Turnover of lymphocytes and conceptual paradigms in HIV infection

Abstract

Prevailing views concerning the pathogenic mechanisms of AIDS have shifted from models that focus primarily on direct HIV-mediated killing of CD4+ T cells to models that emphasize the pathogenic role of generalized immune system activation. The observation that increases in T cell turnover seen in HIV-infected individuals primarily reflect increased proliferation of effector-memory T cells supports the concept that chronic immune activation plays a prominent, if not predominant, role in the pathogenesis of AIDS.

Figure 1

Turnover of specific CD4⁺ T cell subpopulations (naive versus central memory versus effector memory) during HIV infection. (a) Uninfected controls. (b) HIV-infected individuals. (c) HIV-infected HAART-treated individuals. We present this model, which integrates of the work of Hellerstein et al. (18) with concepts emerging from references cited in this Commentary, as well as research not cited because of space limitations.