RESUMO
OBJECTIVE: To determine the complementary determining region 3 (CDR3) length diversity of T cell receptor Vbeta repertoires of CD8+ T lymphocytes and to explore its association with viral load in individuals with HIV-1 infection. METHODS: Separation of CD8+ T cells from peripheral blood mononuclear cells (PBMCs) was carried out by using immunomagnetic beads coated with anti-CD8 antibody. Total RNAs from the purified CD8+ T lymphocytes were isolated and used to perform polymerase chain reaction (PCR) amplifications in CDR3 of 22 T cell receptor (TCR) gene families. CDR3 diversity and its association with viral load in individuals with HIV-1 infection were analyzed. RESULTS: An average diversity for all CDR3 profiles in CD8+ T cells from 9 HIV-infected individuals was significantly different as compared to 7 age-matched healthy donors (P<0.05) with the HIV-infected individuals losing diversity in the CDR3 profiles. There was positive correlation between changes in TCR CDR3 diversity and viral load (r=0.771, P<0.05). The changes in CDR3 length diversity of Vbeta families in HIV-infected individuals, particular in Vbeta2, Vbeta4, Vbeta5, Vbeta17, Vbeta20, Vbeta21, Vbeta23, Vbeta24, were statistically different from the healthy controls. CONCLUSION: HIV-1 infection might induce the loss of TCR Vbeta repertoire diversity and disrupt the CDR3 distributions within CD8+ T cells. There should be positive correlation between changes in TCR CDR3 diversity and the viral load in HIV-1 infected patients.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/genética , Infecções por HIV/virologia , Receptores de Antígenos de Linfócitos T/genética , Carga Viral , HIV-1/imunologia , Humanos , Polimorfismo GenéticoRESUMO
An imbalance of the immune-regulatory pathways plays an important role in the development of type 1 diabetes. Therefore, immunoregulatory and antiinflammatory strategies hold great potential for the prevention of this autoimmune disease. Studies have demonstrated that two serine proteinase inhibitors, alpha1-antitrypsin (AAT) and elafin, act as potent antiinflammatory agents. In the present study, we sought to develop an efficient gene therapy approach to prevent type 1 diabetes. Cohorts of 4-week-old female nonobese diabetic (NOD) mice were injected intramuscularly with rAAV1-CB-hAAT, rAAV1-CB-hElafin, or saline. AAV1 vector mediated sustained high levels of transgene expression, sufficient to overcome a humoral immune response against hAAT. AAT gene therapy, contrary to elafin and saline, was remarkably effective in preventing type 1 diabetes. T cell receptor spectratyping indicated that AAT gene therapy altered T cell repertoire diversity in splenocytes from NOD mice. Adoptive transfer experiments demonstrated that AAT gene therapy attenuated cellular immunity associated with beta cell destruction. This study demonstrates that AAT gene therapy attenuates cell-mediated autoimmunity, alters the T cell receptor repertoire, and efficiently prevents type 1 diabetes in the NOD mouse model. These results strongly suggest that rAAV1-mediated AAT gene therapy may be useful as a novel approach to prevent type 1 diabetes.
Assuntos
Diabetes Mellitus Tipo 1/prevenção & controle , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Imunidade Celular/efeitos dos fármacos , alfa 1-Antitripsina/administração & dosagem , Animais , Formação de Anticorpos , Dependovirus/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Modelos Animais de Doenças , Feminino , Técnicas de Transferência de Genes , Humanos , Injeções Intramusculares , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas Secretadas Inibidoras de Proteinases , Proteínas/administração & dosagem , Proteínas/genética , Proteínas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/uso terapêutico , alfa 1-Antitripsina/biossíntese , alfa 1-Antitripsina/genéticaRESUMO
To examine the role of T cell receptor (TCR) in gammadelta T cells in adaptive immunity, a macaque model was used to follow Vgamma2Vdelta2+ T cell responses to mycobacterial infections. These phosphoantigen-specific gammadelta T cells displayed major expansion during Mycobacterium bovis Bacille Calmette-Guérin (BCG) infection and a clear memory-type response after BCG reinfection. Primary and recall expansions of Vgamma2Vdelta2+ T cells were also seen during Mycobacterium tuberculosis infection of naive and BCG-vaccinated macaques, respectively. This capacity to rapidly expand coincided with a clearance of BCG bacteremia and immunity to fatal tuberculosis in BCG-vaccinated macaques. Thus, Vgamma2Vdelta2+ T cells may contribute to adaptive immunity to mycobacterial infections.
