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1.
Adv Exp Med Biol ; 1248: 7-32, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32185705

RESUMO

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is an inhibitory receptor belonging to the CD28 immunoglobulin subfamily, expressed primarily by T-cells. Its ligands, CD80 and CD86, are typically found on the surface of antigen-presenting cells and can either bind CD28 or CTLA-4, resulting in a costimulatory or a co-inhibitory response, respectively. Because of its dampening effect, CTLA-4 is a crucial regulator of T-cell homeostasis and self-tolerance. The mechanisms by which CTLA-4 exerts its inhibitory function can be categorized as either cell-intrinsic (affects the CTLA-4 expressing T-cell) or cell-extrinsic (affects secondary cells). Research from the last decade has shown that CTLA-4 mainly acts in a cell-extrinsic manner via its competition with CD28, CTLA-4-mediated trans-endocytosis of CD80 and CD86, and its direct tolerogenic effects on the interacting cell. Nonetheless, intrinsic CTLA-4 signaling has been implicated in T-cell motility and the regulation of CTLA-4 its subcellular localization amongst others. CTLA-4 is well recognized as a key immune checkpoint and has gained significant momentum as a therapeutic target in the field of autoimmunity and cancer. In this chapter, we describe the role of costimulation in immune response induction as well as the main mechanisms by which CTLA-4 can inhibit this process.


Assuntos
Antígeno CTLA-4/imunologia , Antígeno CTLA-4/metabolismo , Animais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Antígenos CD28/metabolismo , Humanos , Ativação Linfocitária
2.
Immunity ; 52(2): 313-327.e7, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32049052

RESUMO

T cell responses upon infection display a remarkably reproducible pattern of expansion, contraction, and memory formation. If the robustness of this pattern builds entirely on signals derived from other cell types or if activated T cells themselves contribute to the orchestration of these population dynamics-akin to bacterial quorum regulation-is unclear. Here, we examined this question using time-lapse microscopy, genetic perturbation, bioinformatic predictions, and mathematical modeling. We found that ICAM-1-mediated cell clustering enabled CD8+ T cells to collectively regulate the balance between proliferation and apoptosis. Mechanistically, T cell expressed CD80 and CD86 interacted with the receptors CD28 and CTLA-4 on neighboring T cells; these interactions fed two nested antagonistic feedback circuits that regulated interleukin 2 production in a manner dependent on T cell density as confirmed by in vivo modulation of this network. Thus, CD8+ T cell-population-intrinsic mechanisms regulate cellular behavior, thereby promoting robustness of population dynamics.


Assuntos
Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Antígeno CTLA-4/metabolismo , Animais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Comunicação Celular , Contagem de Células , Linhagem Celular , Sobrevivência Celular , Rastreamento de Células , Células Dendríticas/imunologia , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-2/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Teóricos
3.
Nat Commun ; 11(1): 931, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32071302

RESUMO

Intrinsic malignant brain tumors, such as glioblastomas are frequently resistant to immune checkpoint blockade (ICB) with few hypermutated glioblastomas showing response. Modeling patient-individual resistance is challenging due to the lack of predictive biomarkers and limited accessibility of tissue for serial biopsies. Here, we investigate resistance mechanisms to anti-PD-1 and anti-CTLA-4 therapy in syngeneic hypermutated experimental gliomas and show a clear dichotomy and acquired immune heterogeneity in ICB-responder and non-responder tumors. We made use of this dichotomy to establish a radiomic signature predicting tumor regression after pseudoprogression induced by ICB therapy based on serial magnetic resonance imaging. We provide evidence that macrophage-driven ICB resistance is established by CD4 T cell suppression and Treg expansion in the tumor microenvironment via the PD-L1/PD-1/CD80 axis. These findings uncover an unexpected heterogeneity of response to ICB in strictly syngeneic tumors and provide a rationale for targeting PD-L1-expressing tumor-associated macrophages to overcome resistance to ICB.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Glioma/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos , Animais , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-1/imunologia , Antígeno B7-1/metabolismo , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Antígeno CTLA-4/metabolismo , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/imunologia , Feminino , Glioma/diagnóstico por imagem , Glioma/genética , Glioma/imunologia , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Imagem por Ressonância Magnética , Masculino , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
4.
Scand J Immunol ; 91(5): e12872, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32048307

RESUMO

γδ T cells play important roles in the development of rheumatoid arthritis (RA) through their antigen-presenting capacity, release of pro-inflammatory cytokines, immunomodulatory properties, interaction with CD4+ CD25+ Tregs and promotion of antibody production by helping B cells. Although prostaglandin E2 (PGE2) was proved to have the ability to enhance the antigen-presenting function of dendritic cells and IL-17 production of CD4+ αß T cells in RA, the role of PGE2 in γδ T cells from RA disease has not yet been clarified. The goal of this study was to determine the role of PGE2 in γδ T cells in RA. We first demonstrated that the population of γδT17 cells increased in patients with RA compared to healthy controls. Then, IL-17A level in patients with RA was shown to increase compared to healthy controls. After adding PGE2 to γδ T cells from patients with RA, the IL-17A level increased accordingly, and the expression of the costimulatory molecules, CD80 and CD86, on these cells also increased. These results suggest that PEG2 can increase the production of IL-17A and the expression of CD80 and CD86 on γδ T cells in patients with RA. These findings will benefit to explore new therapeutic targets for RA disease.


Assuntos
Artrite Reumatoide/etiologia , Artrite Reumatoide/metabolismo , Dinoprostona/metabolismo , Regulação da Expressão Gênica , Interleucina-17/biossíntese , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Adulto , Idoso , Artrite Reumatoide/patologia , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Antígeno B7-2/genética , Antígeno B7-2/metabolismo , Biomarcadores , Feminino , Humanos , Imunofenotipagem , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade
5.
Ann Otol Rhinol Laryngol ; 129(3): 245-255, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31646875

RESUMO

OBJECTIVES: Diesel exhaust particles (DEP)s are notorious ambient pollutants composed of a complex mixture of a carbon core and diverse chemical irritants. Several studies have demonstrated significant relationships between DEP exposure and serious nasal inflammatory response in vitro, but available information regarding underlying networks in terms of gene expression changes has not sufficiently explained potential mechanisms of DEP-induced nasal damage, especially in vivo. METHODS: In the present study, we identified DEP-induced gene expression profiles under short-term and long-term exposure, and identified signaling pathways based on microarray data for understanding effects of DEP exposure in the mouse nasal cavity. RESULTS: Alteration in gene expression due to DEP exposure provokes an imbalance of the immune system via dysregulated inflammatory markers, predicted to disrupt protective responses against harmful exogenous substances in the body. Several candidate markers were identified after validation using qRT-PCR, including S100A9, CAMP, IL20, and S100A8. CONCLUSIONS: Although further mechanistic studies are required for verifying the utility of the potential biomarkers suggested by the present study, our in vivo results may provide meaningful suggestions for understanding the complex cellular signaling pathways involved in DEP-induced nasal damages.


Assuntos
Expressão Gênica , Rinite/induzido quimicamente , Emissões de Veículos/toxicidade , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Biomarcadores/metabolismo , Calgranulina A/genética , Calgranulina A/metabolismo , Calgranulina B/genética , Calgranulina B/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Camundongos Endogâmicos BALB C , Modelos Animais , Testes de Provocação Nasal , Análise de Sequência com Séries de Oligonucleotídeos , RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Rinite/metabolismo , Transdução de Sinais , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
6.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(11): 973-978, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31878992

RESUMO

Objective To investigate the autophagy and the expression of CD40 and CD80 of dendritic cells (DCs) induced by hypoxia and lipopolysaccharide (LPS). Methods DCs were divided into normal group, hypoxia group, lipopolysaccharide (LPS) treatment group and hypoxia combined with LPS treatment group. Each group was treated for 24 hours, and the cell proliferation was detected by MTT assay. The protein levels of autophagy microtubule-associated protein 1 light chain 3I (LC3I), LC3II and beclin1 were detected by Western blot analysis. The formation of autophagosomes in DCs was observed under a transmission electron microscope after LPS treatment. The expression of CD40 and CD80 on DCs was detected by flow cytometry and immunofluorescence cytochemical staining. Results Hypoxia and LPS could induce autophagy in mouse DCs and increase the expression of CD40 and CD80 on their surface. After hypoxia combined with LPS treatment, autophagy in DCs was significantly enhanced; more autophagosomes were formed; and the expression of co-stimulatory molecules CD40 and CD80 were raised. Conclusion Hypoxia and LPS can induce autophagy and increase the expression of CD40 and CD80 in mouse DCs.


Assuntos
Autofagia , Antígeno B7-1/metabolismo , Antígenos CD40/metabolismo , Células Dendríticas/citologia , Animais , Proteína Beclina-1/metabolismo , Hipóxia Celular , Células Cultivadas , Lipopolissacarídeos , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo
7.
Immunity ; 51(6): 1059-1073.e9, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31757674

RESUMO

Combined immunotherapy targeting the immune checkpoint receptors cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1), or CTLA-4 and the PD-1 ligand (PD-L1) exhibits superior anti-tumor responses compared with single-agent therapy. Here, we examined the molecular basis for this synergy. Using reconstitution assays with fluorescence readouts, we found that PD-L1 and the CTLA-4 ligand CD80 heterodimerize in cis but not trans. Quantitative biochemistry and cell biology assays revealed that PD-L1:CD80 cis-heterodimerization inhibited both PD-L1:PD-1 and CD80:CTLA-4 interactions through distinct mechanisms but preserved the ability of CD80 to activate the T cell co-stimulatory receptor CD28. Furthermore, PD-L1 expression on antigen-presenting cells (APCs) prevented CTLA-4-mediated trans-endocytosis of CD80. Atezolizumab (anti-PD-L1), but not anti-PD-1, reduced cell surface expression of CD80 on APCs, and this effect was negated by co-blockade of CTLA-4 with ipilimumab (anti-CTLA-4). Thus, PD-L1 exerts an immunostimulatory effect by repressing the CTLA-4 axis; this has implications to the synergy of anti-PD-L1 and anti-CTLA-4 combination therapy.


Assuntos
Antígeno B7-1/metabolismo , Antígeno B7-H1/metabolismo , Antígenos CD28/metabolismo , Antígeno CTLA-4/antagonistas & inibidores , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Imunoterapia/métodos , Ipilimumab/farmacologia , Células Jurkat , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/imunologia , Neoplasias/terapia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
8.
Adv Exp Med Biol ; 1189: 25-51, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31758530

RESUMO

Immune responses are controlled by the optimal balance between protective immunity and immune tolerance. T-cell receptor (TCR) signals are modulated by co-signaling molecules, which are divided into co-stimulatory and co-inhibitory molecules. By expression at the appropriate time and location, co-signaling molecules positively and negatively control T-cell differentiation and function. For example, ligation of the CD28 on T cells provides a critical secondary signal along with TCR ligation for naive T-cell activation. In contrast, co-inhibitory signaling by the CD28-B7 family is important to regulate immune homeostasis and host defense, as these signals limit the strength and duration of immune responses to prevent autoimmunity. At the same time, microorganisms or tumor cells can use these pathways to establish an immunosuppressive environment to inhibit the immune responses against themselves. Understanding these co-inhibitory pathways will support the development of new immunotherapy for the treatment of tumors and autoimmune and infectious diseases. Here, we introduce diverse molecules belonging to the members of the CD28-B7 family.


Assuntos
Antígeno B7-1/metabolismo , Antígenos CD28/metabolismo , Ativação Linfocitária , Transdução de Sinais , Linfócitos T/citologia , Humanos , Tolerância Imunológica , Imunoterapia
9.
J Immunol Res ; 2019: 3161750, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31485459

RESUMO

Rheumatoid arthritis (RA) is a multifactorial autoimmune disease whose main hallmark is inflammation and destruction of the joints. Two cell types within the synovium that play an important role in RA are fibroblast-like synoviocytes (FLS) and macrophages. The latter innate immune cells show a high plasticity in their phenotype and are central in inflammatory processes. Low-dose radiotherapy (LD-RT) with particularly a single dose of 0.5 Gy has been demonstrated to have a positive impact on pain, inflammation, and bone in inflamed joints. We now examined for the first time how LD-RT influences FLS and bone marrow-derived macrophages in co-culture systems of an experimental model of RA to reveal further mechanisms of immune modulatory effects of low and intermediate dose of ionizing radiation. For this, the bone marrow of hTNF-α tg mice was differentiated either with cytokines to obtain key macrophage phenotypes (M0, M1, and M2) or with supernatants (SN) of untreated or irradiated FLS. Flow cytometry analyses were used to analyse the impact of radiation (0.1, 0.5, 1.0, and 2.0 Gy) on the phenotype of macrophages in the presence or absence of SN of FLS. LD-RT had no impact on cytokine-mediated macrophage polarization in M0, M1, or M2 macrophages. However, SN of irradiated FLS particularly reduced CD206 expression on macrophages. Macrophage phenotype was stable when being in contact with SN of nonirradiated FLS, but significantly increased surface expression of CD206 and slightly decreased CD80 and CD86 expression were observed when macrophage themselves were irradiated with 0.5 Gy under these microenvironmental conditions, again highlighting discontinuous dose dependencies in the low and intermediate dose range. One can conclude that FLS-dependent microenvironmental conditions have a slight influence on the modulation of macrophage phenotype under radiation exposure conditions. Future studies are needed to reveal the impact of radiation exposure on the functions of treated macrophages under such microenvironmental conditions.


Assuntos
Artrite Reumatoide/radioterapia , Macrófagos/efeitos da radiação , Sinoviócitos/efeitos da radiação , Animais , Artrite Reumatoide/imunologia , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Diferenciação Celular , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Inflamação/imunologia , Lectinas Tipo C/metabolismo , Ativação de Macrófagos/efeitos da radiação , Macrófagos/imunologia , Macrófagos/metabolismo , Lectinas de Ligação a Manose/metabolismo , Camundongos , Camundongos Transgênicos , Fenótipo , Doses de Radiação , Receptores de Superfície Celular/metabolismo , Sinoviócitos/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
10.
Nat Commun ; 10(1): 3106, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308374

RESUMO

Immune responses need to be controlled tightly to prevent autoimmune diseases, yet underlying molecular mechanisms remain partially understood. Here, we identify biallelic mutations in three patients from two unrelated families in differentially expressed in FDCP6 homolog (DEF6) as the molecular cause of an inborn error of immunity with systemic autoimmunity. Patient T cells exhibit impaired regulation of CTLA-4 surface trafficking associated with reduced functional CTLA-4 availability, which is replicated in DEF6-knockout Jurkat cells. Mechanistically, we identify the small GTPase RAB11 as an interactor of the guanine nucleotide exchange factor DEF6, and find disrupted binding of mutant DEF6 to RAB11 as well as reduced RAB11+CTLA-4+ vesicles in DEF6-mutated cells. One of the patients has been treated with CTLA-4-Ig and achieved sustained remission. Collectively, we uncover DEF6 as player in immune homeostasis ensuring availability of the checkpoint protein CTLA-4 at T-cell surface, identifying a potential target for autoimmune and/or cancer therapy.


Assuntos
Antígeno CTLA-4/metabolismo , Proteínas de Ligação a DNA/deficiência , Fatores de Troca do Nucleotídeo Guanina/deficiência , /genética , Antígeno B7-1/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Técnicas de Inativação de Genes , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/imunologia , Homeostase , Humanos , Células Jurkat , Linfócitos T/metabolismo , Linfócitos T/fisiologia , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
11.
Hum Immunol ; 80(10): 855-862, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31285077

RESUMO

High mortality in pregnant women is a characteristic of hepatitis E virus (HEV) infection. Role of monocytes/T cells in HEV infection during pregnancy is still unclear. We compared CD14+monocytes and CD4+T cells by flow-cytometry in hepatitis-E patients including 13 pregnant (Antenatal care, ANC), 25 non-ANC patients and respective controls (12 and 20). Non-ANC-patients showed significantly higher frequency of monocytes with increased expression of CD80, CD86 and HLA-DR than control individuals (p < 0.001). Healthy pregnancy was associated with increased frequency of monocytes with higher CD80 expression and lower levels of HLA-DR (p < 0.05) compared to non-ANC controls. ANC-patients exhibited elevated levels of monocytes (p < 0.01) with higher expression of CD80 (p < 0.001) and reduced levels of HLA-DR and CD86 (p < 0.05) when compared with non-ANC patients. TLR2 and TLR4 surface expression on monocytes was higher in non-ANC-patients (p < 0.00) and lower in the ANC-patients (p < 0.01). Healthy-ANCs exhibited lower TLR4 expression on monocytes (p < 0.05). HEV infection did not change the frequency of CD4+ and CD4+CD28+T cells in patients' group (p > 0.05). Compared to respective controls, CD137+ and CD152+CD4+T cells were higher (p < 0.05) in both patients' categories. Higher levels of CD152+CD4+T cells (p < 0.001) was noted in healthy pregnant women. Among patients' groups, the CD4+T cells and their subpopulation were not different (p > 0.05). We found higher and reduced levels of circulating inflammatory cytokines (IL12, TNFα, IL6 and IL8; miliplex-assay) in non-ANC and ANC-patients respectively. In conclusion, on contrary to the classical activation of CD14+monocytes in the non-ANC-patients, impaired response was evident in the ANC-patients while the CD4+T cell populations were similar in the patient groups.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Vírus da Hepatite E/imunologia , Hepatite E/genética , Monócitos/imunologia , Fenótipo , Adulto , Antígeno B7-1/genética , Antígeno B7-1/metabolismo , Antígeno B7-2/genética , Antígeno B7-2/metabolismo , Citocinas/sangue , Feminino , Antígenos HLA-DR/genética , Antígenos HLA-DR/metabolismo , Hepatite E/patologia , Humanos , Índia , Receptores de Lipopolissacarídeos/genética , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Gravidez , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Adulto Jovem
12.
J Immunol Res ; 2019: 9124326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31183394

RESUMO

Vaccination is the most effective tool against infectious diseases. Subunit vaccines are safer compared to live-attenuated vaccines but are less immunogenic and need to be delivered with an adjuvant. Adjuvants are essential for enhancing vaccine potency by improving humoral and cell-mediated immune responses. Only a limited number of adjuvants are licensed for human vaccines, and their mode of action is still not clear. Leishmania eukaryotic initiation factor (LeIF) has been described having a dual role, as a natural adjuvant and as an antigen that possesses advantageous immunomodulatory properties. In this study, we assessed the adjuvant properties of recombinant Leishmania infantum eukaryotic initiation factor (LieIF) through in vitro and in vivo assays. LieIF was intraperitoneally administered in combination with the protein antigen ovalbumin (OVA), and the widely used alum was used as a reference adjuvant. Our in vitro studies using J774A.1 macrophages showed that LieIF induced stimulatory effects as demonstrated by the enhanced surface expression of CD80 and CD86 co-stimulatory molecules and the induced production of the immune mediators NO and MIP-1α. Additionally, LieIF co-administration with OVA in an in vivo murine model induced a proinflammatory environment as demonstrated by the elevated expression of TNF-α, IL-1ß, and NF-κB2 genes in peritoneal exudate cells (PEC). Furthermore, PEC derived from OVA-LieIF-immunized mice exhibited elevated expression of CD80 molecule and production of NO and MIP-1α in culture supernatants. Moreover, LieIF administration in the peritoneum of mice resulted in the recruitment of neutrophils and monocytes at 24 h post-injection. Also, we showed that this immunopotentiating effect of LieIF did not depend on the induction of uric acid danger signal. These findings suggest the potential use of LieIF as adjuvant in new vaccine formulations against different infectious diseases.


Assuntos
Adjuvantes Imunológicos , Fatores de Iniciação em Eucariotos/imunologia , Inflamação/imunologia , Leishmania infantum/fisiologia , Leishmaniose Visceral/imunologia , Macrófagos/imunologia , Proteínas de Protozoários/imunologia , Animais , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Fatores de Iniciação em Eucariotos/genética , Feminino , Humanos , Interleucina-1beta/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Infiltração de Neutrófilos , Ovalbumina/imunologia , Proteínas de Protozoários/genética , Fator de Necrose Tumoral alfa/metabolismo
13.
Ann Otol Rhinol Laryngol ; 128(6_suppl): 45S-51S, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31092026

RESUMO

OBJECTIVES: The aim of this study was to investigate the effect of regulatory T cells (Tregs) on B-cell immune responses against outer membrane protein (OMP) from nontypeable Haemophilus influenzae (NTHi) in vitro, to clarify its exact mechanism from an immunologic standpoint. METHODS: Mice were vaccinated intranasally with OMP to induce OMP-specific immune responses in the nasal mucosa. Mononuclear cells (MNCs) were collected from the nasal mucosa, and Tregs and helper T (Th) cells were isolated separately from the spleens of those mice. Three different cell culture groups were allocated: MNCs cocultured with Tregs, MNCs cocultured with Th cells, and MNCs cultured alone. At 24 and 72 hours after cell culture, the concentrations of various cytokines and antibodies in culture supernatants were measured to assess the effects of Tregs and Th cells on B-cell responses. Cytokine levels and specific anti-OMP antibody levels in culture media were determined using enzyme-linked immunosorbent assay. CD69 or CD80 expression on B220-positive cells was detected using flow cytometric analysis. RESULTS: Th1 and Th2 cytokine concentrations were significantly elevated in the 3 groups incubated with OMP from 24 to 72 hours. Additionally, interleukin-10 levels were significantly higher in the Treg and Th groups than in the control group. Levels of OMP-specific immunoglobulin A did not differ significantly among the groups. The ratios of CD69+B220+ B2 cells were nearly the same in the 3 groups; however, the ratio of CD80+B220+ B2 cells was higher in the control group than in the Treg and Th groups during incubation. CONCLUSIONS: Tregs and Th cells did not affect OMP-specific immunoglobulin A production in this study. However, these cells may partially inhibit B-cell functions, such as T-cell activation. These inhibitory effects may be related to interleukin-10.


Assuntos
Linfócitos B/fisiologia , Haemophilus influenzae/imunologia , Linfócitos T Reguladores/fisiologia , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Antígeno B7-1/metabolismo , Proteínas da Membrana Bacteriana Externa , Técnicas de Cultura de Células , Citocinas/metabolismo , Imunidade nas Mucosas , Lectinas Tipo C/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Mucosa Nasal
14.
Science ; 364(6440): 558-566, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31000591

RESUMO

Targeted blockade of PD-1 with immune checkpoint inhibitors can activate T cells to destroy tumors. PD-1 is believed to function mainly at the effector, but not in the activation, phase of T cell responses, yet how PD-1 function is restricted at the activation stage is currently unknown. Here we demonstrate that CD80 interacts with PD-L1 in cis on antigen-presenting cells (APCs) to disrupt PD-L1/PD-1 binding. Subsequently, PD-L1 cannot engage PD-1 to inhibit T cell activation when APCs express substantial amounts of CD80. In knock-in mice in which cis-PD-L1/CD80 interactions do not occur, tumor immunity and autoimmune responses were greatly attenuated by PD-1. These findings indicate that CD80 on APCs limits the PD-1 coinhibitory signal, while promoting CD28-mediated costimulation, and highlight critical components for induction of optimal immune responses.


Assuntos
Antígeno B7-1/metabolismo , Antígeno B7-H1/metabolismo , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T/imunologia , Animais , Autoimunidade , Antígeno B7-1/genética , Antígenos CD28/metabolismo , Células Dendríticas/imunologia , Técnicas de Introdução de Genes , Humanos , Imunoterapia , Ativação Linfocitária , Camundongos , Camundongos Mutantes , Neoplasias/terapia , Ligação Proteica
15.
Mol Med Rep ; 19(4): 2591-2598, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30720127

RESUMO

Gut microbiota plays a pivotal role in not only the gastrointestinal (GI) immune system but also GI motility and metabolism. Antibiotic treatments are likely to affect the gut flora and GI immune system, subsequently disturbing GI motility and body metabolism. In the present study, we investigated antibiotic­induced alterations of body metabolism and GI motility in association with the macrophage profile in the colon. Specific pathogen­free (SPF) mice (ICR; 6 weeks old; female) were orally administered vancomycin (0.2 mg/ml) in drinking water for 5 weeks, and subsequent changes in pathophysiology were observed. The expression of CD80 and CD163 was examined by immunohistochemistry and the expression of cytokines in colonic tissues was evaluated by reverse transcription­quantitative polymerase chain reaction. The gastrointestinal transit time (GITT) was measured by administration of carmine red (6% w/v) solution. In the vancomycin­treated SPF mice, significant increases in body weight, cecum weight and GITT were observed compared with the controls. The number of CD80­positive M1 macrophages and the expression of interferon­Î³ and interleukin­12 were significantly increased, whereas, the numbers of CD163­positive M2 macrophages in the mucosal and muscular layers were decreased in the colon of vancomycin­treated mice. GITT was positively correlated with the number of CD80­positive M1 macrophages in the colonic mucosa; however, was negatively correlated with the number of CD163­positive M2 macrophages in the mucosal and muscular layers. Therefore, it was suggested that antibiotic treatment affects body metabolism and GI motility, accompanied by alterations in macrophage polarization and cytokine profiles in the colon.


Assuntos
Colo/efeitos dos fármacos , Colo/imunologia , Motilidade Gastrointestinal/efeitos dos fármacos , Macrófagos/imunologia , Obesidade/etiologia , Vancomicina/farmacologia , Animais , Antígeno B7-1/metabolismo , Biomarcadores , Colo/metabolismo , Colo/fisiopatologia , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica , Macrófagos/metabolismo , Camundongos , Obesidade/metabolismo , Tetraspanina 30/metabolismo
16.
Am J Physiol Renal Physiol ; 316(4): F723-F731, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30672713

RESUMO

LPS-induced sepsis is a leading cause of acute kidney injury (AKI) in critically ill patients. LPS may induce CD80 expression in podocytes with subsequent onset of proteinuria, a risk factor for progressive chronic kidney disease (CKD) frequently observed after AKI. This study aimed to investigate the therapeutic efficacy of LPS removal in decreasing albuminuria through the reduction of podocyte CD80 expression. Between January 2015 and December 2017, 70 consecutive patients with Gram-negative sepsis-induced AKI were randomized to either have coupled plasma filtration and adsorption (CPFA) added to the standard care ( n = 35) or not ( n = 35). To elucidate the possible relationship between LPS-induced renal damage, proteinuria, and CD80 expression in Gram sepsis, a swine model of LPS-induced AKI was set up. Three hours after LPS infusion, animals were treated or not with CPFA for 6 h. Treatment with CPFA significantly reduced serum cytokines, C-reactive protein, procalcitonin, and endotoxin levels in patients with Gram-negative sepsis-induced AKI. CPFA significantly lowered also proteinuria and CD80 urinary excretion. In the swine model of LPS-induced AKI, CD80 glomerular expression, which was undetectable in control pigs, was markedly increased at the podocyte level in LPS-exposed animals. CPFA significantly reduced LPS-induced proteinuria and podocyte CD80 expression in septic pigs. Our data indicate that LPS induces albuminuria via podocyte expression of CD80 and suggest a possible role of timely LPS removal in preventing the maladaptive repair of the podocytes and the consequent increased risk of CKD in sepsis-induced AKI.


Assuntos
Albuminúria/metabolismo , Antígeno B7-1/metabolismo , Estado Terminal , Infecções por Bactérias Gram-Positivas/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Sepse/metabolismo , APACHE , Adsorção , Adulto , Idoso , Animais , Citocinas/metabolismo , Feminino , Filtração , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/microbiologia , Suínos
17.
Future Oncol ; 15(5): 473-483, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30628844

RESUMO

AIM: To study the expression and prognostic significance of CD80 in patients with gastric adenocarcinoma. Materials & methods: Real-time quantitative PCR, western blot and immunohistochemistry were performed to detect the expression of CD80 in gastric cancer tissues and matched adjacent normal tissues. Double immunohistochemical staining was performed to preliminary examine the relationship between CD80+ cells and CD8+ cytotoxic T lymphocytes. RESULTS: The expression of CD80 was downregulated in tumor tissues compared with normal tissues (p = 0.002). Immunohistochemistry analysis showed that 49 (39.8%) of 123 patients with gastric cancer demonstrated reduced CD80 expression, which was correlated with the tumor differentiation grade. CONCLUSION: Our data suggest that reduced CD80 expression independently predicts a poor prognosis in patients with gastric adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Antígeno B7-1/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Antígeno B7-1/genética , Biomarcadores Tumorais , Feminino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias Gástricas/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
18.
Ther Drug Monit ; 41(1): 11-18, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30633722

RESUMO

BACKGROUND: Belatacept (Nulojix; Bristol-Myers Squibb, New York, NY) is a biological immunosuppressive drug used for the prophylaxis of acute rejection after renal transplantation. Few studies have described belatacept pharmacokinetics, and the effect of therapeutic drug monitoring has not been investigated. We have developed a drug-capture assay (using drug target) to measure belatacept in serum and applied this assay in a pharmacokinetic study in renal transplant recipients. METHODS: CD80 was used to trap belatacept onto streptavidin-coated wells. Captured drug was quantified using Eu-labeled protein A and time-resolved fluorescence. The assay was applied in a pilot pharmacokinetic study in renal transplanted patients receiving belatacept infusions. Belatacept serum concentrations were determined at several time points between belatacept infusions. A simple population pharmacokinetic model was developed to visualize measured and predicted belatacept serum concentrations. RESULTS: The assay range was 0.9-30 mg/L with accuracy within 91%-99% and coefficients of variation ranging from 1.2% to 3.6%. Predilution extended the measurement range to 130 mg/L with an accuracy of 90% and coefficients of variation of 3.8%. Samples were stable during storage at 4°C for 15 days and during 2 freeze-thaw cycles. Belatacept concentrations were determined in a total of 203 serum samples collected during 26 infusion intervals from 5 renal transplant recipients. The population pharmacokinetic model visualized both measured and predicted concentrations. CONCLUSIONS: We have developed an automated, accurate, and precise assay for the determination of belatacept serum concentrations. The assay was successfully applied in a pharmacokinetic study in renal transplant recipients receiving belatacept infusions.


Assuntos
Abatacepte/sangue , Monitoramento de Medicamentos/métodos , Imunossupressores/sangue , Adulto , Idoso , Antígeno B7-1/metabolismo , Feminino , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Transplantados
19.
J Clin Lab Anal ; 33(3): e22713, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30499177

RESUMO

BACKGROUND: Chronic renal failure (CRF) has become a major public health concern, which increases the risk of stroke and systemic thromboembolism. Therefore, therapeutic strategies are in urgent requirement. This study was conducted for investigating efficacy of hemodialysis (HD), hemodiafiltration (HDF), and hemoperfusion (HP) in patients with CRF and the correlation with the presence of complications following HD therapy. METHODS: The therapeutic effect, living quality, biochemical indicators, and dry weight were detected before and after the treatment regimens. Flow cytometry was conducted to detect expressions of dendritic cell markers (CD40 and CD80) and platelet activation markers (CD62P and P10), and the relationship between their expression and therapeutic effect as well as the association of these expressions with complications was analyzed. RESULTS: After HD therapy, patients presented with decreased serum creatinine, serum phosphorus, triglyceride, parathyroid hormone, and ß2 -MG expression; increased hemoglobin, plasma albumin expressions, and dry weight; and enhanced therapeutic effect and living quality. CD62P and P10 expressions decreased, while CD40 and CD80 expressions increased following HD therapy. The therapeutic effect improved in patients with low expressions of CD40 and CD80 and high expressions of CD62P and P10 following HP treatment and complications were lower after treatment of HDF and HP. CONCLUSION: The aforementioned results indicated that CRF patients treated with HP exhibited higher expression of CD40 and CD80 and lower expression of CD62P and P10, suggesting that HP is conferred to have better efficacy than HDF and HD. Therefore, HP may be a promising clinical regimen for treatment of CRF patients.


Assuntos
Antígeno B7-1/metabolismo , Antígenos CD40/metabolismo , Falência Renal Crônica , Selectina-P/metabolismo , Ativação Plaquetária/fisiologia , Diálise Renal , Adulto , Idoso , Antígeno B7-1/análise , Biomarcadores/análise , Biomarcadores/metabolismo , Antígenos CD40/análise , Células Dendríticas/química , Células Dendríticas/citologia , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/metabolismo , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Selectina-P/análise
20.
J Virol ; 93(3)2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30404803

RESUMO

Herpes simplex virus type 1 (HSV-1) has the ability to delay its clearance from the eye during ocular infection. Here, we show that ocular infection of mice with HSV-1 suppressed expression of the costimulatory molecule CD80 but not CD86 in the cornea. The presence of neutralizing anti-HSV-1 antibodies did not alleviate this suppression. At the cellular level, HSV-1 consistently downregulated the expression of CD80 by dendritic cells (DCs) but not by other antigen-presenting cells. Furthermore, flow cytometric analysis of HSV-1-infected corneal cells during a 7-day period reduced CD80 expression in DCs but not in B cells, macrophages, or monocytes. This suppression was associated with the presence of virus. Similar results were obtained using infected or transfected spleen cells or bone marrow-derived DCs. A combination of roscovitine treatment, transfection with immediate early genes (IE), and infection with a recombinant HSV-1 lacking the ICP22 gene shows the importance of ICP22 in downregulation of the CD80 promoter but not the CD86 promoter in vitro and in vivo At the mechanistic level, we show that the HSV-1 immediate early gene ICP22 binds the CD80 promoter and that this interaction is required for HSV-1-mediated suppression of CD80 expression. Conversely, forced expression of CD80 by ocular infection of mice with a recombinant HSV-1 exacerbated corneal scarring in infected mice. Taken together, these studies identify ICP22-mediated suppression of CD80 expression in dendritic cells as central to delayed clearance of the virus and limitation of the cytopathological response to primary infection in the eye.IMPORTANCE HSV-1-induced eye disease is a major public health problem. Eye disease is associated closely with immune responses to the virus and is exacerbated by delayed clearance of the primary infection. The immune system relies on antigen-presenting cells of the innate immune system to activate the T cell response. We found that HSV-1 utilizes a robust and finely targeted mechanism of local immune evasion. It downregulates the expression of the costimulatory molecule CD80 but not CD86 on resident dendritic cells irrespective of the presence of anti-HSV-1 antibodies. The effect is mediated by direct binding of HSV-1 ICP22, the product of an immediate early gene of HSV-1, to the promoter of CD80. This immune evasion mechanism dampens the host immune response and, thus, reduces eye disease in ocularly infected mice. Therefore, ICP22 may be a novel inhibitor of CD80 that could be used to modulate the immune response.


Assuntos
Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Células Dendríticas/metabolismo , Infecções Oculares/metabolismo , Herpes Simples/metabolismo , Herpesvirus Humano 1/patogenicidade , Proteínas Imediatamente Precoces/metabolismo , Animais , Antígeno B7-1/genética , Antígeno B7-2/genética , Córnea/metabolismo , Córnea/virologia , Células Dendríticas/virologia , Infecções Oculares/genética , Infecções Oculares/virologia , Feminino , Regulação da Expressão Gênica , Herpes Simples/genética , Herpes Simples/virologia , Proteínas Imediatamente Precoces/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas , Replicação Viral
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