Prognostic value of blood and bone marrow T-colony-forming cells (T-CFC) in patients with lymphadenopathy syndrome (LAS).

The in vitro proliferation capacity of peripheral blood committed T-cell precursors (T-CFC) from LAS patients was studied in order to define whether this parameter could be associated with transition to AIDS. In all patients a significantly (P less than 0.0001) decreased plating efficiency was detected. However, the lowest T-cell colony growth (less than 50 colonies/5 x 10(4) cells) was observed in the 23 patients who subsequently developed the full-blown disease within 150-570 days. Conversely, only one patient (n = 107) whose T-CFC generated greater than 50 colonies/5 x 10(4) cells developed AIDS after a mean follow-up of 867 days (range 120-1260 days). T-CFC from these patients displayed an impaired in vitro differentiation and self-renewal capacity which was independent of the clinical evolution of the disease. In 5 out of 12 AIDS patients, adherent cell-depletion of peripheral blood mononuclear cells (PBMC) enhanced the plating efficiency. Moreover, patients' but not normal adherent cells could inhibit normal T-cell colony growth in a dose-dependent manner. Media conditioned by patients' unstimulated adherent cells (LCM-A+p) also inhibited normal T-cell colony formation. In addition, LCM-A+p were capable of inhibiting interleukin 2-receptor (IL 2-R) expression and interleukin 2 (IL 2) production by normal mitogen-stimulated T-cells. These findings suggest that adherent cell-derived inhibitory activity(ies) could be responsible for the low T-cell colony formation observed in some AIDS patients.