Effects of supernatants of peripheral blood mononuclear cells stimulated by thyroid microsomal antigen on thyrocyte HLA-dr expression in vitro.

Supernatants of 5 day cultures of peripheral blood mononuclear cells (PBMC) stimulated by thyroid microsomal antigens (TMA), and liver microsomal antigens (LMA) have been utilized to induce HLA-DR expression on human thyroid epithelial cells (TEC). The PBMC were obtained from 8 normal control persons and 13 patients with autoimmune thyroid disease (AITD) (7 Graves' disease and 6 Hashimoto's thyroiditis). The TEC HLA-DR expression was measured by an enzyme-linked immunosorbent assay (ELISA) technique. TEC HLA-DR expression was calculated as follows: (experimental optical density-control optical density) x 10(3): TEC HLA-DR index: % HLA-DR expression of IFN gamma 100 U/ml stimulation; and stimulation index (SI): TEC HLA-DR expression index induced by PBMC supernatants with antigen stimulation/TEC HLA-DR expression index induced by PBMC supernatants without antigen stimulation x 100. Supernatants without antigen stimulation from both normal control subjects and patients were able to induce TEC HLA-DR expression only minimally: 36.7 +/- 32.6 (mean +/- SD) TEC HLA-DR index for normal controls and 21.3 +/- 15.5 TEC HLA-DR index for AITD (not significant). The SI curves of both TMA and LMA were significantly different between control and AITD using two-way ANOVA test (p less than 0.01). TMA-stimulated PBMC supernatants from the patients increased TEC HLA-DR expression when compared to basal level using paired t-test; TMA 1 ng/ml, SI 179 +/- 99, less than 0.05.(ABSTRACT TRUNCATED AT 250 WORDS)