T cell responses during human immunodeficiency virus (hiv)-1 infection

Abstract

The defining features of the acquired immunodeficiency are the-persistent and profound selective decrease in the function as well as number of T lymphocytes of the helper/inducer subset and a possible activation of the suppressor/cytotoxic subset, as described in 1982 (Mildvan, D., U. Mathur, et al. (1982). Opportunistic infections and immune deficiency in homosexual men. Ann Intern Med 96(6 Pt 1): 700-4). Nowadays, although depletion of CD4+ T-cells remains a hallmark of Human Immunodeficiency Virus (HIV) infection, the multifactorial nature of the disease provoked by infection by HIV-1 or Simian Immunodeficiency Virus (SIV) in non-natural hosts is generally acknowledged, in that no unique immune alteration has been identified that can fully explain the plethora of dysregulation associated with the development of pathogenic HIV and SIV infection. This review will focus on what we know (or do not know) about T cell responses during HIV infection. This choice reflects the main expertise of the authors, and the major theme of this book. However, other aspects of adaptive and innate immunity should not be overlooked. Notably, HIV-specific antibodies, including neutralizing antibodies, are an important defense of the adaptive immune system, although HIV appears to quickly evade the effect of these antibodies. Recent studies have also highlighted the role of innate immunity in protection against HIV/SIV. In addition, several cellular antiretroviral restriction factors, either constitutively expressed or induced by interferons, have been identified, which provide considerable-resistance to retroviral infection. For more on these topics, we refer readers to recent reviews summarizing these crucial aspects of the virus/host interaction (Kuritzkes, D. R. and B. D. Walker (2007). HIV-1 Pathogenesis, Clinical Manifestations and Treatment. Fields Virology. D. Knipe and P. M. Howley. Philadelphia, PA, Lippincott Williams & Wilkins. 2: 2187-2214; Levy, J. A. (2007). HIV and the Pathogenesis of AIDS. Washington, D.C., ASM Press; Zwick, M. B. and D. R. Burton (2007). HIV-1 neutralization: mechanisms and relevance to vaccine design. Curr HIV Res 5(6): 608-24; Alter, G. and M. Altfeld (2009). NK cells in HIV-1 infection: evidence for their role in the control of HIV-1-infection. J Intern Med 265(1): 29-42; Neil, S. and P. Bieniasz (2009). Human immunodeficiency virus, restriction factors, and interferon. J Interferon Cytokine Res 29(9): 569-80; Stamatatos, L., L. Morris, et al. (2009). Neutralizing antibodies generated during natural HIV-1 infection: good news for an HIV-1 vaccine? Nat Med 15(8): 866-70; Strebel, K., J. Luban, et al. (2009). Human cellular-restriction factors that target HIV-1 replication. BMC Med 7: 48; Altfeld, M., L. Fadda, et al. (2011). DCs and NK cells: critical effectors in the immune response to HIV-1. Nat Rev Immunol 11(3): 176-86).