MONOCYTE DIFFERENTIATION AND ACCESSORY FUNCTION - DIFFERENT EFFECTS ON THE PROLIFERATIVE RESPONSES OF AN AUTOREACTIVE T-CELL CLONE AS COMPARED TO ALLOREACTIVE OR ANTIGEN-SPECIFIC T-CELL LINES AND PRIMARY MIXEDLYMPHOCYTE-CULTURES

An autoreactive T cell clone derived from a patient with reactive arth ritis, two alloreactive T cell lines, two antigen-specific T cell line s and allogeneic resting T cells were analyzed for their responses to monocytes and macrophages derived from monocytes by in vitro different iation.?he autoreactive T cell clone strongly proliferated in response to fresh monocytes and to macrophages derived from a 7 day culture, b ut only poorly to monocytes cultured for 2 days. In contrast, alloreac tive and antigen-specific T cell lines proliferated to all stimulator cells equally well. Finally, primary mixed lymphocyte reactions could be stimulated by both fresh and 2-day cultured monocytes, but not by i n vitro derived macrophages. The impaired response of the autoreactive T cell clone to 2-day cultured monocytes could not be attributed to r educed expression of several well-defined surface molecules nor to ind uction of nonresponsiveness. Neither allogeneic monocytes nor cytokine s (IL-1, IL-2, IL-4, IL-6) could correct the defective response of the autoreactive T cell clone. However, preculture of monocytes in the pr esence of interferon-gamma, IL-1, IL-4 or IL-6 retained their stimulat ory capacity. Our interpretation of the selectively impaired response of the autoreactive T cell clone is that it most likely recognizes a d ifferentiation-dependent monocyte/macrophage-specific peptide.