title: Effects of cryopreservation on immune responses: VII. Freezing induced enhancement of IL-6 production in human peripheral blood mononuclear cells.
abstract: To better understand the effects of freezing on various immunocompetent cell functions, the interleukin-6 (IL-6)-producing activities of frozen peripheral blood mononuclear cells (PBMCs) from healthy subjects were determined. Frozen, lipopolysaccharide (LPS)-activated PBMCs produced significantly larger quantities of IL-6 than fresh cells. Although elimination of radiosensitive, CD8+ suppressor T cells had no significant effect on PHA-induced IL-6 production by T cells, elimination of CD4+ Leu-8+ suppressor T cell subsets resulted in a significantly enhanced IL-6 secretion. Exogenous addition of prostaglandin E-2 to frozen PBMCs and monocytes inhibited LPS-induced IL-6 production. The results suggest that functional inactivation of a subset of cryosensitive, PGE-2-secreting monocytes is associated with an increase in IL-6 production by the other subset. They also indicate that a subset of CD4+ Leu-8+ T cells might be involved in feedback inhibition of PHA-induced T cell-mediated IL-6 production. The results provide further evidence that the presence of larger quantities of IL-6 in conjunction with increased amounts of IL-1 and IL-2 secreted by the frozen cells may be responsible for the previously reported enhanced immunoglobulin-producing abilities of frozen cells from clinically healthy subjects and from patients with lung cancer.
authors.affiliation: Department of Medicine, Mount Sinai Hospital Medical Center, University of Health Sciences, Chicago Medical School, Illinois.
authors.forename: M
authors.initials: M
authors.lastname: Venkataraman
mesh_terms: D000961:Antilymphocyte Serum; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002448:Cell Adhesion; D015925:Cryopreservation; D015232:Dinoprostone / Q000494:pharmacology; D005615:Freezing; D006801:Humans; D066298:In Vitro Techniques; D015850:Interleukin-6 / Q000096:biosynthesis*; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000276:immunology* / Q000528:radiation effects; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000276:immunology; D010835:Phytohemagglutinins / Q000494:pharmacology
chemical_list: D000961:Antilymphocyte Serum; D015850:Interleukin-6; D008070:Lipopolysaccharides; D010835:Phytohemagglutinins; D015232:Dinoprostone