技术资料

SummaryThe existing suite of therapies for bone diseases largely act to prevent further bone loss but fail to stimulate healthy bone formation and repair. We describe an endogenous osteopeptide (PEPITEM) with anabolic osteogenic activity,regulating bone remodeling in health and disease. PEPITEM acts directly on osteoblasts through NCAM-1 signaling to promote their maturation and formation of new bone,leading to enhanced trabecular bone growth and strength. Simultaneously,PEPITEM stimulates an inhibitory paracrine loop: promoting osteoblast release of the decoy receptor osteoprotegerin,which sequesters RANKL,thereby limiting osteoclast activity and bone resorption. In disease models,PEPITEM therapy halts osteoporosis-induced bone loss and arthritis-induced bone damage in mice and stimulates new bone formation in osteoblasts derived from patient samples. Thus,PEPITEM offers an alternative therapeutic option in the management of diseases with excessive bone loss,promoting an endogenous anabolic pathway to induce bone remodeling and redress the imbalance in bone turnover. Graphical abstract Highlights•PEPITEM exerts anabolic osteogenic activity to regulate osteoblast-osteoclast coupling•PEPITEM acts directly on osteoblasts to promote formation of new and stronger bone•PEPITEM stimulates an inhibitory paracrine loop via OPG to limit bone resorption•PEPITEM therapy halts disease-induced bone loss in vivo Lewis and Frost et al. identify the anabolic activity of an endogenous osteopeptide (PEPITEM),revealing the cellular and molecular mechanisms by which PEPITEM regulates bone remodeling in vitro and in preclinical disease models,to promote new bone formation. They suggest that PEPITEM offers an alternative therapeutic option for bone loss diseases. View Publication

IntroductionRecently,more and more research illustrated the importance of inducing CD4+ T helper type (Th)-1 dominant immunity for the success of tumor immunotherapy. Our prior studies revealed the crucial role of CD4+ Th1 cells in orchestrating systemic and durable antitumor immunity,which contributes to the satisfactory outcomes of the novel cryo-thermal therapy in the B16F10 tumor model. However,the mechanism for maintaining the cryo-thermal therapy-mediated durable CD4+ Th1-dominant response remains uncovered. Additionally,cryo-thermal-induced early-stage CD4+ Th1-dominant T cell response showed a correlation with the favorable prognosis in patients with colorectal cancer liver metastasis (CRCLM). We hypothesized that CD4+ Th1-dominant differentiation induced during the early stage post cryo-thermal therapy would affect the balance of CD4+ subsets at the late phase.MethodsTo understand the role of interferon (IFN)-γ,the major effector of Th1 subsets,in maintaining long-term CD4+ Th1-prone polarization,B16F10 melanoma model was established in this study and a monoclonal antibody was used at the early stage post cryo-thermal therapy for interferon (IFN)-γ signaling blockade,and the influence on the phenotypic and functional change of immune cells was evaluated.ResultsIFNγ at the early stage after cryo-thermal therapy maintained long-lasting CD4+ Th1-prone immunity by directly controlling Th17,Tfh,and Tregs polarization,leading to the hyperactivation of Myeloid-derived suppressor cells (MDSCs) represented by abundant interleukin (IL)-1β generation,and thereby further amplifying Th1 response.DiscussionOur finding emphasized the key role of early-phase IFNγ abundance post cryo-thermal therapy,which could be a biomarker for better prognosis after cryo-thermal therapy. View Publication

Stimulator of interferon genes (STING) is a central component of the cytosolic nucleic acids sensing pathway and as such master regulator of the type I interferon response. Due to its critical role in physiology and its’ involvement in a variety of diseases,STING has been a focus for drug discovery. Targeted protein degradation (TPD) has emerged as a promising pharmacology for targeting previously considered undruggable proteins by hijacking the cellular ubiquitin proteasome system (UPS) with small molecules. Here,we identify AK59 as a STING degrader leveraging HERC4,a HECT-domain E3 ligase. Additionally,our data reveals that AK59 is effective on the common pathological STING mutations,suggesting a potential clinical application of this mechanism. Thus,these findings introduce HERC4 to the fields of TPD and of compound-induced degradation of STING,suggesting potential therapeutic applications. In this paper,Mutlu et al. identifies a STING degrader,AK59,which inhibits downstream cGAS/STING activity through STING degradation employing a HECT-domain E3 ligase HERC4 and proteasomal ubiquitination pathway. View Publication

Although Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) have been approved in multiple diseases,including BRCA1/2 mutant breast cancer,responses are usually transient requiring the deployment of combination therapies for optimal efficacy. Here we thus explore mechanisms underlying sensitivity and resistance to PARPi using two intrinsically PARPi sensitive (T22) and resistant (T127) syngeneic murine breast cancer models in female mice. We demonstrate that tumor associated macrophages (TAM) potentially contribute to the differential sensitivity to PARPi. By single-cell RNA-sequencing,we identify a TAM_C3 cluster,expressing genes implicated in anti-inflammatory activity,that is enriched in PARPi resistant T127 tumors and markedly decreased by PARPi in T22 tumors. Rps19/C5aR1 signaling is selectively elevated in TAM_C3. C5aR1 inhibition or transferring C5aR1hi cells increases and decreases PARPi sensitivity,respectively. High C5aR1 levels in human breast cancers are associated with poor responses to immune checkpoint blockade. Thus,targeting C5aR1 may selectively deplete pro-tumoral macrophages and engender sensitivity to PARPi and potentially other therapies. PARP inhibitors (PARPi) have been approved for the treatment of metastatic triple-negative breast cancer (BC),however resistance and recurrence are often observed. Here,in preclinical models of BRCA1/2 wild type and homologous recombination competent BC,the authors show that C5aR1-positive tumor associated macrophages are associated with PARPi-resistance,suggesting targeting C5aR1 as a therapeutic option. View Publication

SummarySeptic patients with worst clinical prognosis have increased circulating immature granulocytes (IG),displaying limited phagocytosis and reactive oxygen species (ROS) production. Here,we developed an ex vivo model of incubation of human granulocytes,from septic patients or healthy donors,with Escherichia coli. We showed that the ROS production in Sepsis-IG is lower due to decreased activation and protein expression of the NADPH oxidase complex. We also demonstrated that the low level of ROS production and lower phagocytosis of IG in sepsis induce the bacterial SOS response,leading to the expression of the SOS-regulated quinolone resistance gene qnrB2. Without antimicrobial pressure,the sepsis immune response alone may promote antibiotic resistance expression. Graphical abstract Highlights•Immature granulocytes in sepsis have decreased phagocytosis and ROS production•SOS response is induced in granulocyte-phagocyted bacteria and is ROS dependent•The level of bacterial SOS induction depends on granulocyte maturation and priming•Phagocyted bacteria induce SOS-dependent quinolone resistance qnrB2 expression Immunology; Microbiology; Bacteriology View Publication

BackgroundNatural killer (NK) cells are key effector cells of antitumor immunity. However,tumors can acquire resistance programs to escape NK cell-mediated immunosurveillance. Identifying mechanisms that mediate this resistance enables us to define approaches to improve immune-mediate antitumor activity. In previous studies from our group,a genome-wide CRISPR-Cas9 screen identified Charged Multivesicular Body Protein 2A (CHMP2A) as a novel mechanism that mediates tumor intrinsic resistance to NK cell activity.MethodsHere,we use an immunocompetent mouse model to demonstrate that CHMP2A serves as a targetable regulator of not only NK cell-mediated immunity but also other immune cell populations. Using the recently characterized murine 4MOSC model system,a syngeneic,tobacco-signature murine head and neck squamous cell carcinoma model,we deleted mCHMP2A using CRISPR/Cas9-mediated knock-out (KO),following orthotopic transplantation into immunocompetent hosts.ResultsWe found that mCHMP2A KO in 4MOSC1 cells leads to more potent NK-mediated tumor cell killing in vitro in these tumor cells. Moreover,following orthotopic transplantation,KO of mCHMP2A in 4MOSC1 cells,but not the more immune-resistant 4MOSC2 cells enables both T cells and NK cells to better mediate antitumor activity compared with wild type (WT) tumors. However,there was no difference in tumor development between WT and mCHMP2A KO 4MOSC1 or 4MOSC2 tumors when implanted in immunodeficient mice. Mechanistically,we find that mCHMP2A KO 4MOSC1 tumors transplanted into the immunocompetent mice had significantly increased CD4+T cells,CD8+T cells. NK cell,as well as fewer myeloid-derived suppressor cells (MDSC).ConclusionsTogether,these studies demonstrate that CHMP2A is a targetable inhibitor of cellular antitumor immunity. View Publication

SummaryDrug resistance threatens the effective control of infections,including parasitic diseases such as leishmaniases. Neutrophils are essential players in antimicrobial control,but their role in drug-resistant infections is poorly understood. Here,we evaluated human neutrophil response to clinical parasite strains having distinct natural drug susceptibility. We found that Leishmania antimony drug resistance significantly altered the expression of neutrophil genes,some of them transcribed by specific neutrophil subsets. Infection with drug-resistant parasites increased the expression of detoxification pathways and reduced the production of cytokines. Among these,the chemokine CCL3 was predominantly impacted,which resulted in an impaired ability of neutrophils to attract myeloid cells. Moreover,decreased myeloid recruitment when CCL3 levels are reduced was confirmed by blocking CCL3 in a mouse model. Collectively,these findings reveal that the interplay between naturally drug-resistant parasites and neutrophils modulates the infected skin immune microenvironment,revealing a key role of neutrophils in drug resistance. Graphical abstract Highlights•Drug-resistant parasites induce distinct neutrophil transcriptional programs•Meglumine-antimoniate-resistant (MAR) Leishmania limits neutrophil chemokine release•Infection with MAR parasites impairs CCL3-driven early myeloid cell recruitment Immunology; Parasitology View Publication

SummaryHispanic/Latino children have the highest risk of acute lymphoblastic leukemia (ALL) in the US compared to other racial/ethnic groups,yet the basis of this remains incompletely understood. Through genetic fine-mapping analyses,we identified a new independent childhood ALL risk signal near IKZF1 in self-reported Hispanic/Latino individuals,but not in non-Hispanic White individuals,with an effect size of ∼1.44 (95% confidence interval = 1.33–1.55) and a risk allele frequency of ∼18% in Hispanic/Latino populations and <0.5% in European populations. This risk allele was positively associated with Indigenous American ancestry,showed evidence of selection in human history,and was associated with reduced IKZF1 expression. We identified a putative causal variant in a downstream enhancer that is most active in pro-B cells and interacts with the IKZF1 promoter. This variant disrupts IKZF1 autoregulation at this enhancer and results in reduced enhancer activity in B cell progenitors. Our study reveals a genetic basis for the increased ALL risk in Hispanic/Latino children. Graphical abstract Highlights•IKZF1 variants contribute to the increased risk of ALL in Hispanic/Latino children•Risk allele is associated with Indigenous American ancestry and underwent selection•Risk variant impacts IKZF1 enhancer that is selectively active in B cell development•Risk allele reduces enhancer activity,chromatin accessibility,and IKZF1 expression Genetic fine-mapping across the IKZF1 gene revealed a variant associated with childhood ALL that contributes to the increased risk of this disease in Hispanic/Latino individuals. The ALL risk allele reduces enhancer activity and IKZF1 expression specifically in B cell progenitors,likely resulting in stalled B cell development and an increased risk of ALL. View Publication

α-Defensin 1-3 (DEFA1A3) are host antimicrobial peptides with potent innate immune functions during infectious diseases. Differential UTI risk has been linked to DEFA1A3 DNA polymorphisms. This study elucidates mechanisms of DEFA1A3 gene dose–dependent protection against UTI pathogenesis. Antimicrobial peptides (AMPs) are host defense effectors with potent neutralizing and immunomodulatory functions against invasive pathogens. The AMPs α-Defensin 1-3/DEFA1A3 participate in innate immune responses and influence patient outcomes in various diseases. DNA copy-number variations in DEFA1A3 have been associated with severity and outcomes in infectious diseases including urinary tract infections (UTIs). Specifically,children with lower DNA copy numbers were more susceptible to UTIs. The mechanism of action by which α-Defensin 1-3/DEFA1A3 copy-number variations lead to UTI susceptibility remains to be explored. In this study,we use a previously characterized transgenic knock-in of the human DEFA1A3 gene mouse to dissect α-Defensin 1-3 gene dose–dependent antimicrobial and immunomodulatory roles during uropathogenic Escherichia coli (UPEC) UTI. We elucidate the relationship between kidney neutrophil– and collecting duct intercalated cell–derived α-Defensin 1-3/DEFA1A3 expression and UTI. We further describe cooperative effects between α-Defensin 1-3 and other AMPs that potentiate the neutralizing activity against UPEC. Cumulatively,we demonstrate that DEFA1A3 directly protects against UPEC meanwhile impacting pro-inflammatory innate immune responses in a gene dosage–dependent manner. View Publication

AbstractBacillus anthracis peptidoglycan (PGN) is a major component of the bacterial cell wall and a key pathogen-associated molecular pattern contributing to anthrax pathology,including organ dysfunction and coagulopathy. Increases in apoptotic leukocytes are a late-stage feature of anthrax and sepsis,suggesting there is a defect in apoptotic clearance. In this study,we tested the hypothesis that B. anthracis PGN inhibits the capacity of human monocyte-derived macrophages (MΦ) to efferocytose apoptotic cells. Exposure of CD163+CD206+ MΦ to PGN for 24 h impaired efferocytosis in a manner dependent on human serum opsonins but independent of complement component C3. PGN treatment reduced cell surface expression of the proefferocytic signaling receptors MERTK,TYRO3,AXL,integrin αVβ5,CD36,and TIM-3,whereas TIM-1,αVβ3,CD300b,CD300f,STABILIN-1,and STABILIN-2 were unaffected. ADAM17 is a major membrane-bound protease implicated in mediating efferocytotic receptor cleavage. We found multiple ADAM17-mediated substrates increased in PGN-treated supernatant,suggesting involvement of membrane-bound proteases. ADAM17 inhibitors TAPI-0 and Marimastat prevented TNF release,indicating effective protease inhibition,and modestly increased cell-surface levels of MerTK and TIM-3 but only partially restored efferocytic capacity by PGN-treated MΦ. We conclude that human serum factors are required for optimal recognition of PGN by human MΦ and that B. anthracis PGN inhibits efferocytosis in part by reducing cell surface expression of MERTK and TIM-3. View Publication

SummaryFollicular lymphoma (FL) is an indolent non-Hodgkin lymphoma of germinal center origin,which presents with significant biologic and clinical heterogeneity. Using RNA-seq on B cells sorted from 87 FL biopsies,combined with machine-learning approaches,we identify 3 transcriptional states that divide the biological ontology of FL B cells into inflamed,proliferative,and chromatin-modifying states,with relationship to prior GC B cell phenotypes. When integrated with whole-exome sequencing and immune profiling,we find that each state was associated with a combination of mutations in chromatin modifiers,copy-number alterations to TNFAIP3,and T follicular helper cells (Tfh) cell interactions,or primarily by a microenvironment rich in activated T cells. Altogether,these data define FL B cell transcriptional states across a large cohort of patients,contribute to our understanding of FL heterogeneity at the tumor cell level,and provide a foundation for guiding therapeutic intervention. Graphical abstract Highlights•B cells from follicular lymphoma exhibit 3 distinct transcriptional states•FL B cells differ by enhanced inflammation,proliferation,or chromatin remodeling•Tumor cell states correlate with unique immune-microenvironment features•Unique mutation and CNV profiles highlight potential genetic causes of heterogeneity Krull et al. analyzed bulk transcriptional,genomic,and immune profiles of B cells from follicular lymphoma and reveal 3 distinct transcriptional states. These cell states underscore the inherent variability of FL tumors,independent of stroma,and implicate intrinsic differences as an underpinning to FL heterogeneity. View Publication

IntroductionBAP1 is a deubiquitinase (DUB) of the Ubiquitin C-terminal Hydrolase (UCH) family that regulates gene expression and other cellular processes,through its direct catalytic activity on the repressive epigenetic mark histone H2AK119ub,as well as on several other substrates. BAP1 is also a highly important tumor suppressor,expressed and functional across many cell types and tissues. In recent work,we demonstrated a cell intrinsic role of BAP1 in the B cell lineage development in murine bone marrow,however the role of BAP1 in the regulation of B cell mediated humoral immune response has not been previously explored. Methods and resultsIn the current study,we demonstrate that a B-cell intrinsic loss of BAP1 in activated B cells in the Bap1 fl/fl Cγ1-cre murine model results in a severe defect in antibody production,with altered dynamics of germinal centre B cell,memory B cell,and plasma cell numbers. At the cellular and molecular level,BAP1 was dispensable for B cell immunoglobulin class switching but resulted in an impaired proliferation of activated B cells,with genome-wide dysregulation in histone H2AK119ub levels and gene expression. Conclusion and discussionIn summary,our study establishes the B-cell intrinsic role of BAP1 in antibody mediated immune response and indicates its central role in the regulation of the genome-wide landscapes of histone H2AK119ub and downstream transcriptional programs of B cell activation and humoral immunity. View Publication