Stimulatory effects of immunoreactive growth hormone on proliferation of a human lymphocyte cell line.
Previous studies have indicated the secretion of a growth hormone-like molecule by the lymphocyte T-cell line, H9. We examined the autocrine growth-promoting effects of this T-cell derived factor. H9 conditioned medium stimulates proliferation of H9 cells themselves in a dose-dependent fashion. This growth stimulating effect could be blocked by anti-human growth hormone antiserum, but could not be simulated by addition of growth hormone only or interleukin 2 only, or a combination of both. Dexamethasone inhibited H9 growth in low nutrient culture conditions and seemed to somewhat offset the growth promoting effect of the hGH-like molecule. However, the exact role played by dexamethasone in H9 cell growth and death, as well as the exact mechanism by which the hGH-like molecule exerted its growth-promoting action, remain to be elucidated.
University of Texas Medical Branch, Department of Human Biological Chemistry and Genetics, Galveston 77555-0429.
T L
TL
Kao
W J
WJ
Meyer
D002460:Cell Line; D017077:Culture Media, Conditioned; D003907:Dexamethasone / Q000494:pharmacology; D013006:Growth Hormone / Q000276:immunology / Q000502:physiology*; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects; D015735:Mifepristone / Q000494:pharmacology; D013601:T-Lymphocytes / Q000502:physiology*
D017077:Culture Media, Conditioned; D015735:Mifepristone; D003907:Dexamethasone; D013006:Growth Hormone