CD44 ligation on peripheral blood polymorphonuclear cells induces interleukin-6 production.
Polymorphonuclear cells (PMNs) contribute to the initiation and progression of the immune response by mediating cytotoxicity, phagocytosis, and cytokine secretion. Because CD44 serves as a cytotoxic-triggering molecule on PMNs, it was hypothesized that it could also trigger cytokine production. In this study, the effect of anti-CD44 antibodies on interleukin-6 (IL-6) production in human PMNs was assessed. By using a reverse transcriptase-polymerase chain reaction, it was shown that PMNs stimulated with a mouse monoclonal or a rabbit polyclonal F(ab)(2) anti-CD44 transcribe IL-6 messenger RNA. A similar effect was obtained when an anti-CD44 antibody was replaced with hyaluronic acid (HA). Kinetic studies showed that anti-CD44 and HA induced IL-6 gene transcription, initiated 3 hours after stimulation, peaked between 12 and 24 hours, and disappeared after 48 hours. Analogous results were achieved when secreted IL-6 protein was measured by enzyme-linked immunosorbent assay in the PMN culture supernatants. To characterize which metabolic pathways regulated CD44-dependent IL-6 production in PMNs, an RNA polymerase inhibitor, actinomycin D, and 2 protein kinase inhibitors, such as genistein and staurosporine, were tested. Actinomycin D and genistein blocked IL-6 production, whereas staurosporine did not, suggesting that CD44-dependent IL-6 production requires gene transcription and tyrosine kinase activity. Furthermore, the relationship between CD44 and cytokines that affect PMN function, including interferon gamma (IFNgamma) and IL-2, was investigated. Without CD44 cross-linking, IFNgamma did not trigger IL-6 production. However, on CD44 cross-linking, IFNgamma produced a strong synergistic effect on IL-6 syntheses in human PMNs. (Blood. 2001;97:3621-3627)
Sconocchia
G
G
Institute of Tissue Typing and Dialysis, CNR, S. Eugenio Hospital-Clinical Surgery, Pie dell'Umanesimo, 10, 00144, Rome, Italy. g.sconocchia@rm.cnr.it
Campagnano
L
L
Adorno
D
D
Iacona
A
A
Cococcetta
N Y
NY
Boffo
V
V
Amadori
S
S
Casciani
C U
CU
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D012321:DNA-Directed RNA Polymerases / Q000037:antagonists & inhibitors; D003609:Dactinomycin / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015870:Gene Expression / Q000187:drug effects; D019833:Genistein / Q000494:pharmacology; D006801:Humans; D018960:Hyaluronan Receptors / Q000276:immunology / Q000378:metabolism*; D006820:Hyaluronic Acid / Q000494:pharmacology; D007140:Immunoglobulin Fab Fragments / Q000494:pharmacology; D007371:Interferon-gamma / Q000494:pharmacology; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000235:genetics; D007700:Kinetics; D051379:Mice; D009504:Neutrophils / Q000276:immunology*; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger / Q000032:analysis; D011817:Rabbits; D011961:Receptors, Fc / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019311:Staurosporine / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects
D000906:Antibodies; D000911:Antibodies, Monoclonal; D004791:Enzyme Inhibitors; D018960:Hyaluronan Receptors; D007140:Immunoglobulin Fab Fragments; D015850:Interleukin-6; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger; D011961:Receptors, Fc; D003609:Dactinomycin; D007371:Interferon-gamma; D006820:Hyaluronic Acid; D019833:Genistein; D012321:DNA-Directed RNA Polymerases; D019311:Staurosporine