RESUMO
A unique cohort of HIV-1-infected long term nonprogressors (LTNP) with normal CD4(+) T cell counts and <50 copies/ml of plasma were prospectively recruited for study. HLA typing revealed a dramatic association between the HLA B*5701 class I allele and nonprogressive infection [85% (11 of 13) vs. 9.5% (19 of 200) in progressors; P < 0. 001]. Antigen-specific CD8(+) T cells were enumerated by flow cytometric detection of intracellular IFN-gamma in response to HIV antigens and HLA B*57-gag tetramer staining. No quantitative differences in the total HIV-specific CD8(+) T cell responses were observed between B*57(+) LTNP and five B*57(+) progressors (P = 0.4). Although similar frequencies of peptide specific CD8(+) T cells were also found, the gag-specific CD8(+) T cell response in the LTNP group was highly focused on peptides previously shown to be B*57-restricted. These findings indicate that, within this phenotypically and genotypically distinct cohort, a host immune factor is highly associated with restriction of virus replication and nonprogressive disease. They also strongly suggest a mechanism of virus specific immunity that directly operates through the B*5701 molecule. Further characterization of qualitative differences in the virus-specific responses that distinguish HLA B*57(+) LTNP from progressors may ultimately define mechanisms of effective immune mediated restriction of virus replication.
Assuntos
Sobreviventes de Longo Prazo ao HIV , Soropositividade para HIV/genética , Soropositividade para HIV/imunologia , Antígenos HLA-B/genética , Replicação Viral , Alelos , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Complexo CD3/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Estudos de Coortes , Citometria de Fluxo , Proteína do Núcleo p24 do HIV/imunologia , Humanos , Imunofenotipagem , Interferon gama/imunologia , Lectinas Tipo C , Leucócitos Mononucleares/virologia , Peptídeos/metabolismo , Estudos Prospectivos , RNA Viral/sangueRESUMO
OBJECTIVES: This study evaluated a two-step intervention for mammography screening among older women. METHODS: Four hundred and sixty women, identified from physician practices, were randomized to a control or a two-step intervention (physician letter and peer counseling call) group. Women in the intervention group who obtained a mammogram received a grocery coupon. RESULTS: Over the 12 months of the study, more women in the intervention group than in the control group obtained mammograms (38% vs 16%). The most dramatic difference was in the higher odds that women in the intervention group would obtain a mammogram within 2 months (odds ratio = 10.5). CONCLUSIONS: The intervention significantly increased screening mammography. Future efforts must be multifaceted and incorporate the unique concerns of older women.
