In the sera of 20 patients with radiographically diagnosed 3rd degree osteoporosis (type I-post menopausal, type II-of elderly age) concentrations of soluble HLA-class I antigens were determined. In these patients, HLA-ABC phenotypes were first identified, then levels of sHLA-I were determined in a semiquantitative test of lymphocytotoxic reaction inhibition according to Tait et al. and McLean et al. with our modification. Varying sHLA-I concentrations were obtained for the majority of examined HLA specificities encoded by HLA-A, B and C loci in these patients. The results were compared with similar measurements in a control population of 205 healthy unrelated adults. A statistically significant difference was shown for HLA-B27 and HLA-B44 .

Keywords: soluble HLA antigens, sHLA, Osteoporosis