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1.
PLoS Pathog ; 20(1): e1011983, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38271477

RESUMO

The protein basic helix-loop-helix family member e40 (BHLHE40) is a transcription factor recently emerged as a key regulator of host immunity to infections, autoimmune diseases and cancer. In this study, we investigated the role of Bhlhe40 in protective T cell responses to the intracellular bacterium Chlamydia in the female reproductive tract (FRT). Mice deficient in Bhlhe40 exhibited severe defects in their ability to control Chlamydia muridarum shedding from the FRT. The heightened bacterial burdens in Bhlhe40-/- mice correlated with a marked increase in IL-10-producing T regulatory type 1 (Tr1) cells and decreased polyfunctional CD4 T cells co-producing IFN-γ, IL-17A and GM-CSF. Genetic ablation of IL-10 or functional blockade of IL-10R increased CD4 T cell polyfunctionality and partially rescued the defects in bacterial control in Bhlhe40-/- mice. Using single-cell RNA sequencing coupled with TCR profiling, we detected a significant enrichment of stem-like T cell signatures in Bhlhe40-deficient CD4 T cells, whereas WT CD4 T cells were further down on the differentiation trajectory with distinct effector functions beyond IFN-γ production by Th1 cells. Altogether, we identified Bhlhe40 as a key molecular driver of CD4 T cell differentiation and polyfunctional responses in the FRT against Chlamydia.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Linfócitos T CD4-Positivos , Infecções por Chlamydia , Chlamydia muridarum , Proteínas de Homeodomínio , Animais , Feminino , Camundongos , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular , Infecções por Chlamydia/imunologia , Chlamydia muridarum/fisiologia , Interleucina-10/metabolismo , Camundongos Endogâmicos C57BL , Células Th1/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Homeodomínio/metabolismo
2.
Circ Res ; 130(10): 1550-1564, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35430873

RESUMO

BACKGROUND: Renal T cells contribute importantly to hypertension, but the underlying mechanism is incompletely understood. We reported that CD8Ts directly stimulate distal convoluted tubule cells (DCTs) to increase NCC (sodium chloride co-transporter) expression and salt reabsorption. However, the mechanistic basis of this pathogenic pathway that promotes hypertension remains to be elucidated. METHODS: We used mouse models of DOCA+salt (DOCA) treatment and adoptive transfer of CD8+ T cells (CD8T) from hypertensive animals to normotensive animals in in vivo studies. Co-culture of mouse DCTs and CD8Ts was used as in vitro model to test the effect of CD8T activation in promoting NCC-mediated sodium retention and to identify critical molecular players contributing to the CD8T-DCT interaction. Interferon (IFNγ)-KO mice and mice receiving renal tubule-specific knockdown of PDL1 were used to verify in vitro findings. Blood pressure was continuously monitored via radio-biotelemetry, and kidney samples were saved at experimental end points for analysis. RESULTS: We identified critical molecular players and demonstrated their roles in augmenting the CD8T-DCT interaction leading to salt-sensitive hypertension. We found that activated CD8Ts exhibit enhanced interaction with DCTs via IFN-γ-induced upregulation of MHC-I and PDL1 in DCTs, thereby stimulating higher expression of NCC in DCTs to cause excessive salt retention and progressive elevation of blood pressure. Eliminating IFN-γ or renal tubule-specific knockdown of PDL1 prevented T cell homing into the kidney, thereby attenuating hypertension in 2 different mouse models. CONCLUSIONS: Our results identified the role of activated CD8Ts in contributing to increased sodium retention in DCTS through the IFNγ-PDL1 pathway. These findings provide a new mechanism for T cell involvement in the pathogenesis of hypertension and reveal novel therapeutic targets.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão , Animais , Linfócitos T CD8-Positivos/metabolismo , Acetato de Desoxicorticosterona/metabolismo , Acetato de Desoxicorticosterona/farmacologia , Modelos Animais de Doenças , Hipertensão/metabolismo , Túbulos Renais Distais/metabolismo , Túbulos Renais Distais/patologia , Camundongos , Sódio/metabolismo , Simportadores de Cloreto de Sódio/metabolismo , Cloreto de Sódio na Dieta
3.
Immunity ; 40(2): 213-24, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24508233

RESUMO

T cell effector functions can be elicited by noncognate stimuli, but the mechanism and contribution of this pathway to the resolution of intracellular macrophage infections have not been defined. Here, we show that CD4(+) T helper 1 (Th1) cells could be rapidly stimulated by microbe-associated molecular patterns during active infection with Salmonella or Chlamydia. Further, maximal stimulation of Th1 cells by lipopolysaccharide (LPS) did not require T-cell-intrinsic expression of toll-like receptor 4 (TLR4), interleukin-1 receptor (IL-1R), or interferon-γ receptor (IFN-γR) but instead required IL-18R, IL-33R, and adaptor protein MyD88. Innate stimulation of Th1 cells also required host expression of TLR4 and inflammasome components that together increased serum concentrations of IL-18. Finally, the elimination of noncognate Th1 cell stimulation hindered the resolution of primary Salmonella infection. Thus, the in vivo bactericidal capacity of Th1 cells is regulated by the response to noncognate stimuli elicited by multiple innate immune receptors.


Assuntos
Imunidade Inata/imunologia , Inflamassomos/metabolismo , Transdução de Sinais , Células Th1/imunologia , Receptores Toll-Like/metabolismo , Animais , Carga Bacteriana/imunologia , Antígenos CD4/imunologia , Chlamydia/fisiologia , Citometria de Fluxo , Interleucina-18/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , Salmonella/fisiologia , Receptor 4 Toll-Like/metabolismo
4.
Infect Immun ; 90(12): e0032822, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36374101

RESUMO

CD4 T cell-dependent IFNγ production and antibody are the two best known effectors for protective immunity against Chlamydia female reproductive tract (FRT) infection. Nevertheless, mice lacking either IFNγ or B cells can clear the vast majority of Chlamydia from the FRT, while suffering from varying degrees of disseminated infection. In this study, we investigated whether IFNγ and B cells play complementary roles in host defense against Chlamydia and evaluated their relative contributions in systemic and mucosal tissues. Using mice deficient in both IFNγ and B cells (IFNγ-/- x µMT), we showed that mice lacking both effectors were highly susceptible to lethal systemic bacterial dissemination following Chlamydia muridarum intravaginal infection. Passive transfer of immune convalescent serum, but not recombinant IFNγ, reduced bacterial burden in both systemic and mucosal tissues in IFNγ-/- x µMT mice. Notably, over the course of primary infection, we observed a reduction of bacterial shedding of more than 2 orders of magnitude in IFNγ-/- x µMT mice following both C. muridarum and C. trachomatis FRT infections. In contrast, no protective immunity against C. muridarum reinfection was detected in the absence of IFNγ and B cells. Together, our results suggest that IFNγ and B cells synergize to combat systemic Chlamydia dissemination, while additional IFNγ and B cell-independent mechanisms exist for host resistance to Chlamydia in the lower FRT.


Assuntos
Infecções por Chlamydia , Chlamydia muridarum , Infecções do Sistema Genital , Feminino , Camundongos , Animais , Reinfecção , Chlamydia trachomatis , Infecções por Chlamydia/microbiologia , Infecções do Sistema Genital/microbiologia , Interferon gama , Anticorpos Antibacterianos
5.
Infect Immun ; 89(3)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33257535

RESUMO

Protective immunity against the obligate intracellular bacterium Chlamydia has long been thought to rely on CD4 T cell-dependent gamma interferon (IFN-γ) production. Nevertheless, whether IFN-γ is produced by other cellular sources during Chlamydia infection and how CD4 T cell-dependent and -independent IFN-γ contribute differently to host resistance have not been carefully evaluated. In this study, we dissected the requirements of IFN-γ produced by innate immune cells and CD4 T cells for resolution of Chlamydia muridarum female reproductive tract (FRT) infection. After C. muridarum intravaginal infection, IFN-γ-deficient and T cell-deficient mice exhibited opposite phenotypes for survival and bacterial shedding at the FRT mucosa, demonstrating the distinct requirements for IFN-γ and CD4 T cells in host defense against Chlamydia In Rag1-deficient mice, IFN-γ produced by innate lymphocytes (ILCs) accounted for early bacterial control and prolonged survival in the absence of adaptive immunity. Although type I ILCs are potent IFN-γ producers, we found that mature NK cells and ILC1s were not the sole sources of innate IFN-γ in response to Chlamydia By conducting T cell adoptive transfer, we showed definitively that IFN-γ-deficient CD4 T cells were sufficient for effective bacterial killing in the FRT during the first 21 days of infection and reduced bacterial burden more than 1,000-fold, although mice receiving IFN-γ-deficient CD4 T cells failed to completely eradicate the bacteria from the FRT like their counterparts receiving wild-type (WT) CD4 T cells. Together, our results revealed that innate IFN-γ is essential for preventing systemic Chlamydia dissemination, whereas IFN-γ produced by CD4 T cells is largely redundant at the FRT mucosa.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Infecções por Chlamydia/imunologia , Genitália Feminina/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/genética , Interferon gama/imunologia , Camundongos Endogâmicos C57BL/imunologia , Infecções do Sistema Genital/imunologia , Animais , Chlamydia muridarum , Feminino , Humanos , Camundongos , Modelos Animais
6.
Eur J Immunol ; 50(5): 676-684, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32026472

RESUMO

The obligate intracellular bacterium Chlamydia trachomatis causes the most prevalent bacterial sexually transmitted infection worldwide. CD4 T cells play a central role in the protective immunity against Chlamydia female reproductive tract (FRT) infection, while B cells are thought to be dispensable for resolution of primary Chlamydia infection in mouse models. We recently reported an unexpected requirement of B cells in local Chlamydia-specific CD4 T-cell priming and bacterial containment within the FRT. Here, we sought to tackle the precise effector function of B cells during Chlamydia primary infection. Using mixed bone marrow chimeras that lack B-cell-dependent Ag presentation (MHCIIB-/- ) or devoid of circulating antibodies (AID-/- × µS-/- ), we show that Chlamydia-specific CD4 T-cell expansion does not rely on Ag presentation by B cells. Importantly, we demonstrate that antibody, but not B-cell-dependent Ag presentation, is required for preventing systemic bacterial dissemination following Chlamydia FRT infection.


Assuntos
Anticorpos Antibacterianos/biossíntese , Linfócitos B/imunologia , Bacteriemia/imunologia , Células da Medula Óssea/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por Chlamydia/imunologia , Chlamydia trachomatis/imunologia , Animais , Apresentação de Antígeno , Linfócitos B/microbiologia , Bacteriemia/microbiologia , Bacteriemia/patologia , Células da Medula Óssea/microbiologia , Linfócitos T CD4-Positivos/microbiologia , Infecções por Chlamydia/microbiologia , Infecções por Chlamydia/patologia , Chlamydia trachomatis/crescimento & desenvolvimento , Chlamydia trachomatis/patogenicidade , Modelos Animais de Doenças , Feminino , Imunidade Humoral , Isotipos de Imunoglobulinas , Camundongos , Quimeras de Transplante , Vagina/imunologia , Vagina/microbiologia , Irradiação Corporal Total
7.
J Immunol ; 199(7): 2547-2554, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28801359

RESUMO

Immune mechanisms responsible for pathogen clearance from the female reproductive tract (FRT) are incompletely defined; in particular, the contribution of lymphocyte trafficking to this process is unclear. CCR7-deficient mice have profoundly altered lymphocyte recirculation and display ectopic formation of lymphocyte aggregates within mucosal nonlymphoid tissues, including the FRT. In this study, we investigated how altered lymphocyte distribution in CCR7-deficient mice would affect host responses to Chlamydia muridarum within the reproductive tract. As expected, CCR7-deficient mice exhibited reduced lymphocyte trafficking to lymph nodes and a corresponding increase in T cell populations within the FRT. After intravaginal infection with Chlamydia, CCR7-deficient mice displayed markedly reduced Ag-specific CD4 T cell responses within the local draining iliac lymph nodes, yet robust Th1 and Th17 responses were prominent in the FRT. In addition, Chlamydia-specific Ab responses were dysregulated in CCR7-deficient mice, displaying an unexpected increase in the systemic IgA responses. Importantly, prominent mucosal immune responses in CCR7-deficient mice increased the efficiency of bacteria clearance from the FRT while reducing tissue-associated inflammation and pathology. Thus, increased numbers of lymphocytes within the FRT result in pathogen clearance with reduced immune-mediated pathology.


Assuntos
Infecções por Chlamydia/imunologia , Infecções por Chlamydia/microbiologia , Chlamydia muridarum/imunologia , Receptores CCR7/imunologia , Infecções do Sistema Genital/imunologia , Infecções do Sistema Genital/microbiologia , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/sangue , Linfócitos T CD4-Positivos/imunologia , Movimento Celular , Chlamydia muridarum/isolamento & purificação , Feminino , Imunoglobulina A/sangue , Inflamação/microbiologia , Linfonodos/imunologia , Camundongos , Camundongos Knockout , Receptores CCR7/deficiência , Receptores CCR7/genética , Células Th1/imunologia , Células Th17/imunologia
8.
Infect Immun ; 84(10): 2833-41, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27456828

RESUMO

Salmonella infection profoundly affects host erythroid development, but the mechanisms responsible for this effect remain poorly understood. We monitored the impact of Salmonella infection on erythroid development and found that systemic infection induced anemia, splenomegaly, elevated erythropoietin (EPO) levels, and extramedullary erythropoiesis in a process independent of Salmonella pathogenicity island 2 (SPI2) or flagellin. The circulating EPO level was also constitutively higher in mice lacking the expression of signal-regulatory protein α (SIRPα). The expression level of EPO mRNA was elevated in the kidney and liver but not increased in the spleens of infected mice despite the presence of extramedullary erythropoiesis in this tissue. In contrast to data from a previous report, mice lacking EPO receptor (EPOR) expression on nonerythroid cells (EPOR rescued) had bacterial loads similar to those of wild-type mice following Salmonella infection. Indeed, treatment to reduce splenic erythroblasts and mature red blood cells correlated with elevated bacterial burdens, implying that extramedullary erythropoiesis benefits the host. Together, these findings emphasize the profound effect of Salmonella infection on erythroid development and suggest that the modulation of erythroid development has both positive and negative consequences for host immunity.


Assuntos
Eritropoetina/metabolismo , Rim/metabolismo , Fígado/metabolismo , Infecções por Salmonella/metabolismo , Infecções por Salmonella/microbiologia , Salmonella typhi , Anemia/sangue , Animais , Carga Bacteriana , Modelos Animais de Doenças , Eritropoese/fisiologia , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Receptores da Eritropoetina/metabolismo , Receptores Imunológicos/metabolismo , Baço/metabolismo
9.
Eur J Immunol ; 45(2): 513-24, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25430631

RESUMO

Toll-like receptors (TLRs) can recognize microbial patterns and utilize adaptor molecules, such as-MyD88 or (TRIF TIR-domain-containing adapter-inducing interferon-ß), to initiate downstream signaling that ultimately affects the initiation of adaptive immunity. In addition to this inflammatory role, TLR5 expression on dendritic cells can favor antigen presentation of flagellin peptides and thus increase the sensitivity of flagellin-specific T-cell responses in vitro and in vivo. Here, we examined the role of alternative signaling pathways that might regulate flagellin antigen presentation in addition to MyD88. These studies suggest a requirement for spleen tyrosine kinase, a noncanonical TLR-signaling adaptor molecule, and its downstream molecule CARD9 in regulating the sensitivity of flagellin-specific CD4(+) T-cell responses in vitro and in vivo. Thus, a previously unappreciated signaling pathway plays an important role in regulating the dominance of flagellin-specific T-cell responses.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/genética , Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Flagelina/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Tirosina Quinases/genética , Transdução de Sinais/imunologia , Imunidade Adaptativa , Animais , Apresentação de Antígeno , Proteínas Adaptadoras de Sinalização CARD/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Comunicação Celular , Proliferação de Células , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Flagelina/imunologia , Regulação da Expressão Gênica , Imunidade Inata , Interleucina-2/genética , Interleucina-2/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Lisossomos/imunologia , Lisossomos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/deficiência , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Fagossomos/imunologia , Fagossomos/metabolismo , Proteínas Tirosina Quinases/imunologia , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/imunologia , Quinase Syk , Receptor 5 Toll-Like/genética , Receptor 5 Toll-Like/imunologia
10.
PLoS Pathog ; 9(10): e1003707, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24204262

RESUMO

B cells can contribute to acquired immunity against intracellular bacteria, but do not usually participate in primary clearance. Here, we examined the endogenous CD4 T cell response to genital infection with Chlamydia muridarum using MHC class-II tetramers. Chlamydia-specific CD4 T cells expanded rapidly and persisted as a stable memory pool for several months after infection. While most lymph node Chlamydia-specific CD4 T cells expressed T-bet, a small percentage co-expressed Foxp3, and RORγt-expressing T cells were enriched within the reproductive tract. Local Chlamydia-specific CD4 T cell priming was markedly reduced in mice lacking B cells, and bacteria were able to disseminate to the peritoneal cavity, initiating a cellular infiltrate and ascites. However, bacterial dissemination also coincided with elevated systemic Chlamydia-specific CD4 T cell responses and resolution of primary infection. Together, these data reveal heterogeneity in pathogen-specific CD4 T cell responses within the genital tract and an unexpected requirement for B cells in regulating local T cell activation and bacterial dissemination during genital infection.


Assuntos
Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por Chlamydia/imunologia , Chlamydia muridarum/imunologia , Imunidade Celular , Infecções do Sistema Genital/imunologia , Animais , Linfócitos T CD4-Positivos/patologia , Infecções por Chlamydia/patologia , Feminino , Fatores de Transcrição Forkhead/imunologia , Células HeLa , Humanos , Masculino , Camundongos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Infecções do Sistema Genital/microbiologia , Infecções do Sistema Genital/patologia
11.
J Immunol ; 189(5): 2537-44, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22851710

RESUMO

Recent studies have shed light on the connection between elevated erythropoetin production/spleen erythropoiesis and increased susceptibility to Salmonella infection. In this article, we provide another mouse model, the SIRPα-deficient (Sirpα⁻/⁻) mouse, that manifests increased erythropoiesis as well as heightened susceptibility to Salmonella infection. Sirpα⁻/⁻ mice succumbed to systemic infection with attenuated Salmonella, possessing significantly higher bacterial loads in both the spleen and the liver. Moreover, Salmonella-specific Ab production and Ag-specific CD4 T cells were reduced in Sirpα⁻/⁻ mice compared with wild-type controls. To further characterize the potential mechanism underlying SIRPα-dependent Ag-specific CD4 T cell priming, we demonstrate that lack of SIRPα expression on dendritic cells results in less efficient Ag processing and presentation in vitro. Collectively, these findings demonstrate an indispensable role of SIRPα for protective immunity to Salmonella infection.


Assuntos
Predisposição Genética para Doença , Receptores Imunológicos/deficiência , Infecções por Salmonella/imunologia , Regulação para Cima/imunologia , Animais , Infecções por Chlamydia/genética , Infecções por Chlamydia/imunologia , Infecções por Chlamydia/patologia , Chlamydia muridarum/imunologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptores Imunológicos/genética , Infecções por Salmonella/genética , Infecções por Salmonella/patologia , Salmonella typhimurium/imunologia , Regulação para Cima/genética
12.
Hypertension ; 81(3): 530-540, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38193292

RESUMO

BACKGROUND: CD8+ T cells (CD8Ts) have been implicated in hypertension. However, the specific mechanisms are not fully understood. In this study, we explore the contribution of the P2X7 (purinergic receptor P2X7) receptor to CD8T activation and subsequent promotion of sodium retention in the kidney. METHODS: We used mouse models of hypertension. Wild type were used as genetic controls, OT1 and Rag2/OT1 mice were utilized to determine antigen dependency, and P2X7-knockout mice were studied to define the role of P2X7 in activating CD8Ts and promoting hypertension. Blood pressure was monitored continuously and kidneys were obtained at different experimental end points. Freshly isolated CD8Ts from mice for activation assays and ATP stimulation. CD8T activation-induced promotion of sodium retention was explored in cocultures of CD8Ts and mouse DCTs. RESULTS: We found that OT1 and Rag2/OT1 mice, which are nonresponsive to common antigens, still developed hypertension and CD8T-activation in response to deoxycorticosterone acetate/salt treatment, similar to wild-type mice. Further studies identified the P2X7 receptor on CD8Ts as a possible mediator of this antigen-independent activation of CD8Ts in hypertension. Knockout of the P2X7 receptor prevented calcium influx and cytokine production in CD8Ts. This finding was associated with reduced CD8T-DCT stimulation, reversal of excessive salt retention in DCTs, and attenuated development of salt-sensitive hypertension. CONCLUSIONS: Our findings suggest a novel mechanism by which CD8Ts are activated in hypertension to exacerbate salt retention and infer that the P2X7 receptor on CD8Ts may represent a new therapeutic target to attenuate T-cell-mediated immunopathology in hypertension.


Assuntos
Linfócitos T CD8-Positivos , Hipertensão , Animais , Camundongos , Trifosfato de Adenosina , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Purinérgicos P2X7/metabolismo , Sódio , Cloreto de Sódio na Dieta
13.
Mucosal Immunol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38844208

RESUMO

Mycobacterium tuberculosis (Mtb)-infected neutrophils are often found in the airways of patients with active tuberculosis (TB), and excessive recruitment of neutrophils to the lung is linked to increased bacterial burden and aggravated pathology in TB. The basis for the permissiveness of neutrophils for Mtb and the ability to be pathogenic in TB has been elusive. Here, we identified metabolic and functional features of neutrophils that contribute to their permissiveness in Mtb infection. Using single-cell metabolic and transcriptional analyses, we found that neutrophils in the Mtb-infected lung displayed elevated mitochondrial metabolism, which was largely attributed to the induction of activated neutrophils with enhanced metabolic activities. The activated neutrophil subpopulation was also identified in the lung granulomas from Mtb-infected non-human primates. Functionally, activated neutrophils harbored more viable bacteria and displayed enhanced lipid uptake and accumulation. Surprisingly, we found that interferon-γ promoted the activation of lung neutrophils during Mtb infection. Lastly, perturbation of lipid uptake pathways selectively compromised Mtb survival in activated neutrophils. These findings suggest that neutrophil heterogeneity and metabolic diversity are key to their permissiveness for Mtb and that metabolic pathways in neutrophils represent potential host-directed therapeutics in TB.

14.
Zhongguo Zhong Yao Za Zhi ; 38(11): 1827-31, 2013 Jun.
Artigo em Zh | MEDLINE | ID: mdl-24010305

RESUMO

To observe the clinical effect of Jianpi Bushen formula to prevent the collapse of osteonecrosis of femoral head (ONFH) of type phlegm and blood stasis obstructing the collaterals. 50 cases (including 73 hips) of non-collapse ONFH (ARCO I, II, III a) were selected from the out-patient department of orthopedic in Guang'anmen Hospital attached to China Academy of Chinese Medical Science. All the cases fit for diagnostic criteria were given Jianpi Bushen formula and followed up. Staging criteria was ARCO classification. Harris score evaluated the hip function. The mean follow-up time was 4.2 years (3-5.4 years). After a mean of 4.2 years (3-5.4 years) followed-up, 12 hips collapse occurred while 61 hips not (the non-collapse rate was 83.56%). Collapse did not occurred among the all 7 hips at stage ARCO I (the non-collapse rate was 100%). Among the 49 hips at stage ARCO II, 9 hips collapse occurred while 40 hips not (the non-collapse rate was 81.63%). Among the 17 hips at stage ARCO III a, 3 hips collapse occurred while 14 hips not (the non-collapse rate was 82.35%). Kaplan-Meier analysis showed the average survival time of non-collapse was 5 years (4. 8-5.2 years). The 3 year survival rate of non-collapse was 92.5%. The 4 year survival rate was 74% and the condition tended to be stability trend. The Harris score was 71.93 +/- 11.25 before treatment and 81.63 +/- 12.16 after treatment, significantly different. These results suggest that: Jianpi Bushen formula is an effective method for treating ONFH of type phlegm and blood stasis obstructing the collaterals. It can delay or prevent the collapse of femoral head and significantly improve the hip function.


Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , Necrose da Cabeça do Fêmur/tratamento farmacológico , Adulto , Idoso , Feminino , Necrose da Cabeça do Fêmur/prevenção & controle , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
15.
bioRxiv ; 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37961221

RESUMO

The protein basic helix-loop-helix family member e40 (BHLHE40) is a transcription factor recently emerged as a key regulator of host immunity to infections, autoimmune diseases and cancer. In this study, we investigated the role of Bhlhe40 in protective T cell responses to the intracellular bacterium Chlamydia in the female reproductive tract (FRT). Mice deficient in Bhlhe40 exhibited severe defects in their ability to control Chlamydia muridarum shedding from the FRT. The heightened bacterial burdens in Bhlhe40-/- mice correlated with a marked increase in IL-10-producing T regulatory type 1 (Tr1) cells and decreased polyfunctional CD4 T cells co-producing IFN-γ, IL-17A and GM-CSF. Genetic ablation of IL-10 or functional blockade of IL-10R increased CD4 T cell polyfunctionality and partially rescued the defects in bacterial control in Bhlhe40-/- mice. Using single-cell RNA sequencing coupled with TCR profiling, we detected a significant enrichment of stem-like T cell signatures in Bhlhe40-deficient CD4 T cells, whereas WT CD4 T cells were further down on the differentiation trajectory with distinct effector functions beyond IFN-γ production by Th1 cells. Altogether, we identified Bhlhe40 as a key molecular driver of CD4 T cell differentiation and polyfunctional responses in the FRT against Chlamydia.

16.
J Immunol ; 184(4): 1728-36, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20065110

RESUMO

Ras plays an important role in B cell development. However, the stage at which Ras governs B cell development remains unclear. Moreover, the upstream receptors and downstream effectors of Ras that govern B cell differentiation remain undefined. Using mice that express a dominant-negative form of Ras, we demonstrate that Ras-mediated signaling plays a critical role in the development of common lymphoid progenitors. This developmental block parallels that found in flt3(-/-) mice, suggesting that Flt3 is an important upstream activator of Ras in early B cell progenitors. Ras inhibition impaired proliferation of common lymphoid progenitors and pre-pro-B cells but not pro-B cells. Rather, Ras promotes STAT5-dependent pro-B cell differentiation by enhancing IL-7Ralpha levels and suppressing socs2 and socs3 expression. Our results suggest a model in which Flt3/Ras-dependent signals play a critical role in B cell development by priming early B cell progenitors for subsequent STAT5-dependent B cell differentiation.


Assuntos
Linfócitos B/imunologia , Diferenciação Celular/imunologia , Interleucina-7/fisiologia , Transdução de Sinais/imunologia , Tirosina Quinase 3 Semelhante a fms/fisiologia , Proteínas ras/fisiologia , Animais , Linfócitos B/citologia , Linfócitos B/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Técnicas de Introdução de Genes , Humanos , Células Progenitoras Linfoides/citologia , Células Progenitoras Linfoides/imunologia , Células Progenitoras Linfoides/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Camundongos Transgênicos , Fator de Transcrição STAT5/fisiologia , Transdução de Sinais/genética , Tirosina Quinase 3 Semelhante a fms/deficiência , Tirosina Quinase 3 Semelhante a fms/genética , Proteínas ras/genética
17.
J Immunol ; 184(8): 4074-7, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20228198

RESUMO

Regulatory T cell (Treg) development proceeds via a two-step process in which naive CD4(+) thymocytes are first converted into CD4(+)CD25(+)CD122(+)GITR(+)Foxp3(-) Treg progenitors, followed by a second step in which IL-2 converts these Treg progenitors into CD4(+)Foxp3(+) Tregs. The costimulatory molecule CD28 is required for efficient Treg development. However, the stage at which CD28 affects Treg development remains undefined. In this article, we demonstrate that Cd28(-/-) mice lack Treg progenitors. Furthermore, the P(187)YAP motif in the cytoplasmic tail of CD28, which links CD28 to Lck activation, is required for this process. In contrast, the Y(170)MNM motif, which links CD28 to PI3K activation, is not required for Treg progenitor development. Finally, the CD28/Lck pathway was shown to activate the NF-kappaB family of transcription factors. We demonstrate that c-Rel, but not NF-kappaB1, promotes the development of Treg progenitors. Thus, a CD28/c-Rel-dependent pathway is involved in initiating Treg development.


Assuntos
Antígenos CD28/fisiologia , Diferenciação Celular/imunologia , Proteínas Proto-Oncogênicas c-rel/fisiologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Motivos de Aminoácidos/genética , Motivos de Aminoácidos/imunologia , Animais , Antígenos CD28/biossíntese , Antígenos CD28/genética , Diferenciação Celular/genética , Citoplasma/enzimologia , Citoplasma/genética , Citoplasma/imunologia , Ativação Enzimática/genética , Ativação Enzimática/imunologia , Regulação da Expressão Gênica/imunologia , Técnicas de Introdução de Genes , Interleucina-2/biossíntese , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/genética , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Camundongos Transgênicos , NF-kappa B/metabolismo , Subunidade p50 de NF-kappa B/deficiência , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/fisiologia , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/fisiologia , Ligação Proteica/genética , Ligação Proteica/imunologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Células-Tronco/imunologia , Células-Tronco/metabolismo , Células-Tronco/patologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia
18.
Infect Immun ; 79(4): 1479-88, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21263018

RESUMO

Enteric pathogens can cause relapsing infections in a proportion of treated patients, but greater understanding of this phenomenon is hindered by the lack of appropriate animal models. We report here a robust animal model of relapsing primary typhoid that initiates after apparently successful antibiotic treatment of susceptible mice. Four days of enrofloxacin treatment were sufficient to reduce bacterial loads below detectable levels in all major organs, and mice appeared otherwise healthy. However, any interruption of further antibiotic therapy allowed renewed fecal shedding and renewed bacterial growth in systemic tissues to occur, and mice eventually succumbed to relapsing infection. In vivo imaging of luminescent Salmonella identified the mesenteric lymph nodes (MLNs) as a major reservoir of relapsing infection. A magnetic-bead enrichment strategy isolated MLN-resident CD11b(+) Gr-1(-) monocytes associated with low numbers of persistent Salmonella. However, the removal of MLNs increased the severity of typhoid relapse, demonstrating that this organ serves as a protective filter to restrain the dissemination of bacteria during antibiotic therapy. Together, these data describe a robust animal model of typhoid relapse and identify an important intestinal phagocyte subset involved in protection against the systemic spread of enteric infection.


Assuntos
Linfonodos/microbiologia , Monócitos/microbiologia , Salmonelose Animal/microbiologia , Animais , Antibacterianos/uso terapêutico , Separação Celular , Modelos Animais de Doenças , Enrofloxacina , Citometria de Fluxo , Fluoroquinolonas/uso terapêutico , Intestino Delgado/microbiologia , Mesentério/imunologia , Mesentério/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/imunologia , Recidiva , Salmonelose Animal/imunologia , Salmonelose Animal/patologia , Salmonella typhi/imunologia
19.
J Mol Endocrinol ; 67(4): 173-188, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34382943

RESUMO

Epidemiological studies inversely associate BMI with breast cancer risk in premenopausal women, but the pathophysiological linkage remains ill-defined. Despite the documented relevance of the 'local' environment to breast cancer progression and the well-accepted differences in transcriptome and metabolic properties of anatomically distinct fat depots, specific breast adipose contributions to the proliferative potential of non-diseased breast glandular compartment are not fully understood. To address early breast cancer causation in the context of obesity status, we compared the cellular and molecular phenotypes of breast adipose and matched breast glandular tissue from premenopausal non-obese (mean BMI = 27 kg/m2) and obese (mean BMI = 44 kg/m2) women. Breast adipose from obese women showed higher expression levels of adipogenic, pro-inflammatory, and estrogen synthetic genes than from non-obese women. Obese breast glandular tissue displayed lower proliferation and inflammatory status and higher expression of anti-proliferative/pro-senescence biomarkers TP53 and p21 than from non-obese women. Transcript levels for T-cell receptor and co-receptors CD3 and CD4 were higher in breast adipose of obese cohorts, coincident with elevated adipose interleukin 10 (IL10) and FOXP3 gene expression. In human breast epithelial cell lines MCF10A and HMEC, recombinant human IL10 reduced cell viability and CCND1 transcript levels, increased those of TP53 and p21, and promoted (MCF10A) apoptosis. Our findings suggest that breast adipose-associated IL10 may mediate paracrine interactions between non-diseased breast adipose and breast glandular compartments and highlight how breast adipose may program the local inflammatory milieu, partly by recruiting FOXP3+ T regulatory cells, to influence premenopausal breast cancer risk.


Assuntos
Tecido Adiposo/metabolismo , Mama/metabolismo , Epitélio/metabolismo , Interleucina-10/metabolismo , Fenótipo , Pré-Menopausa/metabolismo , Adipócitos/imunologia , Adipócitos/metabolismo , Adiposidade , Adulto , Biomarcadores , Mama/patologia , Neoplasias da Mama/etiologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Citocinas/genética , Citocinas/metabolismo , Feminino , Expressão Gênica , Hormônios Esteroides Gonadais/sangue , Hormônios Esteroides Gonadais/metabolismo , Humanos , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Pessoa de Meia-Idade , Modelos Biológicos , Obesidade/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Telômero/genética , Telômero/metabolismo , Adulto Jovem
20.
Open Med (Wars) ; 15: 152-159, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190739

RESUMO

BACKGROUND: There is a controversial relationship between the negative lymph nodes (NLNs) and survival in patients with esophageal squamous cell carcinoma (ESCC). This study investigates the implications of total number of NLNs on thoracic ESCC patient prognosis. METHODS: 579 thoracic ESCC patients were categorized into four groups (0-9, 10-14, 15-19 and ≥20 NLNs). Univariate analysis was done by the log-rank tests while multivariate analysis was undertaken using Cox regression models. Survival analysis was determined employing the Kaplan-Meier method. RESULTS: When the numbers of NLNs were 9 or less, 10 to 14, 15 to 19 and 20 or more, patients of 3-year survival rates were 21.7%, 40.0%, 61.2% and 77.5%, respectively (P<0.001). In the node-negative and node-positive subgroups, 3-year survival rates were 34.9% and 14.3%, 50.9% and 19.3%, 65.6% and 51.8%, 81.4% and 68.9% respectively (P<0.001). Gender, tumor length, tumor differentiation, T and N stage as well as the total NLNs were found to be significantly linked to survival rates. Multivariate analysis showed tumor length, T stage, N stage and total NLNs were independent prognostic factors for ESCC patients. CONCLUSION: NLNs numbers is a significant independent prognostic indicator for thoracic ESCC patients' survival after curative esophagectomy.

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