title: Immunoregulation of human natural killer cells (NK) by corticosteroids: inhibitory effect of culture supernatants.
abstract: Peripheral blood lymphocytes were separated into HNK-1+ and HNK-1- subpopulations and examined for the effects of prednisolone (PRD) on natural killer cell activities in vitro. Preculture of HNK-1+ lymphocytes with PRD (10(-6) to 10(-8) mol/L) for 72 hours resulted in a significant reduction of cytotoxic functions. When peripheral blood lymphocytes were first precultured with PRD and then separated into HNK-1+ and HNK-1- subpopulations, both could suppress the target binding and lytic activities of fresh large granular lymphocytes with the HNK-1+ cells demonstrating greater inhibition than the HNK-1- cells. Moreover, PRD-treated cells demonstrated greater suppression of target binding and cytotoxicity than identical subpopulations cultured without PRD. Culture supernatants of lymphocytes treated with 10(-6) to 10(-9) mol/L concentrations of PRD contain PRD-induced soluble suppressor factor that significantly inhibited the natural killer activity of allogeneic lymphocytes against different targets. PRD-induced soluble suppressor factor was not cytotoxic itself, and suppression was evident at various effector-to-target cell ratios. These studies indicate that in addition to being directly immunosuppressive, corticosteroids may also induce immunoregulatory lymphocytes to secrete a suppressive lymphokine.
authors.affiliation: University of Michigan, Department of Pediatrics, Ann Arbor 48109-2029.
authors.forename: M P
authors.initials: MP
authors.lastname: Nair
authors.forename: S A
authors.initials: SA
authors.lastname: Schwartz
mesh_terms: D000328:Adult; D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects*; D000943:Antigens, Differentiation; D002474:Cell-Free System; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007694:Killer Cells, Natural / Q000145:classification / Q000187:drug effects* / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects*; D008297:Male; D010641:Phenotype; D011239:Prednisolone / Q000494:pharmacology*; D013491:Suppressor Factors, Immunologic / Q000502:physiology*
chemical_list: D000943:Antigens, Differentiation; D013491:Suppressor Factors, Immunologic; D011239:Prednisolone