EFFECTS OF HCG AND BETA-HCG ON IL-2 AND SIL-2R SECRETION FROM HUMAN PERIPHERAL-BLOOD MONONUCLEAR-CELLS - A DOSE-RESPONSE STUDY IN-VITRO

The effects of human chorionic gonadotropin (hCG) as well as beta-subu nit of hCG (B-hCG) in concentrations of: 80 000/25 000; 500; 50; 5 mIU /ml on in vitro release of interleukin-2 (IL-2) and soluble interleuki n-2 receptor (sIL-2R) from resting or phytohemagglutinin (PHA) activat ed human peripheral blood mononuclear cells (PBMC) were studied. Both the interleukins were measured in supernatants of human PBMC by quanti tative sandwich enzyme immunoassay method (ELISA), We found that hCG i n the dilutions of 80 000 mIU/ml (P < 0.01) and 5 mIU/ml (P < 0.05) di minished IL-2 secretion only from PHA activated PBMC. beta-hCG in conc entrations of 5 mIU/ml (P < 0.05), 500 mIU/ml (P < 0.01) and 25 000 mI U/ml (P < 0.05) also diminished IL-2 secretion from PHA activated PBMC , and only in a dilution of 25 000 mIU/ml (P < 0.05) from resting PBMC . Simultaneously, hCG in concentration of 80 000 mIU/ml (P < 0.01) pot entiated the release of sIL-2R into supernatants from resting and PHA activated PBMC, but in concentration of 50 mIU/ml (P < 0.05) slightly depressed the secretion of IL-2 from PHA activated PBMC cultures. beta -hCG in dilution of 25 000 mIU/ml (P < 0.001) stimulated the release o f sIL-2R from resting or PHA activated PBMC. beta-hCG bad also inhibit ory effect on sIL-2R secretion from resting (in a dilution of 50 mIU/m l; P < 0.05) and PHA activated (500 mIU/ml; P < 0.01) PBMC. The inhibi tory effect of very high concentrations of hCG and beta-hCG on IL-2 se cretion together with their stimulatory effect on sIL-2R release from PBMC may be an important event during the human pregnancy and various cancers. (C) 1997 Elsevier Science B.V.