DEFECTIVE T CELL-FUNCTION IN ATOPIC-DERMATITIS

[摘要] The cellular immune system of 37 patients with atopic dermatitis (AD) was assessed by measuring peripheral blood T [thymus-derived] and B [bone marrow-derived] cells and the in vitro lymphocyte response to graded doses of phytohemagglutinin (PHA) (background and 6 concentrations of PHA from 100-1.6 .mu.g). These were then correlated with clinical severity, eosinophil counts and serum IgE [immunoglobulin E] levels. The IgE levels (1482 IU .+-. 252 SE of the mean), eosinophil counts (977 .+-. 143) and absolute number of B cells (958 .+-. 123) were significantly (P < 0.05) higher than in age-matched controls (70 IU .+-. 28, 182 .+-. 79 and 480 .+-. 60, respectively), and each significantly (P < 0.05) correlated with the clinical severity. Percent B lymphocytes (20 .+-. 1), percent (51 .+-. 2) and total 2357 .+-. 217) T cells did not differ from controls. Eleven patients had low percent T cells (< 40%); clinical and laboratory evaluation in these patients did not differ from the remaining 26. Lymphocytes from AD patients had higher background DNA synthesis than controls (suggestive of increased number of B cells) and significantly depressed responses at the low PHA concentrations (6.3, 3.1 and 1.6 .mu.g), which significantly correlated (P < 0.05) inversely with IgE levels. These studies suggest a subtle defect in T lymphocyte function leading to increased B cells and increased IgE production.