Il virus insufficiente...
Come potete leggere, la deplezione dei CD4 non è affatto sufficiente a indurre una sindrome da immunodeficienza. Come continuo a ripetere da anni, i virus linfotropi non possono determinare nessun tipo di situazione così drammatica da determinare la morte per infezioni opportuniste. Nello studio si evidenzia che i sieropositivi possono vivere tranquillamente senza problemi, come accade nelle scimmie SIV+. E accade anche nei gatti FIV+... Gli sconvolgimenti del sistema immunitario che inducono immunodepressione grave sono ben altri. Il virus è lì, e non fa niente a nessuno. Buona lettura...
http://www.ncbi.nlm.nih.gov/pubmed/17709519
http://www.ncbi.nlm.nih.gov/pubmed/17709519
J Immunol. 2007 Sep 1;179(5):3047-56.
Virally induced CD4+ T cell depletion is not sufficient to induce AIDS in a natural host.
Milush JM1, Reeves JD, Gordon SN, Zhou D, Muthukumar A, Kosub DA, Chacko E, Giavedoni LD, Ibegbu CC, Cole KS, Miamidian JL, Paiardini M, Barry AP,Staprans SI, Silvestri G, Sodora DL.
Abstract
Peripheral blood CD4+ T cell counts are a key measure for assessing disease progression and need for antiretroviral therapy in HIV-infected patients. More recently, studies have demonstrated a dramatic depletion of mucosal CD4+ T cells during acute infection that is maintained during chronic pathogenic HIV as well as SIV infection. A different clinical disease course is observed during the infection of natural hosts of SIV infection, such as sooty mangabeys (Cercocebus atys), which typically do not progress to AIDS. Previous studies have determined that SIV+ mangabeys generally maintain healthy levels of CD4+ T cells despite having viral replication comparable to HIV-infected patients. In this study, we identify the emergence of a multitropic (R5/X4/R8-using) SIV infection after 43 or 71 wk postinfection in two mangabeys that is associated with an extreme, persistent (>5.5 years), and generalized loss of CD4+ T cells (5-80 cells/microl of blood) in the absence of clinical signs of AIDS. This study demonstrates that generalized CD4+ T cell depletion from the blood and mucosal tissues is not sufficient to induce AIDS in this natural host species. Rather, AIDS pathogenesis appears to be the cumulative result of multiple aberrant immunologic parameters that include CD4+ T cell depletion, generalized immune activation, and depletion/dysfunction of non-CD4+ T cells. Therefore, these data provide a rationale for investigating multifaceted therapeutic strategies to prevent progression to AIDS, even following dramatic CD4 depletion, such that HIV+ humans can survive normal life spans analogous to what occurs naturally in SIV+ mangabeys.
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