GROWTH-HORMONE (GH) AND THE IMMUNE-SYSTEM - IMPAIRED PHAGOCYTIC FUNCTION IN CHILDREN WITH IDIOPATHIC GH DEFICIENCY IS CORRECTED BY TREATMENT WITH BIOSYNTHETIC GH

Thirty-seven prepubertal children evaluated for severe growth retardat ion were studied by assessment of total granulocyte, monocyte and lymp hocyte count, lymphocyte subsets CD3+, CD3+Dr+, CD3+Dr-, CD4+, CD8+, C D8+CD57+, CD8+CD57-, CD16+, CD20+ and CD23+, serum immunoglobulin conc entrations, and phagocytic activity of circulating neutrophils and mon ocytes (by a flow cytometric assay). Idiopathic GH deficiency was diag nosed in 21 of 37 patients; the remaining 16 healthy subjects served a s controls. Fourteen patients received biosynthetic GH (rhGH), and the ir immune parameters were assessed at baseline and after 6 months of t herapy. Phagocytic function mediated by both polymorphonuclears and mo nocytes was significantly impaired in GH-deficient subjects compared t o controls (p<0.003 for neutrophils, p<0.007 for monocytes), while a s ignificant increase of phagocytic activity was obtained during longter m rhGH replacement therapy (p<0.02 for neutrophils, p<0.001 for monocy tes), thus suggesting that GH may affect the functional activity of ci rculating phagocyte cells. No significant differences were found in to tal granulocyte, monocyte and lymphocyte counts, T- and B-lymphocyte s ubsets and immunoglobulin levels, between GH-deficient patients and co ntrols, and between values observed before and during rhGH substitutio n treatment.