Density distribution profiles of T cells: TM, TG and TA cells and response patterns in autologous versus allogeneic MLRs

Correlation of disease activity and drug therapy with the autologous mixed lymphocyte reaction in rheumatoid arthritis

The response of peripheral blood lymphocytes (PBL) to autologous synovial fluid lymphocytes (SFL) from patients with rheumatoid arthritis and Reiter's syndrome was investigated in an autologous mixed lymphocyte reaction (AMLR). SFL were found to be poor responders but strong stimulators of autologous and allogeneic PBL compared with autologous PBL. The plastic-adherent (macrophage) cells from the SFL were found to be highly stimulatory to autologous PBL, particularly when the adherent cells were removed from the responding PBL. The stimulation of these PBL non-adherent cells by SFL adherent cells follows two main trends: either no stimulation, or higher stimulation than using unseparated SFL and PBL. Patients in the high stimulator group were taking non-steroidal anti-inflammatory drugs while those in the low responder group were taking, in addition, second-line drugs such as D-penicillamine or gold. Autologous serum was found to inhibit the AMLR and this is probably due to drug metabolites in patients' sera. Initial results show that the AMLR in individual patients is highly correlated, over time, with the erythrocyte sedimentation rate (ESR).

Functional relationship of human T lymphocytes, monocytes and interleukins. II. Helper requirements for phytohaemagglutinin-induced proliferation of human T-lymphocyte colony-forming cells

The different requirements of human T lymphocytes of different densities for accessory cells and helper factors (Interleukin 1 (Il-1) and Interleukin 2 (Il-2) ) in the response to phytohaemagglutinin (PHA) were investigated. Human T lymphocytes were subfractionated by discontinuous density gradient centrifugation. The various T-cell subsets were stimulated by PHA to form colonies in an agar micro-culture in the presence or absence of additional adherent cells or crude preparations of Il-1 or Il-2. The results show that the higher the density of the fractionated T lymphocytes and the lower the number of cells cultured, the greater is the number of adherent cells or the amount of helper factors required for the stimulation of colony-forming T lymphocytes. The results are consistent with the assumption that monocytes provide positive modulating activity during mitogenic stimulation of colony-forming T lymphocytes. The number of monocytes necessary for exerting an optimal modulating activity depends on the number of T cells cultured and the density of the T-cell fraction. This may reflect a distinct susceptibility of T cells of different densities to monocyte-mediated helper effects.

Density separation of chronic lymphocytic leukemia cells: low-density non-T cells are efficient stimulator cells in allogeneic and autologous mixed leukocyte reaction

Unseparated mononuclear cells and E rosette-depleted non-T cells from a majority of patients with chronic lymphocytic leukemia (CLL) were found to be weak stimulators in the allogeneic mixed-leukocyte reaction (MLR). However, a minor population (1-5%) of highly active stimulator cells could be isolated from all patients studied by buoyant density centrifugation using discontinuous gradients of Percoll. The same low-density non-T-cell fraction also stimulated autologous T-cell proliferation in the autologous mixed-leukocyte reaction (AMLR). In contrast, Percoll-separated high-density non-T cells, including the leukemic B-cell pool, were completely inactive as stimulators in AMLR. These results suggest that the presence of efficient stimulator cells among CLL mononuclear cells may be masked by the large number of nonstimulating leukemic B cells.