RESUMEN
We demonstrate mechanisms by which HIV-1 appears to facilitate its own infection in ex vivo-infected human lymphoid tissue. In this system, HIV-1 readily infects various CD4+ T cells, but productive viral infection was supported predominantly by activated T cells expressing either CD25 or HLA-DR or both (CD25/HLA-DR) but not other activation markers: There was a strong positive correlation (r=0.64, P=.001) between virus production and the number of CD25+/HLA-DR+ T cells. HIV-1 infection of lymphoid tissue was associated with activation of both HIV-1-infected and uninfected (bystanders) T cells. In these tissues, apoptosis was selectively increased in T cells expressing CD25/HLA-DR and p24gag but not in cells expressing either of these markers alone. In the course of HIV-1 infection, there was a significant increase in the number of activated (CD25+/HLA-DR+) T cells both infected and uninfected (bystander). By inducing T cells to express particular markers of activation that create new targets for infection, HIV-1 generates in ex vivo lymphoid tissues a vicious destructive circle of activation and infection. In vivo, such self-perpetuating cycle could contribute to HIV-1 disease.
Asunto(s)
Efecto Espectador/inmunología , Linfocitos T CD4-Positivos/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Activación de Linfocitos/inmunología , Tejido Linfoide/inmunología , Linfocitos T CD4-Positivos/virología , Células Cultivadas , Regulación Viral de la Expresión Génica/inmunología , Proteína p24 del Núcleo del VIH/inmunología , Infecciones por VIH/terapia , VIH-1/patogenicidad , Antígenos HLA-DR/inmunología , Humanos , Subunidad alfa del Receptor de Interleucina-2/inmunología , Tejido Linfoide/virologíaRESUMEN
Trata-se de paciente no limiar da idade senil, com diagnóstico recente de Leucemia Mielóide Crônica e instabilidade hemodinâmica de difícil tratamento. Embora tivesse outras doenças que pudessem explicar estas manifestaçSes, como miocardiopatia chagásica e insuficiência cardíaca congestiva, foi necessário buscar novas possibilidades diagnósticas. O objetivo do tratamento é evidenciar a importância de buscar novas hipóteses, baseando-se na lógica e raciocínio clínico. Usar com discernimento a propedêutica complementar. Estar pronto para reconhecer erros e mudar condutas. Tudo isso para proporcionar o melhor atendimento, evitando agressSes e riscos desnecessários ao paciente.