Effect of Glucocorticoids and Catecholamines on Macrophage Antimicrobial Activity

The overall objective of this project is to establish whether glucocorticoids the catecholamines can direct modulate macrophage (MO) antimicrobial activity. The effects of glucocorticoids on resident peritoneal macrophages (MO) were determined. First a serum-free, chemically defined medium which supported resident peritoneal MO in culture for 72 hours was selected HL-1 (Ventrex, Inc.) supported MO adherence, cell number, ectoenzyme phenotype, and allowed determination of intrinsic antiviral activity of MO. Neither hydrocortisone mor dexamethasone altered the alkaline phosphodiesterase activity of the MO; however, dexamethasone (10-9 M) resulted in depressed 5'Nucleotidase activity of resident MO after 24 hours in culture. Hydrocortisone (10-6M) resulted in a transient depression in 5'N activity. Neither dexamethasone nor methylprednisolone altered MO intrinsic resistance to herpes simplex virus type I. Keywords: Macrophages; Glucocorticoids; Hydrocortisone; Dexamethasone; Herpes simplex virus; Ectoenzymes; Methylprednisolone.