title: Humoral immune response in aged humans: suppressor effect of monocytes on spontaneous plaque forming cell generation.
abstract: In 50 old donors antibody synthesis has been detected using a protein A haemolytic plaque assay. Data provide evidence that the plaque forming cell (PFC) capacity of aged peripheral mononuclear cells (PBMC) is significantly depressed (0 . 01 greater than P greater than 0 . 001) in comparison to controls. Additionally, suppression is mediated by adherent cells, since monocyte depleted lymphocytes regain the ability of generating spontaneous plaques. The inhibitory effect of monocytes seems to be prostaglandin-dependent, since indomethacin pre-treated PBMC give rise to a normal number of plaques when compared to young mononuclear cells.
mesh_terms: D000328:Adult; D000368:Aged; D000917:Antibody Formation; D016861:Cyclooxygenase Inhibitors; D005260:Female; D006462:Hemolytic Plaque Technique; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D007370:Interferon Type I / Q000494:pharmacology; D008297:Male; D009000:Monocytes / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D016861:Cyclooxygenase Inhibitors; D007370:Interferon Type I; D007213:Indomethacin