Abstract: Objective To study the effect of human prolactin (PRL) on total IgG and anti-dsDNA antibody production in peripheral blood mononuclear cells (PBMC) from patients with systemic lupus erythematosus (SLE). Methods PBMC from SLE patients and control subjects were cultured, with the stimulation of PRL, interleukin 2 (IL-2), interleukin 10 (IL-10) and phytohemagglutinin (PHA). ³H-thymidine (³H-TdR) incorporation assay was used to study the proliferation of PBMC. Total IgG and anti-dsDNA antibodies in the cultured supernatants were measured by enzyme-linked immunosorbent assay (ELISA) in 19 patients of SLE and in 6 control subjects. Results ①The proliferation of PBMC in vitro was enhanced by 10^-9 mol/L PRL in 19 patients of SLE. ②The production of IgG and anti-dsDNA antibodies in PBMC from 10 active SLE patients was much higher than that of 9 inactive patients (P<0.01) and that of 6 control subjects (P<0.01). ③The production of IgG and anti-dsDNA antibodies in the costimulation of anti-interneukin 2 monoclonal antibodies (anti-IL-2 mAb) plus PRL was significantly lower than that stimulated of PRL in PBMC from 19 patients; on the other hand that costimulated by IL-2 plus PRL group or PHA plus PRL group significantly higher than that only by PRL. There was not significant between IL-10 plus PRL stimulation group and PRL stimulation group. Conclusion These results suggest that PRL may increase the production of IgG, including IgG type anti-dsDNA antibodies in the PBMCs of SLE patients; and IL-2 plus PHA can enhancesuch an effect.

Key words: Lupus erythematosus, systemic, Prolactin, Immunoglobulin G, Antibodies, antinuclear