参考文献

Cells die by necrosis due to excessive chemical or thermal stress,leading to plasma membrane rupture,release of intracellular components and severe inflammation. The clearance of necrotic cell debris is crucial for tissue recovery and injury resolution,however,the underlying mechanisms are still poorly understood,especially in vivo. This study examined the role of complement proteins in promoting clearance of necrotic cell debris by leukocytes and their influence on liver regeneration. We found that independently of the type of necrotic liver injury,either acetaminophen (APAP) overdose or thermal injury,complement proteins C1q and (i)C3b were deposited specifically on necrotic lesions via the activation of the classical pathway. Importantly,C3 deficiency led to a significant accumulation of necrotic debris and impairment of liver recovery in mice,which was attributed to decreased phagocytosis of debris by recruited neutrophils in vivo. Monocytes and macrophages also took part in debris clearance,although the necessity of C3 and CD11b was dependent on the specific type of necrotic liver injury. Using human neutrophils,we showed that absence of C3 or C1q caused a reduction in the volume of necrotic debris that is phagocytosed,indicating that complement promotes effective debris uptake in mice and humans. Moreover,internalization of opsonized debris induced the expression of pro-resolving genes in a C3-dependent manner,supporting the notion that debris clearance favors the resolution of inflammation. In summary,complement activation at injury sites is a pivotal event for necrotic debris clearance by phagocytes and determinant for efficient recovery from tissue injury. Graphical Abstract View Publication

IntroductionAnandamide (AEA) is an endocannabinoid that has recently been recognized as a regulator of various inflammatory diseases as well as cancer. While AEA was thought to predominantly engage cannabinoid (CB) receptors,recent findings suggest that,given its protective anti-inflammatory role in pathological conditions,anandamide may engage not only CB receptors.MethodsIn this study,we studied the role of exogenous AEA in a mouse AirPouch model of acute inflammation by examining immune cell infiltrates by flow cytometry. Human primary immune cells were used to validate findings towards immune cell activation and migration by flow cytometry and bead-based ELISA.ResultsWe found that AEA decreases the acute infiltration of myeloid cells including granulocytes and monocytes into the inflamed area,but unexpectedly increases the number of T cells at the site of inflammation. This was related to AEA signaling through nuclear receptor subfamily 4A (NR4A) transcription factors rather than CB receptors. Exploring regulatory mechanisms in the human system,we found that AEA broadly inhibits the migratory capacity of immune cells,arguing for blocked emigration of T cells from the inflamed tissue. Taking a closer look at the impact of AEA on T cells revealed that AEA profoundly alters the activation and exhaustion status of CD4+ T and CD8+ T cells,thereby strongly inhibiting TH17 responses,while not altering TH1 differentiation.DiscussionThese data suggest that AEA has the potential to block chronic inflammation without influencing crucial anti-viral and anti-microbial immune defense mechanisms,and may therefore be an attractive molecule to interfere with the establishment of chronic inflammation. View Publication

Although chimeric antigen receptor (CAR) T cells are effective against B-lineage malignancies,post-CAR relapse is common,and efficacy in other tumors is limited. These challenges may be addressed through rational manipulations to control CAR T cell function. Here we examine the impact of cognate T cell antigen experience on subsequent CD8+ CAR T cell activity. Prior antigen encounter resulted in superior effector function against leukemia expressing low target antigen density at the expense of reduced proliferative capacity and susceptibility to dysfunction at limiting CAR doses. Distinctive temporal transcriptomic and epigenetic profiles in naive-derived and memory-derived CAR T cells identified RUNX family transcription factors as potential targets to augment the function of naive-derived CD8+ CAR T cells. RUNX2 overexpression enhanced antitumor efficacy of mouse CAR T cells,dependent on prior cell state,and heightened human CAR T cell functions. Our data demonstrate that prior antigen experience of CAR T cells determines functional attributes and amenability to transcription factor-mediated functional enhancement. Here,Fry and colleagues examine the impact of antigen experience on subsequent CD8+ CAR T cell activity during the antileukemia response and show that RUNX2 overexpression enhances antitumor activity of these cells. View Publication

Donor-specific antibodies (DSAs) targeting mismatched human leukocyte antigen (HLA) molecules are one of the principal threats to long-term graft survival in solid organ transplantation. However,many patients with long-term circulating DSAs do not manifest rejection responses,suggesting a degree of heterogeneity in their pathogenicity and related functional activity. Immunologic risk stratification of transplant recipients is complicated by challenges intrinsic to defining alloantibody responses that are potentially pathogenic versus those that are not. Thus,a comprehensive understanding of how human alloantibodies target and interact with donor HLA molecules is vital for the development and evaluation of new strategies aimed at reducing antibody-mediated rejection responses. In this study,we employ hydrogen–deuterium exchange–mass spectrometry (HDX–MS),molecular dynamics (MD) simulations,and advanced biochemical and biophysical methodologies to thoroughly characterize a panel of human monoclonal alloantibodies and define the influence of Fc-region biology,antibody binding kinetics,target antigen density,and structural characteristics on their ability to potentiate the forms of immune effector mechanisms that are strongly implicated in transplant rejection. Our findings have significant implications for our understanding of the key biological determinants that underlie the pathogenicity or lack thereof of human alloantibodies. View Publication

IntroductionUpon infection,T cell-driven B cell responses in GC reactions induce memory B cells and antibody-secreting cells that secrete protective antibodies. How formation of specifically long-lived plasma cells is regulated via the interplay between specific B and CD4+ T cells is not well understood. Generally,antibody levels decline over time after clearance of the primary infection.MethodIn this study,convalescent individuals with stable RBD antibody levels (n=14,“sustainers”) were compared with donors (n=13) with the greatest antibody decline from a cohort of 132. To investigate the role of the cellular immune compartment in the maintenance of antibody levels,SARS-CoV-2-specific responses at 4 to 6 weeks post-mild COVID-19 infection were characterized using deep immune profiling.ResultsBoth groups had similar frequencies of total SARS-CoV-2-specific B and CD4+ T cells. Sustainers had fewer Spike-specific IgG+ memory B cells early after infection and increased neutralizing capacity of RBD antibodies over time,unlike the declining group. However,declining IgG titers correlated with lower frequency of Spike-specific CD4+ T cells.ConclusionThese data suggest that “sustainers” have unique dynamics of GC reactions,yield different outputs of terminally differentiating cells,and improve the quality of protective antibodies over time. This study helps identify factors controlling formation of long-lived PC and sustained antibody responses. View Publication

IntroductionSystemic lupus erythematosus (SLE) is an autoimmune disease characterized by an overactive immune response,particularly involving excessive production of type I interferons. This overproduction is driven by the phosphorylation of IRF7,a crucial factor in interferon gene activation. Current treatments for SLE are often not very effective and can have serious side effects.MethodsOur study introduces clobenpropit,a histamine analogue,as a potential new therapy targeting the CXCR4 receptor to reduce IRF7 phosphorylation and subsequent interferon production. We employed various laboratory techniques to investigate how clobenpropit interacts with CXCR4 and its effects on immune cells from healthy individuals and SLE patients.ResultsClobenpropit binds effectively to CXCR4,significantly inhibiting IRF7 phosphorylation and reducing interferon production. Additionally,clobenpropit lowered levels of pro-inflammatory cytokines in a mouse model of lupus,demonstrating efficacy comparable to the standard treatment,prednisolone.DiscussionThese results suggest that clobenpropit could be a promising new treatment for SLE,offering a targeted approach with potential advantages over current therapies. View Publication

The lungs of people with cystic fibrosis (PwCF) are characterized by recurrent bacterial infections and inflammation. Infections in cystic fibrosis (CF) are left unresolved despite excessive neutrophil infiltration. The role of CFTR in neutrophils is not fully understood. In this study,we aimed to assess which antimicrobial functions are directly impaired by loss of CFTR function in neutrophils. In order to do so,we used a specific inhibitor of CFTR ion channel activity,inh-172. CF neutrophils from PwCF harboring severe CFTR mutations were additionally isolated to further discern CFTR-specific functional defects. We evaluated phagocytosis,reactive oxygen species (ROS) production,neutrophil elastase (NE) and myeloperoxidase (MPO) exocytosis and bacterial killing. The inh-172 model identified decreased acidification of the phagosome,increased bacterial survival and decreased ROS production upon stimulation. In PwCF neutrophils,we observed reduced degranulation of both NE and MPO. When co-culturing neutrophils with CF sputum supernatant and airway epithelial cells,the extent of phagocytosis was reduced,underscoring the importance of recreating an inflammatory environment as seen in PwCF lungs to model immune responses in vitro. Despite low CFTR expression in blood neutrophils,functional defects were found in inh-172-treated and CF neutrophils. The inh-172 model disregards donor variability and allows pinpointing neutrophil functions directly impaired by dysfunctional CFTR.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-024-82535-z. View Publication

Achieving the precise targeting of lentiviral vectors (LVs) to specific cell populations is crucial for effective gene therapy,particularly in cancer treatment where the modulation of the tumor microenvironment can enhance anti-tumor immunity. Programmed cell death protein 1 (PD-1) is overexpressed on activated tumor-infiltrating T lymphocytes,including regulatory T cells that suppress immune responses via FOXP3 expression. We developed PD1-targeted LVs by incorporating the anti-PD1 nanobody nb102c3 into receptor-blinded measles virus H and VSV-Gmut glycoproteins. We assessed the retargeting potential of nb102c3 and evaluated transduction efficiency in activated T lymphocytes. FOXP3 expression was suppressed using shRNA delivered by these LVs. Our results demonstrate that PD1-targeted LVs exerted pronounced tropism towards PD1+ cells,enabling the selective transduction of activated T lymphocytes while sparing naive T cells. The suppression of FOXP3 in Tregs reduced their suppressive activity. PD1-targeted glycoprotein H provided greater specificity,whereas the VSV-Gmut,together with the anti-PD1 pseudoreceptor,achieved higher viral titers but was less selective. Our study demonstrates that PD1-targeted LVs may offer a novel strategy to modulate immune responses within the tumor microenvironment with the potential for developing new therapeutic strategies aimed at enhancing anti-tumor immunity. View Publication

Pathobionts have evolved many strategies to coexist with the host,but how immune evasion mechanisms contribute to the difficulty of developing vaccines against pathobionts is unclear. Meanwhile,Staphylococcus aureus (SA) has resisted human vaccine development to date. Here we show that prior SA exposure induces non-protective CD4+ T cell imprints,leading to the blunting of protective IsdB vaccine responses. Mechanistically,these SA-experienced CD4+ T cells express IL-10,which is further amplified by vaccination and impedes vaccine protection by binding with IL-10Rα on CD4+ T cell and inhibit IL-17A production. IL-10 also mediates cross-suppression of IsdB and sdrE multi-antigen vaccine. By contrast,the inefficiency of SA IsdB,IsdA and MntC vaccines can be overcome by co-treatment with adjuvants that promote IL-17A and IFN-γ responses. We thus propose that IL-10 secreting,SA-experienced CD4+ T cell imprints represent a staphylococcal immune escaping mechanism that needs to be taken into consideration for future vaccine development. Mechanisms of inefficient vaccine protection against pathobionts such as S. aureus (SA) are still unclear. Here the authors show that prior SA exposure induces non-protective CD4+ T cells,which impair IsdB vaccine protection by IL-10 secretion and IL-17A suppression,whereas IL-17A promoting adjuvant CAF01 overcomes this dilemma. View Publication

AbstractChlamydia genital infection caused by Chlamydia trachomatis is the most common bacterial sexually transmitted disease worldwide. A mouse model has been developed in our laboratory to better understand the effect of cold-induced stress on chlamydia genital infection and immune response. However,the stress mechanism affecting the host response to Chlamydia muridarum genital infection remains unclear. Here,we demonstrate a role for the beta2-adrenergic receptor (β2-AR),which binds noradrenaline and modulates the immune response against chlamydia genital infection in a mouse model. A successful β2-AR homozygous knockout (KO) mouse model was used to study the infection and analyze the immune response. Our data show that stressed mice lacking the β2-AR are less susceptible to C. muridarum genital infection than controls. A correlation was obtained between lower organ load and higher interferon-gamma production by CD4+ and CD8+ cells of the KO mice. Furthermore,exposure of CD4+ T cells to noradrenaline alters the production of cytokines in mice during C. muridarum genital infection. This study suggests that the blockade of β2-AR signaling could be used to increase resistance to chlamydia genital infection. We value the β2-AR KO as a viable model that can provide reproducible results in investigating medical research,including chlamydia genital infection. Deficiency in a receptor leads to a reduced disease of chlamydia in a mouse model. View Publication