Functional integrity of T, B, and natural killer cells in homosexual subjects with prodromata and in patients with AIDS.

We have examined the numbers of the total T (T11+) cells, T-helper (T4+) cells, T-suppressor (T8+) cells, NK cells (Leu7+), and the functional integrity of T, B, and NK cells in healthy male heterosexuals and compared the data to those obtained from AIDS patients and male homosexuals at risk. The absolute number of total T (T11+) and T-helper (T4+) cell populations were significantly reduced among most of the asymptomatic homosexual males and even more decreased in the AIDS patients. By contrast, the absolute numbers of T-suppressor cells (T8) remained virtually unaltered in the three study populations. The absolute numbers of circulating natural killer cells were similar in the controls and the homosexual subjects, but significantly reduced in the AIDS patients. Proliferative responses to T-cell mitogen (PHA) and T-cell dependent B-cell mitogen (PWM) were severely impaired in prodromal subjects and more so in the AIDS group. Response to PWM was unrelated to the total number of T-suppressor cells, but was associated with a significant decrease in T-helper cell number. Furthermore, all AIDS patients exhibited a significantly depressed NK-cell activity that could not be normalized by addition of alpha IFN or IL-2 and in most cases correlated with the reduced absolute number of NK (Leu7+) cells as well as T-helper cells (T4) and T4/T8 ratios. Three distinctive subgroups with normal (N-NK), significantly heightened (H-NK), and markedly lowered (L-NK) NK activity could be readily identified among the homosexual male population at risk. The N-NK and L-NK groups displayed marginal to no response to in vitro treatment with alpha IFN and interleukin-2. The NK-cell activity, however, in the H-NK group was moderately to strongly inhibited by inclusion of the two immunomodifiers.