Evidence for the Separate Human T - Lymphocyte Subpopulations That Collaborate With Autologous Monocyte / Macrophages in the Elaboration of Colony - Stimulating Activity

We investigated the interaction of monocyte/macrophages and autologous T lymphocytes in the methanol extraction residue (MER) of BCG-induced production of granulocyte-macrophage colony-stimulating activity (CSA). Coincubation of monocyte/macrophages and T lymphocytes at a 1 :3 ratio produces an optimum collaboration; a change to a 1 :9 ratio diminished this collaboration. Coincubation of monocyte/macrophages and T lymphocytes primed with lithium carbonate (2 meq/liter) for 40 hr synergistically increased CSA elaboration and prevented the decline in CSA noted for the 1 :9 monocyte/macrophage:T lymphocyte ratio. In contrast. concanavalin-Aprimed T lymphocytes did not enhance CSA elaboration at any monocyte/macrophage:T lymphocyte ratio except. occasionally. at 1 :9. However, this was overcome if the