocyte Response in Human Renal Transplants: PD-L2, GITR, and ILT-2/3/5 Positive Cells from Aspiration Biopsies Associate with Acute Rejection-Freedom

Following organ transplantation, the outcome of the encounter between an APC and a T lymphocyte is strongly dependent on the presence of costimulatory and co-inhibitory molecules, the former associated with allograft rejection and the latter with allograft acceptance. We evaluated the expression of PD-L2, GITR, ILT-2/3/5, and ILT-4 on graft-infiltrating cells procured by Fnab from human KTx under different immunosuppressive regimens. Methods: Fnab biopsies were performed on days 7 or 14 - 30 in stable KTx and on the day of acute rejection diagnosis. Cytopreparations were studied by the enzymatic avidin biotin complex staining. Results: Acute rejection group showed a significant down-regulated expression of PD-L2, GITR, and ILT-2/3/5 as compared to stable group, while for ILT-4 we did not find significant difference. Anti-IL2αR and rapamicyn treatment trend to down-regulate ILT-4 expression, although meaningless. A significantly positive correlation was observed between PD-L2 and GITR expression in Fnab. The PPV for acute rejection diagnosis for both PD-L2 and GITR was clearly above 0.8. Conclusions: Our findings point to an early entrance of cells expressing PD-L2, GITR and ILT-2/3/5 inside human KTx who are going to remain rejection-free. Both PD-L2 and GITR shared a high ability to rule-in and rule-out acute rejection.

Diverse immune cell profles in ASFV-associated lymphopenia

Pathogenic African swine fever virus(ASFV)remains a lethal causative agent in the domestic pig industry,which poses a burden on the swine market and causes substantial socioeconomic losses worldwide.Currently,there are no commercially efcacious vaccines or specifc treatments available for ASF prevention and control.Unfortunately,little is known about the swine immune response upon ASFV infection.Here,we investigated the host immune response discrepancy induced by the feld moderately virulent strain ASFV HB-2208 among healthy,diseased and asymptomatic pigs.In the peripheral blood of diseased swine,lymphopenia is caused by the massive loss of bystander lymphocytes,such asγδT cells,B cells and CD4^(+)T cells.Conversely,ASFV has a strong tropism for the mononuclear phagocyte system(MPS)and partial dendritic cells(DCs),whose antigen-presenting ability is impeded by the downregulation of CD80 and MHC I.However,no signifcant diference in the number of CD8α^(high) T cells was detected,whereas the frequencies of NK cells,NKT cells,and regulatory T cells(Tregs)were signifcantly increased.Additionally,an in vitro model was established with a coculture of primary pulmonary alveolar macrophages(PAMs)and peripheral blood mononuclear cells(PBMCs),which signifcantly reducedγδT cells,B cells and CD4^(+)T cells and increased Tregs.The diferentiated immune response might aid in enhancing the understanding of ASFV pathogenesis in suids and provide insights into the mechanism of ASFV-induced lymphopenia for further studies.

Antigen-presenting effects of effector memory Vγ9Vδ2 T cells in rheumatoid arthritis

Rheumatoid arthritis is an autoimmune disease that primarily affects the limbs, but the pathogenic mechanism remains unclear. 78 T cells, a T-cell subpopulation, are characterized by multiple biological functions and associated with a variety of diseases. This study investigated the antigen-presenting effects of γδ2 cells and their relationship with rheumatoid arthritis development. We found that Vγ9Vδ2 T cells （the predominant subtype of γδ T cells in peripheral blood） were activated by isopentenyl pyrophosphate to continuously proliferate and differentiate into effector memory cells. The effector memory Vγ9Vδ2 T cells exhibited phenotypic characteristics of specific antigen-presenting cells, including high HLA-DR and CD80/86 expression. These Vγ9Vδ2 T cells could present soluble antigens and synthetic peptides to CD4＋ T cells. Vγ9Vδ2 T cells with different phenotypes showed different cytokine secretion patterns. Effector memoryVγ9Vδ2 T cells simultaneously secreted not only interferon （IFN）-γbut also IL-17. The peripheral blood and joint synovial fluid from RA patients contained numerous heterogeneous γδ T cells that were predominantly effector memory Vγ9Vδ2 T cells with the ability to secrete inflammatory factors. We also found that γδ T cells had a similar antigen-presenting capability to B cells. These results suggest that during the development of rheumatoid arthritis, 78 T cells can aggravate immune dysfunction and produce abnormal immune damage by secreting cytokines and inducing inflammatory cells to participate in synergistic inflammatory responses. Furthermore, γδ T cells can behave similarly to B cells to present viral peptides and autoantigen peptides to CD4＋ T cells, thus sustaining CD4＋ T-cell activation.

Establishment and Characterization of a Cell Based Artificial Antigen-Presenting Cell for Expansion and Activation of CD8^+ T Cells Ex Vivo

Artificial antigen-presenting cells are expected to stimulate the expansion and acquisition of optimal therapeutic features of T cells before infusion. Here CD32 that binds to a crystallizable fragment of IgG monoclonal antibody was genetically expressed on human K562 leukemia cells to provide a ligand for T-cell receptor. CD86 and 4-1BBL, which are ligands of co-stimulating receptors of CD28 and 4-1BB, respectively, were also expressed on K562 cells. Then we accomplished the artificial antigen-presenting cells by coupling K32/CD86/4-1BBL cell with OKT3 monoclonal antibody against CD3, named K32/CD86/4-1BBL/OKT3 cells. These artificial modified cells had the abilities of inducing CD8^＋ T cell activation, promoting CD8^＋ T cell proliferation, division, and long-term growth, inhibiting CD8^＋ T cell apoptosis, and enhancing CD8^＋ T cell secretion of IFN-T and perforin. Furthermore, antigen-specific cytotoxic T lymphocytes could be retained in the culture stimulated with K32/CD86/4-1BBL/OKT3 cells at least within 28 days. This approach was robust, simple, reproducible and economical for expansion and activation of CD8^＋ T cells and may have important therapeutic implications for adoptive immunotherapy. Cellular ＆ Molecular Immunology.

Cell-type specific regulation of MARCH1 E3 ubiquitin ligase by the anti-inflammatory cytokine IL-10

Membrane-associated RING-CH-1 (MARCH1) is an E3 ubiquitin ligase which targets MHC-II, CD86 and various other molecules for degradation. It is one of the most efficient post-translational regulators of antigen presentation. MARCH1 is expressed in resting immature dendritic cells and B cells but can be induced in other cell types. While activation of most immune cells results in a reduction in MARCH1 gene expression, its anti-inflammatory properties are highlighted by its induction in response to IL-10. Here, we review what is known about the regulation of MARCH1 gene expression in response to IL-10 by various immune cells. We speculate on the role of MARCH1 ininfection, its differential expression pattern and the promise that this E3 ubiquitin ligase holds to influence immune responses and mitigate immune pathologies.

Criculating fibrocytes： a potent cell population in antigen-presenting and wound healing

Fibrocytes are bone marrow-derived mesenchymal progenitors that co-express hematopoietic cell antigens and markers of monocytic lineage as well as fibroblast products. During wound healing, fibrocytes have been found to possess the ability of antigen-presentation to naive T cells in the inflammatory phase. Moreover, they can promote the endothelial cell proliferation, migration and angiogenesis by secreting several proteins. Fibrocytes can further differentiate into mature mesenchymocyte lineage, such as fibroblasts, myofibroblasts and adipocytes, and they may represent the systemic source of myofibroblasts that exert a contractile force required to close tissue wounds. A deep understanding of the mechanism involved in fibrocyte migration and differentiation may lead to the development of a novel theory of normal physiology and pathology.

A two-pronged strategy utilizing exosomes extracted from antigenpresenting cells to combat hepatitis B

Chronic hepatitis B(CHB)is consistently challenging to conquer with numerous complications and fatalities.Despite the effectiveness of antiviral therapies in suppressing hepatitis B virus(HBV)replication,there is an urgent need for novel and more effective treatment modalities.Current strategies predominantly emphasize immune activation but still face challenges in sufficiently eliciting T cell responses.Taking into account the targeted delivery of nanoparticles to the liver and spleen via intravenous injection,we have proposed a dual-pronged therapeutic strategy based on antigen-presenting cells(APCs)-derived exosomes.Specifically,exosomes targeted to the spleen can activate specific immune responses,while those targeted to the liver can modulate or reverse the liver’s immunosuppressive microenvironment.After immunization,exosome formulations exhibit the remarkable ability to effectively activate APCs,thereby triggering the proliferation of CD8^(+)T cells.Simultaneously,they also play an immunoregulatory role by converting M2 macrophages into M1 macrophages.This two-pronged therapeutic strategy precisely addresses the issues of T cell dysfunction and immune suppression,both characteristic features of CHB patients.When combined with Aluminum(Alum)-adjuvanted vaccine,these exosome formulations not only demonstrate a high level of cellular immune response but also secrete specific antibodies comparable to those induced by Alum adjuvant.This combined approach effectively enhances both cellular and humoral immunity,offering a promising avenue for the development of therapeutic hepatitis B vaccines based on exosome formulations.

STING negatively regulates allogeneic T-cell responses by constraining antigen-presenting cell function

Stimulator of interferon genes(STING)-mediated innate immune activation plays a key role in tumor-and self-DNA-elicited antitumor immunity and autoimmunity.However,STING can also suppress tumor immunity and autoimmunity.STING signaling In host nonhematopoietic cells was reported to either protect against or promote graft-versus-host disease(GVHD),a major complication of allogeneic hematopoietic cell transplantation(allo-HCT).Host hematopoietic antigen-presenting cells(APCs)play key roles in donor T-cell priming during GVHD initiation.However,how STING regulates host hematopoietic APCs after allo-HCT remains unknown.We utilized murine models of allo-HCT to assess the role of STING in hematopoietic APCs.STING-deficient recipients developed more severe GVHD after major histocompatibility complex-mismatched allo-HCT.Using bone marrow chimeras,we found that STING deficiency in host hematopoietic cells was primarily responsible for exacerbating the disease.Furthermore,STING on host CD11c+cells played a dominant role in suppressing allogeneic T-cell responses.Mechanistically,STING deficiency resulted in increased survival,activation,and function of APCs,including macrophages and dendritic cells.Consistently,constitutive activation of STING attenuated the survival,activation,and function of APCs isolated from STING V154M knock-in mice.STING-deficient APCs augmented donor T-cell expansion,chemokine receptor expression,and migration into intestinal tissues,resulting in accelerated/exacerbated GVHD.Using pharmacologic approaches,we demonstrated that systemic administration of a STING agonist(bis-(3'-5')-cyclic dimeric guanosine monophosphate)to recipient mice before transplantation significantly reduced GVHD mortality.In conclusion,we revealed a novel role of STING in APC activity that dictates T-cell allogeneic responses and validated STING as a potential therapeutic target for controlling GVHD after allo-HCT.

“干细胞生物学”课程的教师团队讲座式教学方法探索

初步探索教师团队讲座式教学方法在“干细胞生物学”课程中的应用。课程特色地引入干细胞领域高水平教师团队联合授课,紧跟干细胞国际科技前沿动态,提高学生的科研敏锐度,并融合思政元素,培养具有创新思维的高素质人才。经过课堂实践,证明该教学方法对于引导学生具备创新思维、树立正确的“三观”及提高科研能力有良好的效果。教师团队讲座式教学方法是一种行之有效的教学模式,可优先在学院其他课程教学中试点推广,采集充足的样本及数据后,可对该教学方法进一步优化。

以专业特色推进细胞生物学课程改革

细胞生物学是目前生命科学领域发展最快最活跃的学科之一,该领域的很多发现都获得了诺贝尔奖。药学作为一门应用学科,与生命科学密切相关,尤其在单克隆抗体药物成为药物研发热点的今天,药学从业人员掌握细胞生物学相关理论技术尤其显得必要。作者对生物制药专业的细胞生物学课程进行了教学改革,改革的宗旨是结合行业热点与学校专业特色,培养具有竞争力的专业人才。

依托医学细胞生物学课程,以专业特色推进干细胞教学

干细胞研究是当今生命医学领域的前沿,由于其在生物和临床医学领域有非常强的应用潜力和理论价值受到世界各国的高度关注。以医学细胞生物学课程为依托,专业化、针对性地进行干细胞生物学的教学,使得医学院校各个专业学生快速地理解专业相关干细胞生物学基础知识和前沿进展,是培养专业人才、提高教学质量的有效途径。

从中国“干细胞治疗”热论干细胞临床转化中的伦理和管理问题

本文试图对我国(大陆)21世纪初开始并流行至今的"干细胞治疗"热提供一个比较全面的概览,并对这种具有中国特色的社会现象做出初步的解释,同时讨论了干细胞临床转化中的临床伦理、研究伦理和管理问题,最后扼要总结了我们从中应该吸取的几点教训。

新兴技术竞争优势的测度方法研究——基于四象限图示和雷达图示分析方法

探索新兴技术竞争优势的测度方法,有助于我们把握技术前沿的竞争态势,推动科技成果的转化。采用四象限图示分析方法和雷达图示分析方法,借助Relecura专业知识产权分析平台,以细胞免疫治疗为实证,对技术主体的综合竞争优势和高产机构在主要技术领域、子领域、IPC代码的竞争优势进行了分析。就专利技术战略布局的前瞻性指标而言,美国国立卫生研究院和美国卫生与公众服务部两个机构最具有前瞻性。就创造高价值专利的执行力而言,美国国立卫生研究院和Celera公司具有相对比较强的创造高价值专利技术的执行力。高产机构在主要技术领域的竞争优势各异,美国卫生与公众服务部在更多的技术子领域和IPC代码具有优势。

“通专结合”导向下“细胞生物学”课程体系建设新探索——以江西中医药大学为例

通识教育与专业教育相结合是"全人"培养的核心,也是高等教育发展的必然需求。如何在具体课程中实践"通专结合"的理论?本文以江西中医药大学细胞生物学课程为例,提出了"通专结合"理念指导下该课程需实现的目标群,并通过构建"三位一体"课程体系来具体实践之,取得了良好的教学效果。本文具有一定的探索性和创新性,对其他理工科类课程具有启发意义。

课程思政在医学细胞生物学教学中的探索与实践

实施课程思政是高校实现立德树人、培养中国特色社会主义合格建设者和接班人的重要途径。医学细胞生物学是临床医学本科的一门学科基础课程,在教学过程中,通过增强教师立德树人意识并培训、深入挖掘课程知识体系中的思政元素、密切联系国情和社情等措施,砥砺学生的家国情怀、培养学生的职业素养、增强学生的民族自豪感和责任担当意识,打造更有温度、更有态度的专业课教学体系,提高人才培养质量。

An imbalance between innate and adaptive immune cells at the maternal-fetal interface occurs prior to endotoxin-induced preterm birth

Preterm birth （PTB） is the leading cause of neonatal morbidity and mortality worldwide. A transition from an anti-inflammatory state to a pro-inflammatory state in the mother and at the maternal-fetal interface has been implicated in the pathophysiology of microbial-induced preterm labor. However, it is unclear which immune cells mediate this transition. We hypothesized that an imbalance between innate and adaptive immune cells at the maternal-fetal interface will occur prior to microbial-induced preterm labor. Using an established murine model of endotoxin-induced PTB, our results demonstrate that prior to delivery there is a reduction of CD4 ＋ regulatory T cells （Tregs） in the uterine tissues. This reduction is neither linked to a diminished number of Tregs in the spleen, nor to an impaired production of ILIO, CCL17, or CCL22 by the uterine tissues. Endotoxin administration to pregnant mice does not alter effector CD4＋ T cells at the maternal-fetal interface. However, it causes an imbalance between Tregs （CD4＋ and CD8＋）, effector CD8＋ T cells, and Th17 cells in the spleen. In addition, endotoxin administration to pregnant mice leads to an excessive production of CCL2, CCL3, CCL17, and CCL22 by the uterine tissues as well as abundant neutrophils. This imbalance in the uterine microenvironment is accompanied by scarce APC-like cells such as macrophages and MHC II ＋ neutrophils. Collectively, these results demonstrate that endotoxin administration to pregnant mice causes an imbalance between innate and adaptive immune cells at the maternal-fetal interface.

STING-activating dendritic cell-targeted nanovaccines that evoke potent antigen cross-presentation for cancer immunotherapy

Recently,nanovaccine-based immunotherapy has been robustly investigated due to its potential in governing the immune response and generating long-term protective immunity.However,the presentation of a tumor peptide-major histocompatibility complex to T lymphocytes is still a challenge that needs to be addressed for eliciting potent antitumor immunity.Type 1 conventional dendritic cell(cDC1)subset is of particular interest due to its pivotal contribution in the cross-presentation of exogenous antigens to CD8+T cells.Here,the DC-derived nanovaccine(denoted as Si9GM)selectively targets cDC1s with marginal loss of premature antigen release for effective stimulator of interferon genes(STING)-mediated antigen cross-presentation.Bone marrow dendritic cell(BMDC)-derived membranes,conjugated to cDC1-specific antibody(αCLEC9A)and binding to tumor peptide(OVA257-264),are coated onto dendrimer-like polyethylenimine(PEI)-grafted silica nanoparticles.Distinct molecular weight-cargos(αCLEC9A-OVA257-264 conjugates and 2′3′-cGAMP STING agonists)are loaded in hierarchical center-radial pores that enables lysosome escape for potent antigen-cross presentation and activates interferon type I,respectively.Impressively,Si9GM vaccination leads to the upregulation of cytotoxic T cells,a reduction in tumor regulatory T cells(Tregs),M1/M2 macrophage polarization,and immune response that synergizes with αPD-1 immune checkpoint blockade.This nanovaccine fulfills a dual role for both direct T cell activation as an artificial antigen-presenting cell and DC subset maturation,indicating its utility in clinical therapy and precision medicine.