Impairment of B-cell functions during HIV-1 infection.

A variety of B-cell dysfunctions are manifested during HIV-1 infection, as reported early during the HIV-1 epidemic. It is not unusual that the pathogenic mechanisms presented to elucidate impairment of B-cell responses during HIV-1 infection focus on the impact of reduced T-cell numbers and functions, and lack of germinal center formation in lymphoid tissues. To our understanding, however, perturbation of B-cell phenotype and function during HIV-1 infection may begin at several different B-cell developmental stages. These impairments can be mediated by intrinsic B-cell defects as well as by the lack of proper T-cell help. In this review, we will highlight some of the pathways and molecular interactions leading to B-cell impairment prior to germinal center formation and B-cell activation mediated through the B-cell receptor in response to HIV-1 antigens. Recent studies indicate a regulatory role for B cells on T-cell biology and immune responses. We will discuss some of these novel findings and how these regulatory mechanisms could potentially be affected by the intrinsic defects of B cells taking place during HIV-1 infection.