Print version ISSN 0123-9392
MONTOYA GUARIN, CARLOS JULIO; MORENO FERNANDEZ, MARÍA EUGENIA and RUGELES LOPEZ, MARÍA TERESA. Reacciones y alteraciones del sistema inmune durante la infección por el VIH-1. Infect. [online]. 2006, vol.10, n.4, pp. 250-265. ISSN 0123-9392.
The acquired immune deficiency syndrome (AIDS) is the final outcome of a chronic infection with the type 1 human immunodeficiency virus (HIV-1), and is characterized by the frequent appearance of opportunistic infections, malignant neoplasms and autoimmune diseases. Despite the CD4+ T lymphocytes have been recognized as the main target cells of HIV-1, other cells from the innate immune system are also infected by this virus, but with lower replicative capability. In most of the HIV- 1-infected individuals, an early onset of the immune response against HIV-1 controls the viral replication mainly by mechanisms dependent on effector activity of innate immunity, specific neutralizing antibodies and CD8+ cytotoxic T cells. After, and due to the selective pressure exerted by the immune system and the high mutability exhibited by HIV-1, escape viral strains appear avoiding the immune control and increasing the viral replication. In consequence, the HIV-1 infection progresses over time and generates a state of severe immunological hyper-activation which contributes to the depletion of infected and uninfected bystander cells. All these quantitative immune alterations are followed by the progressive destruction of lymphoid organs and functional deficiencies in all the effector mechanisms of the immune system, which altogether conduce to the deep state of immunodeficiency characteristic of AIDS patients. It is interesting that in some individuals the immune response against HIV-1 is able to prevent the establishment of this infection or to control the progression to AIDS, as is observed in HIV-1-exposed seronegative individuals or in a minority of HIV-1-infected, antirretroviral-naïve, but slow-progressor patients.
Keywords : HIV-1; NK cells; dendritic cells; CD4+ and CD8+ T lymphocytes; Immune hyperactivation; natural resistance.