title: Immunostimulatory effects of RACK1 pseudosubstrate in human leukocytes obtained from young and old donors.
abstract: Aims of this study were to investigate the ability of RACK1 pseudosubstrate alone or in combination with classical immune stimuli to activate human leukocytes, and to restore age-associated immune defects.A total of 25 donors (17 old donors, 77-79 yrs; 8 young donors, 25-34 yrs) were enrolled. To evaluate the effect of RACK1 pseudosubstrate on cytokine production and CD86 expression the whole blood assay was used. Cultures were treated with RACK1 pseudosubstrate in the presence or absence of lipopolysaccharide (LPS) or phytohaemagglutinin (PHA) and incubated for 24 h or 48 h for LPS-induced CD86 expression, TNF-α, IL-6, IL-8, IL-10 production, and PHA-induced IL-4, IL-10, IFN-γ, respectively. RACK1 pseudosubstrate alone induced IL-6, IL-8, and CD86 expression in both young and old donors, and IFN-γ in old donors. In combination with LPS an increase in IL-8, IL-10 and TNF-α was observed, also resulting in restoration of age-associated defective production, while no changes in the other parameters investigated were found.Even if based on a small sample size, these results suggest the possibility to by-pass some of age-associated immune alterations, which may be beneficial in situations were natural immune stimulation is required, and highlight a different role of PKCβ in immune cells activation.
authors.affiliation: Laboratory of Toxicology, DiSFeB, Università degli Studi di Milano, Milan, Italy.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Corsini
authors.affiliation: Laboratory of Toxicology, DiSFeB, Università degli Studi di Milano, Milan, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Galbiati
authors.affiliation: Department of Drug Sciences - Pharmacology, University of Pavia, Pavia, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Pinto
authors.affiliation: "Golgi Cenci" Foundation, Abbiategrasso, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Davin
authors.affiliation: "Golgi Cenci" Foundation, Abbiategrasso, Italy.
authors.forename: Letizia
authors.initials: L
authors.lastname: Polito
authors.affiliation: "Golgi Cenci" Foundation, Abbiategrasso, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Guaita
authors.affiliation: Department of Drug Sciences - Pharmacology, University of Pavia, Pavia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Racchi
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000276:immunology* / Q000378:metabolism; D051940:B7-2 Antigen / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D004731:Endotoxins / Q000494:pharmacology; D004789:Enzyme Activation; D005260:Female; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D007962:Leukocytes / Q000187:drug effects* / Q000201:enzymology / Q000276:immunology; D008297:Male; D009363:Neoplasm Proteins / Q000378:metabolism*; D010446:Peptide Fragments / Q000494:pharmacology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D064546:Protein Kinase C beta / Q000378:metabolism / Q000494:pharmacology*; D017434:Protein Structure, Tertiary; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface / Q000378:metabolism*; D013379:Substrate Specificity; D013997:Time Factors
chemical_list: D000276:Adjuvants, Immunologic; D051940:B7-2 Antigen; C497964:CD86 protein, human; D016207:Cytokines; D004731:Endotoxins; D009363:Neoplasm Proteins; D010446:Peptide Fragments; D010835:Phytohemagglutinins; C419368:RACK1 protein, human; D000075370:Receptors for Activated C Kinase; D011956:Receptors, Cell Surface; C044101:endotoxin, Escherichia coli; D064546:Protein Kinase C beta; D019204:GTP-Binding Proteins
keywords: PKC; cytokines; immunosenescence; signal transduction; whole blood assay