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1.
Immunology ; 159(1): 88-95, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606902

RESUMO

Severe sepsis is often accompanied by a transient immune paralysis, which is associated with enhanced susceptibility to secondary infections and poor clinical outcomes. The functional impairment of antigen-presenting cells is considered to be a major hallmark of this septic immunosuppression, with reduced HLA-DR expression on circulating monocytes serving as predictor of mortality. Unconventional lymphocytes like γδ T-cells have the potential to restore immune defects in a variety of pathologies including cancer, but their use to rescue sepsis-induced immunosuppression has not been investigated. Our own previous work showed that Vγ9/Vδ2+ γδ T-cells are potent activators of monocytes from healthy volunteers in vitro, and in individuals with osteoporosis after first-time administration of the anti-bone resorption drug zoledronate in vivo. We show here that zoledronate readily induces upregulation of HLA-DR, CD40 and CD64 on monocytes from both healthy controls and sepsis patients, which could be abrogated by neutralising the pro-inflammatory cytokines interferon (IFN)-γ and tumour necrosis factor (TNF)-α in the cultures. In healthy controls, the upregulation of HLA-DR on monocytes was proportional to the baseline percentage of Vγ9/Vδ2 T-cells in the peripheral blood mononuclear cell population. Of note, a proportion of sepsis patients studied here did not show a demonstrable response to zoledronate, predominantly patients with microbiologically confirmed bloodstream infections, compared with sepsis patients with more localised infections marked by negative blood cultures. Taken together, our results suggest that zoledronate can, at least in some individuals, rescue immunosuppressed monocytes during acute sepsis and thus may help improve clinical outcomes during severe infection.


Assuntos
Antígenos HLA-DR/imunologia , Fatores Imunológicos/farmacologia , Monócitos/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Sepse/tratamento farmacológico , Linfócitos T/efeitos dos fármacos , Ácido Zoledrônico/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Antígenos HLA-DR/metabolismo , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Sepse/sangue , Sepse/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
2.
Vet Clin North Am Food Anim Pract ; 35(3): 453-469, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31590897

RESUMO

Gamma delta (γδ) T cells constitute a major lymphocyte population in peripheral blood and epithelial surfaces. They play nonredundant roles in host defense against diverse pathogens. Although γδ T cells share functional features with other cells of the immune system, their distinct methods of antigen recognition, rapid response, and tissue tropism make them a unique effector population. This review considers the current state of our knowledge on γδ T cell biology in ruminants and the important roles played by this nonconventional T cell population in protection against several infectious diseases of veterinary and zoonotic importance.


Assuntos
Linfócitos Intraepiteliais/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Ruminantes/imunologia , Animais , Bovinos , Ovinos
3.
Exp Parasitol ; 204: 107725, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31306646

RESUMO

Characterisation of the cellular immune response to schistosomiasis is well established for Schistosoma mansoni but a comprehensive description of T cell-mediated immune responses against S. japonicum infection is lacking. Accordingly, 20 CBA mice were infected with cercariae of S. japonicum and the immune response at different time points was determined. Mouse spleen and liver lymphocytes were isolated from the mice and stimulated with schistosomal adult worm antigen preparation (SWAP) and schistosomal soluble egg antigen (SEA). There was a relatively higher Th1 immune response to SWAP compared to SEA at the early phase of infection (up to week 5 post challenge). However, a Th2 immune response directed against SEA was dominant at week 6 post-infection, a time point when the highest IgG response against both SWAP and, especially, SEA was generated. The regulatory immune response was highest at the early phase of the immune response (up to week 5 post challenge) followed by a rapid decline at week 6-post infection. Before egg-laying, S. japonicum induced a regulatory T cell immune response which may limit the early Th1-mediated immune response that is believed to be protective in murine schistosomiasis. Following egg laying, the immune response was polarized to a Th2 immune response mainly directed against the eggs and this may contribute to parasite survival.


Assuntos
Imunidade Celular , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Linfócitos T/imunologia , Animais , Antígenos de Helmintos/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Interleucina-17/imunologia , Interleucina-17/metabolismo , Fígado/citologia , Fígado/imunologia , Fígado/parasitologia , Linfócitos/imunologia , Camundongos , Camundongos Endogâmicos CBA , Óvulo/imunologia , Contagem de Ovos de Parasitas , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Caramujos/parasitologia , Baço/citologia , Baço/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th2/imunologia
4.
Indian J Pathol Microbiol ; 62(3): 399-404, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31361227

RESUMO

Background: It is hypothesized that the duodenal mucosal damage in patients with celiac disease (CeD) is caused by the mucosa-infiltrating lymphoid cells. This study aimed to analyze the immune effective and regulatory T (Treg) cells in duodenal biopsies from treatment-naive adult patients with CeD having different histological grades and controls. Patients and Methods: Dual-color immunohistochemical staining was done in a total of 234 duodenal biopsies, including 132 controls and 102 adult patients with CeD using CD20, CD3:CD4, CD3:CD8, CD4:FoxP3, CD8:FoxP3, and TCRαß:TCRγδ antibodies. The density of these lymphoid cells in lamina propria and mucosal epithelium was compared between controls and CeD, with different modified Marsh grades. Results: Densities of CD4+ T cells in lamina propria and CD8+γδ intraepithelial lymphocytes (IELs) were significantly more in biopsies from patients with CeD, than in controls. An increasing linear pattern of IELs, CD3+ T cells, and CD20+ B cells was observed with increasing grades of villous abnormalities. Although CD8+ FoxP3+ Treg cells were significantly more in biopsies from patients with CeD, there was no significant difference in CD4+ FoxP3+ Treg cell infiltrate between both the groups. Conclusion: Our finding in this observational study generates interest to study the local intestinal mucosal immunity in CeD in detail. A study to prove the failure of CD4+ FoxP3+ Treg cell recruitment in CeD and its direct functional impact may yield valuable information regarding loss of mucosal tolerance.


Assuntos
Doença Celíaca/classificação , Doença Celíaca/imunologia , Duodeno/imunologia , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Adolescente , Adulto , Biópsia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Estudos Transversais , Duodeno/citologia , Duodeno/patologia , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Mucosa Intestinal/patologia , Masculino , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T Reguladores/imunologia , Adulto Jovem
5.
PLoS One ; 14(5): e0216815, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31071196

RESUMO

Using induced pluripotent stem cells (iPSCs) to derive chimeric antigen receptor-modified T (CAR-T) cells has great industrial potential. A previous study used αß T cell-derived CAR-modified iPSCs to produce CAR-T cells. However, these αß T cells are restricted to autologous use and only recognize single cancer antigen. To make CAR-T alternative for allogeneic use, we reprogrammed γδ T cell into iPSCs (γδ T-iPSCs) to circumvent the risk of graft-versus-host disease. To target multiple cancer-associated antigens, we used an "NK cell-promoting" protocol to differentiate γδ T-iPSCs and to induce expression of natural killer receptors (NKRs). Through such two-step strategy, mimetic γδ T cells endowed with an array of NKRs and thus designated as "γδ natural killer T (γδ NKT) cells" were derived. With no/low-level expression of inhibitory killer cell immunoglobulin-like receptors (KIRs) and immune checkpoint receptors, γδ NKT cells may provide a potent "off-the-shelf" cytotoxic cell source to recognize multiple ubiquitous antigens in a broad spectrum of cancers.


Assuntos
Antígenos de Neoplasias/imunologia , Células-Tronco Pluripotentes Induzidas/imunologia , Células T Matadoras Naturais/imunologia , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos Quiméricos/imunologia , Antígenos de Neoplasias/genética , Células HCT116 , Células Hep G2 , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Células K562 , Células MCF-7 , Células T Matadoras Naturais/patologia , Neoplasias/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos Quiméricos/genética , Células THP-1
6.
Life Sci Alliance ; 2(3)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064767

RESUMO

There are seven Vγ gene segments in the TCR γ chain loci of mice. We developed monoclonal antibodies (mAbs) specific to the Vγ6 chain (Heilig & Tonegawa nomenclature). By immunizing Vγ4/6 KO mice with complementarity-determining region peptides in Vγ6 chains, we generated three hybridomas. These hybridomas produced mAbs capable of cell surface staining of Vγ6/Vδ1 gene-transfected T-cell line lacking TCR as well as of Vγ1- Vγ4- Vγ5- Vγ7- γδ T cells and the CD3high TCRδint γδ T cells in various organs. The location of Vγ6+ γδ T cells, which peaked in the newborn thymus, was associated with mTEC. In vivo administration of clone 1C10-1F7 mAb impaired protection against Klebsiella pneumoniae infection but ameliorated psoriasis-like dermatitis induced by imiquimod treatment. These new mAbs are useful to elucidate the development, location, and functions of Vγ6 γδ T cells in mice.


Assuntos
Anticorpos Monoclonais/farmacologia , Especificidade de Anticorpos , Receptores de Antígenos de Linfócitos T gama-delta/antagonistas & inibidores , Animais , Anticorpos Monoclonais/imunologia , Formação de Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Linhagem Celular Tumoral , Feminino , Imunização , Imunofenotipagem , Camundongos , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo
7.
Int Immunopharmacol ; 73: 172-180, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31100712

RESUMO

BACKGROUND: Although γδ T cells have been reported to be closely related to the immunopathogenesis of some viral infectious diseases, the changes or roles of γδ T cells in the development of hand, foot, and mouth disease (HFMD) remain unclear. METHODS: Peripheral γδ T cells and their subsets were determined by surface (γδ TCR, Vδ1 TCR, Vδ2 TCR, CD45RA, and CD27) or intracellular (IFN-γ, TNF-α, CD107a, and Granzyme B) markers in healthy controls (HCs) and HFMD patients with FACS. The plasma levels of IFN-γ, TNF-α, IL-6, and MCP-1 were measured by ELISA. Differences in γδ T cells or their subsets and correlations between γδ T cells and inflammation indicators were statistically analyzed. RESULTS: Compared to HCs, HFMD patients showed increased effector γδ T and TNF-α+γδ T cells and plasma TNF-α levels, especially in severe cases. In addition, significantly increased Vδ1 T and IFN-γ+γδ T cells and other plasma inflammatory cytokines were further found in severe patients. Furthermore, EV71+ severe patients showed significantly increased effector and cytokine-producing γδ T cells, while the EV71- severe patients displayed significantly greater plasma cytokine levels. The percentage of IFN-γ+γδ T or TNF-α+γδ T cells was positively correlated with that of effector γδ T cells. There was a positive correlation between the proportion of Vδ1 T cells and white blood cell (WBC) count or the proportion of IFN-γ+γδ T or TNF-α+γδ T cells and neutrophil (N) count, while there was a negative correlation between Vδ2 T cells and WBC or N count. Moreover, the percentages of Vδ1 T and effector γδ T cells in the acute phase of disease declined significantly to normal levels during the recovery phase. CONCLUSIONS: Increased effector γδ T cells with enhanced cytokine production were remarkably observed in severe HFMD patients, which was also associated with clinical inflammation parameters. These data indicated that γδ T cells might be involved in inflammatory abnormalities in severe HFMD.


Assuntos
Citocinas/imunologia , Doença de Mão, Pé e Boca/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Pré-Escolar , Feminino , Doença de Mão, Pé e Boca/virologia , Herpesvirus Humano 4/genética , Humanos , Lactente , Masculino , RNA Viral
8.
PLoS Pathog ; 15(4): e1007715, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30998783

RESUMO

Hepatitis B virus (HBV) persists with global and virus-specific T-cell dysfunction, without T-cell based correlates of outcomes. To determine if γδT-cells are altered in HBV infection relative to clinical status, we examined the frequency, phenotype and function of peripheral blood Vδ1+ and Vδ2+γδT-cells by multi-parameter cytometry in a clinically diverse North American cohort of chronic hepatitis B (CHB), acute hepatitis B (AHB) and uninfected control subjects. We show that circulating γδT-cells were comprised predominantly of CD3hiCD4- Vδ2+γδT-cells with frequencies that were 2-3 fold higher among Asian than non-Asian Americans and inversely correlated with age, but without differences between CHB, AHB and control subjects. However, compared to control subjects, CHB was associated with increased TbethiEomesdim phenotype in Vδ2+γδT-cells whereas AHB was associated with increased TbethiEomesdim phenotype in Vδ1+γδT-cells, with significant correlations between Tbet/Eomes expression in γδT-cells with their expression of NK and T-cell activation and regulatory markers. As for effector functions, IFNγ/TNF responses to phosphoantigens or PMA/Ionomycin in Vδ2+γδT-cells were weaker in AHB but preserved in CHB, without significant differences for Vδ1+γδT-cells. Furthermore, early IFNγ/TNF responses in Vδ2+ γδT-cells to brief PMA/Ionomycin stimulation correlated inversely with serum ALT but not HBV DNA. Accordingly, IFNγ/TNF responses in Vδ2+γδT-cells were weaker in patients with CHB with hepatitis flare compared to those without hepatitis flares, and this functional deficit persisted beyond clinical resolution of CHB flare. We conclude that circulating γδT-cells show distinct activation and differentiatiation in acute and chronic HBV infection as part of lymphoid stress surveillance with potential role in clinical outcomes.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Ativação Linfocitária/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Biomarcadores/análise , Estudos de Coortes , Feminino , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Receptores de Antígenos de Linfócitos T gama-delta/sangue , Adulto Jovem
9.
J Immunol ; 202(8): 2460-2472, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30877169

RESUMO

Tcrd and Tcrg display identical developmental programs that depend on the activity of the enhancers Eδ and Eγ being "on" in pre-ß-selection thymocytes to activate transcription and V(D)J recombination of the unrearranged genes and "off" in post-ß-selection CD4+CD8+ double-positive thymocytes to inhibit transcription of the rearranged genes and avoid the expression of TCR δ- and TCR γ-chains in αß T lymphocytes. Eδ and Eγ activity depends on transcription factor binding to essential Runx and Myb sites and parallels that of Notch signaling. We performed Notch gain- and loss-of-function experiments and found that Notch signaling activates Tcrd and Tcrg transcription by favoring the recruitment of RUNX1 and MYB to the enhancers. Our results suggest that the dissociation of RUNX1 and MYB from Eδ and Eγ chromatin in double-positive thymocytes, which results in enhancer inactivation, is caused by decreased Notch signaling triggered by pre-TCR signaling, thereby deciphering the molecular mechanism of Tcrd and Tcrg silencing during ß-selection. These findings reveal a novel molecular mechanism for gene regulation via Notch signaling through the recruitment of RUNX1 and MYB to enhancer chromatin during thymocyte development.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/imunologia , Elementos Facilitadores Genéticos/imunologia , Proteínas Proto-Oncogênicas c-myb/imunologia , Receptores Notch/imunologia , Transdução de Sinais/imunologia , Timócitos/imunologia , Transcrição Genética/imunologia , Animais , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Humanos , Células Jurkat , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-myb/genética , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores Notch/genética , Transdução de Sinais/genética
10.
Scand J Immunol ; 89(6): e12764, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30892738

RESUMO

Serum amyloid A (SAA) is an acute phase protein with pro-inflammatory cytokine-like properties. Recent studies have revealed that SAA promoted interleukin-17 (IL-17) production by various cells, including γδ T cells. γδ T cells are innate immune cells and express Toll-like receptor 2 (TLR2) on their surface, which is one of the SAA receptors. In this study, we investigated the relationship between γδ T cells and SAA1 through TLR2, by using hepatic SAA1-overexpressing transgenic (TG) mice. By injecting CU-CPT22, which is a TLR2 inhibitor, into the mice, we confirmed that SAA1 induced IL-17 in γδ T cells through TLR2. In vitro studies have confirmed that SAA1 increased IL-17 secretion in γδ T cells in combination with IL-23. We also observed a thickened epidermis layer and granulocyte penetration into the skin similar to the pathology of psoriasis in TG mice. In addition, strongly expressed SAA1 and penetration of γδ T cells in the skin of TG mice were detected. The exacerbation of psoriasis is associated with an increase in IL-17 levels. Therefore, these symptoms were induced by IL-17-producing γδ T cells increased by SAA1. Our study confirmed that SAA1 was a prominent protein that increased IL-17 levels through TLR2 in γδ T cells, confirming the possibility that SAA1 may exacerbate inflammatory diseases through γδ T cells.


Assuntos
Interleucina-17/biossíntese , Psoríase/patologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Proteína Amiloide A Sérica/imunologia , Receptor 2 Toll-Like/imunologia , Animais , Células Cultivadas , Subunidade p19 da Interleucina-23/biossíntese , Subunidade p19 da Interleucina-23/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Psoríase/imunologia , RNA Mensageiro/biossíntese , Receptor 2 Toll-Like/antagonistas & inibidores
11.
Proc Natl Acad Sci U S A ; 116(13): 6371-6378, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30850538

RESUMO

Tuberculosis (TB) remains a leading killer among infectious diseases, and a better TB vaccine is urgently needed. The critical components and mechanisms of vaccine-induced protection against Mycobacterium tuberculosis (Mtb) remain incompletely defined. Our previous studies demonstrate that Vγ2Vδ2 T cells specific for (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP) phosphoantigen are unique in primates as multifunctional effectors of immune protection against TB infection. Here, we selectively immunized Vγ2Vδ2 T cells and assessed the effect on infection in a rhesus TB model. A single respiratory vaccination of macaques with an HMBPP-producing attenuated Listeria monocytogenes (Lm ΔactA prfA*) caused prolonged expansion of HMBPP-specific Vγ2Vδ2 T cells in circulating and pulmonary compartments. This did not occur in animals similarly immunized with an Lm ΔgcpE strain, which did not produce HMBPP. Lm ΔactA prfA* vaccination elicited increases in Th1-like Vγ2Vδ2 T cells in the airway, and induced containment of TB infection after pulmonary challenge. The selective immunization of Vγ2Vδ2 T cells reduced lung pathology and mycobacterial dissemination to extrapulmonary organs. Vaccine effects coincided with the fast-acting memory-like response of Th1-like Vγ2Vδ2 T cells and tissue-resident Vγ2Vδ2 effector T cells that produced both IFN-γ and perforin and inhibited intracellular Mtb growth. Furthermore, selective immunization of Vγ2Vδ2 T cells enabled CD4+ and CD8+ T cells to mount earlier pulmonary Th1 responses to TB challenge. Our findings show that selective immunization of Vγ2Vδ2 T cells can elicit fast-acting and durable memory-like responses that amplify responses of other T cell subsets, and provide an approach to creating more effective TB vaccines.


Assuntos
Imunização , Ativação Linfocitária/efeitos dos fármacos , Vacinas contra a Tuberculose/imunologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Linfócitos T CD8-Positivos/imunologia , Modelos Animais de Doenças , Feminino , Memória Imunológica/imunologia , Interferon gama/metabolismo , Listeria monocytogenes/genética , Listeria monocytogenes/imunologia , Pulmão/imunologia , Pulmão/patologia , Macaca mulatta/imunologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Mycobacterium tuberculosis/efeitos dos fármacos , Organofosfatos , Fatores de Terminação de Peptídeos/genética , Fatores de Terminação de Peptídeos/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Subpopulações de Linfócitos T/imunologia , Tuberculose/patologia , Vacinas contra a Tuberculose/farmacologia , Vacinas Atenuadas/imunologia
12.
Cell Physiol Biochem ; 52(2): 354-367, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30816679

RESUMO

BACKGROUND/AIMS: Although a cross-talk between immune and endocrine systems has been well established, the precise pathways by which these signals co-regulate pro- and antiinflammatory responses on antigen-presenting cells remain poorly understood. In this work we investigated the mechanisms by which triiodothyronine (T3) controls T cell activity via dendritic cell (DC) modulation. METHODS: DCs from wild-type (WT) and IL-6-deficient mice were pulsed with T3. Cytokine production and programmed death protein ligands (PD-L) 1 and 2 expression were assayed by flow cytometry and ELISA. Interferon-regulatory factor-4 (IRF4) expression was evaluated by RT-qPCR and flow cytometry. The ability of DCs to stimulate allogenic splenocytes was assessed in a mixed lymphocyte reaction and the different profile markers were analyzed by flow cytometry and ELISA. For in vivo experiments, DCs treated with ovalbumin and T3 were injected into OTII mice. Proliferation, cytokine production, frequency of FoxP3+ regulatory T (Treg) cells and PD-1+ cells were determined by MTT assay, ELISA and flow cytometry, respectively. RESULTS: T3 endows DCs with pro-inflammatory potential capable of generating IL-17-dominant responses and down-modulating expression of PD-L1 and 2. T3-stimulated WT-DCs increased the proportion of IL-17-producing splenocytes, an effect which was eliminated when splenocytes were incubated with T3-treated DCs derived from IL-6-deficient mice. Enhanced IL-17 expression was recorded in both, CD4- and CD4+ populations and involved the IRF-4 pathway. Particularly, γδ-T cells but not natural killer (NK), NKT, B lymphocytes nor CD8+ T cells were the major source of IL-17-production from CD4- cells. Moreover, T3-conditioned DCs promoted a decrease of the FoxP3+ Treg population. Furthermore, T3 down-modulated PD-1 expression on CD4- cells thereby limiting inhibitory signals driven by this co-inhibitory pathway. Thus, T3 acts at the DC level to drive proinflammatory responses in vitro. Accordingly, we found that T3 induces IL-17 and IFNγ-dominant antigen-specific responses in vivo. CONCLUSION: These results emphasize the relevance of T3 as an additional immune-endocrine checkpoint and a novel therapeutic target to modulate IL-17-mediated pro-inflammatory responses.


Assuntos
Células Dendríticas/imunologia , Interleucina-17/imunologia , Transdução de Sinais/efeitos dos fármacos , Tri-Iodotironina/farmacologia , Animais , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Dendríticas/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/imunologia , Interleucina-17/genética , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Camundongos , Camundongos Knockout , Proteína 2 Ligante de Morte Celular Programada 1/genética , Proteína 2 Ligante de Morte Celular Programada 1/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Transdução de Sinais/imunologia
13.
PLoS One ; 14(3): e0213597, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30865691

RESUMO

Canine CD4+CD8α+ double-positive (dp) T cells of peripheral blood are a unique effector memory T cell subpopulation characterized by an increased expression of activation markers in comparison with conventional CD4+ or CD8α+ single-positive (sp) T cells. In this study, we investigated CD4+CD8α+ dp T cells in secondary lymphatic organs (i.e. mesenteric and tracheobronchial lymph nodes, spleen, Peyer's patches) and non-lymphatic tissues (i.e. lung and epithelium of the small intestine) within a homogeneous group of healthy Beagle dogs by multi-color flow cytometry. The aim of this systematic analysis was to identify the tissue-specific localization and characteristics of this distinct T cell subpopulation. Our results revealed a mature extrathymic CD1a-CD4+CD8α+ dp T cell population in all analyzed organs, with highest frequencies within Peyer's patches. Constitutive expression of the activation marker CD25 is a feature of many CD4+CD8α+ dp T cells independent of their localization and points to an effector phenotype. A proportion of lymph node CD4+CD8α+ dp T cells is FoxP3+ indicating regulatory potential. Within the intestinal environment, the cytotoxic marker granzyme B is expressed by CD4+CD8α+ dp intraepithelial lymphocytes. In addition, a fraction of CD4+CD8α+ dp intraepithelial lymphocytes and of mesenteric lymph node CD4+CD8α+ dp T cells is TCRγδ+. However, the main T cell receptor of all tissue-associated CD4+CD8α+ dp T cells could be identified as TCRαß. Interestingly, the majority of the CD4+CD8α+ dp T cell subpopulation expresses the unconventional CD8αα homodimer, in contrast to CD8α+ sp T cells, and CD4+CD8α+ dp thymocytes which are mainly CD8αß+. The presented data provide the basis for a functional analysis of tissue-specific CD4+CD8α+ dp T cells to elucidate their role in health and disease of dogs.


Assuntos
Antígenos CD4/imunologia , Antígenos CD8/imunologia , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologia , Animais , Doenças do Cão/imunologia , Cães , Feminino , Subunidade alfa de Receptor de Interleucina-2/imunologia , Masculino , Especificidade de Órgãos/imunologia
14.
Int J Mol Sci ; 20(3)2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30764544

RESUMO

Pregnancy is a state where high and stage-dependent plasticity of the maternal immune system is necessary in order to equilibrate between immunosuppression of harmful responses towards the fetus and ability to fight infections. TCR γδ cells have been implicated in the responses in infectious diseases, in the regulation of immune responses, and in tissue homeostasis and repair. The variety of functions makes γδ T cells a particularly interesting population during pregnancy. In this study, we investigated the proportion, phenotype and TCR γ and δ repertoires of γδ T cells at the maternal⁻fetal interface and in the blood of pregnant women using FACS, immunohistochemistry and spectratyping. We found an enrichment of activated and terminally differentiated pro-inflammatory γδ T-cell effectors with specific location in the human decidua during early pregnancy, while no significant changes in their counterparts in the blood of pregnant women were observed. Our spectratyping data revealed polyclonal CDR3 repertoires of the δ1, δ2 and δ3 chains and γ2, γ3, γ4 and γ5 chains and oligoclonal and highly restricted CDR3γ9 repertoire of γδ T cells in the decidua and blood of pregnant women. Early pregnancy induces recruitment of differentiated pro-inflammatory γδ T-cell effectors with diverse TCR repertoires at the maternal⁻fetal interface.


Assuntos
Decídua/imunologia , Feto/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/imunologia , Feminino , Humanos , Tolerância Imunológica , Ativação Linfocitária , Gravidez , Receptores de Antígenos de Linfócitos T gama-delta/análise , Receptores de Antígenos de Linfócitos T gama-delta/sangue
15.
Dev Comp Immunol ; 96: 78-82, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30738793

RESUMO

In order to better understand the development and function of γδ T cells in Xenopus frogs, it is necessary to determine where and when γδ T cells are found in Xenopus tissues. This study examined the expression of TCR genes, focused primarily on TCR γ, in tissues of adult and larval Xenopus laevis and provide new data about the expression pattern of these different TCR genes in this anuran amphibian. TCR gene expression was detected by RT-PCR in adult frog tissues including the thymus, spleen, skin, intestine, lung, and liver, but not the testes. TCR γ and ß genes were detected in the larval (tadpole) tail and intestine. The absence of RAG-1 expression in these larval tissues is consistent with differentiation of the T cells in the thymus. Together, these data provide evidence that migration of these cells from the thymus likely occurs relatively early in larval development. These studies provide a necessary foundation for future studies of the functions of γδ T cells in amphibians, which are placed at an intermediate position flanked by fishes on one end and mammals and chickens on the other.


Assuntos
Larva/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/metabolismo , Xenopus laevis/imunologia , Animais , Diferenciação Celular/imunologia , Genes Codificadores da Cadeia delta de Receptores de Linfócitos T , Genes Codificadores da Cadeia gama de Receptores de Linfócitos T , Proteínas de Homeodomínio/imunologia , Proteínas de Homeodomínio/metabolismo , Larva/genética , Larva/metabolismo , Metamorfose Biológica , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Subpopulações de Linfócitos T/imunologia , Xenopus laevis/genética , Xenopus laevis/metabolismo
16.
Cell ; 176(5): 967-981.e19, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30739797

RESUMO

Tissue-resident lymphocytes play a key role in immune surveillance, but it remains unclear how these inherently stable cell populations respond to chronic inflammation. In the setting of celiac disease (CeD), where exposure to dietary antigen can be controlled, gluten-induced inflammation triggered a profound depletion of naturally occurring Vγ4+/Vδ1+ intraepithelial lymphocytes (IELs) with innate cytolytic properties and specificity for the butyrophilin-like (BTNL) molecules BTNL3/BTNL8. Creation of a new niche with reduced expression of BTNL8 and loss of Vγ4+/Vδ1+ IELs was accompanied by the expansion of gluten-sensitive, interferon-γ-producing Vδ1+ IELs bearing T cell receptors (TCRs) with a shared non-germline-encoded motif that failed to recognize BTNL3/BTNL8. Exclusion of dietary gluten restored BTNL8 expression but was insufficient to reconstitute the physiological Vγ4+/Vδ1+ subset among TCRγδ+ IELs. Collectively, these data show that chronic inflammation permanently reconfigures the tissue-resident TCRγδ+ IEL compartment in CeD. VIDEO ABSTRACT.


Assuntos
Doença Celíaca/imunologia , Inflamação/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Antígenos , Butirofilinas/metabolismo , Doença Celíaca/fisiopatologia , Doença Crônica , Dieta Livre de Glúten , Glutens/metabolismo , Células HEK293 , Humanos , Inflamação/metabolismo , Mucosa Intestinal/imunologia , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo
17.
J Immunol Res ; 2019: 9020234, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30723751

RESUMO

Skin-resident γδ T cells play an important role in maintaining the immune barrier at the epithelial surface. Their roles in wound healing, regulation of immune response to injury, and reepithelialization have been characterized extensively in the mouse, though their function in human skin remains largely unknown. Human skin-resident γδ T cells sparsely populate the skin and are often small and rounded in appearance. Those in the mouse ear and back, which line the dermal barrier, are highly arborized cells with many processes extending from the cell body. To date, these cells have been studied primarily in the mouse ear and back; however, it is important to further identify and characterize γδ T cells in other body sites to better understand their function and study their contribution to injury and disease. We developed a novel method to visualize these cells in the skin (whole-mount and cryosections) that when combined with flow cytometry allowed us to assess differences in skin-resident γδ T cell numbers, morphology, and activation state in the ear, back, and footpad (chosen for their importance in immunological and pain research). In comparing cell length, number of dendritic processes, and expression of the activation marker CD69, we found that γδ T cell morphology and activation states vary significantly among the three tissue environments. Specifically, γδ T cells in the footpad are smaller, have fewer processes, and show the highest levels of activation compared to back- and ear-resident cells. Our observations suggest that our understanding of skin-resident γδ T cell functionality, drawn from the experiments performed in the ear and back tissue, may not be applicable to all skin environments. The footpad-resident cells also more closely resemble γδ T cells in human skin, suggesting that cells in this tissue environment may serve as a better translational model when studying γδ T cell function/activity.


Assuntos
Ativação Linfocitária , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Pele/citologia , Pele/imunologia , Linfócitos T/imunologia , Animais , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Citometria de Fluxo , , Humanos , Imuno-Histoquímica , Lectinas Tipo C/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Cicatrização
18.
J Immunol ; 202(6): 1859-1870, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30710048

RESUMO

Although the impact of donor graft composition on clinical outcomes after hematopoietic stem cell transplantation (HSCT) has been studied, little is known about the role of intragraft γδ TCR repertoire on clinical outcomes following HSCT. Using a high-throughput sequencing platform, we sought to analyze the TCR γ-chain (TRG) repertoire of γδ T cells within donor stem cell grafts and address its potential impact on clinical response in the corresponding patients. A total of 20 peripheral blood stem cell grafts were analyzed, and donors were classified as CMV+/- The respective acute myeloid leukemia recipients were followed for disease relapse and acute graft-versus-host disease (aGvHD) development post-HSCT. In all samples, TRG repertoire showed a reduced diversity and displayed overrepresented clones. This was more prominent in grafts from CMV+ donors, which presented a more private repertoire, lower diversity, skewed distribution, and reduced usage of the V9-JP pairing. Grafts given to nonrelapse patients presented a more public repertoire and increased presence of long sequence clonotypes. Variable-joining gene segment usage was not associated with aGvHD development, but a higher usage of V2-JP1 pairing and lower usage of V4-J2/V5-J2/V8-JP2 were observed in grafts given to nonrelapse patients. Our work identified five private overrepresented and one public CDR3 sequence (CATWDGPYYKKLF) associated with CMV infection, in addition to 12 highly frequent public sequences present exclusively in grafts given to nonrelapse patients. Our findings show that, despite CMV infection reshaping the TRG repertoire, TRG composition is not associated with aGvHD development, and several public sequences are associated with clinical remission.


Assuntos
Infecções por Citomegalovirus/imunologia , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/terapia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Transplantes/virologia , Resultado do Tratamento , Adulto , Idoso , Células Clonais , Feminino , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/virologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/virologia , Adulto Jovem
19.
Proc Natl Acad Sci U S A ; 116(7): 2634-2639, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30683721

RESUMO

Random amino acid copolymers used in the treatment of multiple sclerosis in man or experimental autoimmune encephalomyelitis (EAE) in mice [poly(Y,E,A,K)n, known as Copaxone, and poly(Y,F,A,K)n] function at least in part by generation of IL-10-secreting regulatory T cells that mediate bystander immunosuppression. The mechanism through which these copolymers induce Tregs is unknown. To investigate this question, four previously described Vα3.2 Vß14 T cell receptor (TCR) cDNAs, the dominant clonotype generated in splenocytes after immunization of SJL mice, that differed only in their CDR3 sequences were utilized to generate retrogenic mice. The high-level production of IL-10 as well as IL-5 and small amounts of the related cytokines IL-4 and IL-13 by CD4+ T cells isolated from the splenocytes of these mice strongly suggests that the TCR itself encodes information for specific cytokine secretion. The proliferation and production of IL-10 by these Tregs was costimulated by activation of glucocorticoid-induced TNF receptor (GITR) (expressed at high levels by these cells) through its ligand GITRL. A mechanism for generation of cells with this specificity is proposed. Moreover, retrogenic mice expressing these Tregs were protected from induction of EAE by the appropriate autoantigen.


Assuntos
Células-Tronco Hematopoéticas/citologia , Interleucina-10/metabolismo , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Animais , DNA Complementar , Encefalomielite Autoimune Experimental/imunologia , Feminino , Vetores Genéticos , Tolerância Imunológica , Interleucinas/metabolismo , Camundongos , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T gama-delta/genética , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Fatores de Necrose Tumoral/metabolismo
20.
Nat Immunol ; 20(2): 121-128, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30664765

RESUMO

γδ T cells have been retained as a lineage over the majority of vertebrate evolution, are able to respond to immune challenges in unique ways, and are of increasing therapeutic interest. However, one central mystery has endured: the identity of the ligands recognized by the γδ T cell antigen receptor. Here we discuss the inherent challenges in answering this question, the new opportunities provided by recent studies, and the criteria by which the field might judge success.


Assuntos
Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Ligantes , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/imunologia , Animais , Humanos , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Transdução de Sinais/imunologia , Subpopulações de Linfócitos T/metabolismo
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