Our experimental model of immunological tolerance to non-reproducing antigens is based on the assumption that tolerance is caused by elimination or irreversible inactivation of lymphocytes reacting specifically with the tolerance inducing antigen, and that recovery from tolerance is due to the spontaneous maturation from the stem cells of new lymphocytes reacting with the tolerated antigen. The recovery starts, when the antigen is eliminated from the organism and does not induce tolerance in newly arising lymphocytes any more. Here we report the application of this model to the depletion of CD4+ lymphocytes in persons infected with HIV. This depletion seems to be effected either directly or indirectly by HIV products. Therefore, the dynamics of this depletion can be described by the equations characterizing the dynamics of lymphocytes exposed to tolerance inducing antigen, when HIV products are substituted for antigen. In contrast to non-replicating antigens, the concentration of HIV products increases, as the infection progresses. In consequence, the CD4+ lymphocyte depletion increases with time and its dynamics are reciprocal to those of tolerance to non-reproducing antigens, which decrease with time.