HUMAN POLYMORPHONUCLEAR LEUKOCYTES DERIVED FROM CHRONICALLY INFLAMED TISSUE EXPRESS INFLAMMATORY CYTOKINES IN-VIVO

In this study, we sought to determine if human polymorphonuclear leuko cytes (PMNs) derived from chronically inflamed tissues can produce inf lammatory cytokines in vivo. Human gingival crevicular fluid (GCF) wit h adult periodontitis was collected, and PMNs in GCF were examined aft er purified by Ficoll-Hypaque gradient method. Cytokines from peripher al blood (PB) cells stimulated with concanavalin A, LPS, or zymosan we re also characterized, since GCF contains predominantly PMNs (> 95%) w ith a small number of lymphocytes or macrophages. Production of interl eukin-1 alpha (IL-1 alpha), IL-1 beta, tumor necrosis factor-alpha (TN F alpha), and IL-6 in GCF or culture supernatants of peripheral blood cells was determined by ELISA. Significant levels of IL-1 alpha and IL -1 beta secretion were found in GCF. PB cells in culture showed promin ent cytokine production from monocytes/macrophages, followed by lympho cytes. Human peripheral blood PMNs (PB-PMNs) also produced low levels of IL-1 alpha and IL-1 beta, but not TNF alpha and IL-6. These cells w ere also examined for cytokine mRNA expression using the reverse trans cription-polymerase chain reaction analysis. Highly purified PMNs (> 9 9.5%) from GCF expressed mRNA for IL-1 alpha, IL-1 beta and TNF alpha, but not for IL-6. PB-PMNs in culture also showed mRNA expression for IL-1 alpha, IL-1 beta, and TNF alpha in a time- and dose-dependent man ner, especially after stimulation with zymosan. Therefore, we conclude d that human PMNs from inflamed tissues can produce IL-1 alpha, IL-1 b eta, and TNF alpha in vivo, but not IL-6. (C) 1994 Academic Press, Inc .