Decreased Lymphoproliferation by Peripheral Mononuclear Cells (PBMC) from Tuberculosis (TB) Patients Preincubated with Cortisol and/or Dehydroepiandrosterone (DHEA).

D'ATTILIO LUCIANO DAVID,; BOZZA VERÓNICA,; DÍDOLI GRISELDA,; BOTTASSO OSCAR,; BAY MARÍA L.

Córdoba

Congreso; VII Congreso Latinoamericano de Inmunología; 2005

Sociedad Argentina de Inmunolgía

Given the immunomodulatory effects of cortisol (Cort) and DHEA, whose levels are respectively increased and decreased, in TB patients, we analyzed whether previous treatment with Cort and/or DHEA modified the lymphoproliferative response to sonicate M.tuberculosis (ST, 8µg/ml, 5 days) or Concanavalin-A (ConA, 5µg/ml, 72 h), in TB cases (n=9) and controls (HCo, n=10). PBMC were incubated during 24 h (pre) with Cort (1 or 0.1µM) and/or DHEA (0.1, 0.01 or 0.001µM), or culture medium alone (CM). The latter cultures were also treated with steroids in simultaneous (simult) with ST- or ConA-stimulation (all cultures were stimulated). [3H]thymidine incorporation [cpmx103; median (range)] to Con A was as follows: TB [52 (15.5-121.5)], HCo [166 (161.3-188.9)], p<0.01. Compared to cultures with no hormones (CNH), treatment with Cort 1µM lowered the mitogen-driven response in HCo (p<0.01) more pronounced in pre [49.1 (30.8-62.1)] than in simult [111.5 (84.2-131.4)], p<0.01. Such an effect was not reverted by DHEA. Con-A-induced responses in TB were similar to HCo. Only 2 patients responded to ST, vs. 9/10 HCo (p=0.005). Preincubation with steroids also decreased the ST-induced responsiveness in HCo, i.e.: ST+Cort 1µM+DHEA 0.1µM, pre [0.55 [0.42-2.3)], simult [2.1 (0.8-3.4)], p<0.01; CNH: [5.1 (3.5-10.8)], p<0.01. Impaired antigen- or mitogen-driven proliferation by Cort treatment becomes clearer when PBMC are exposed previously.