Deviations in Circulating TNFαLevels and TNFαProduction by Mononuclear Cells in Healthy Human Populations

Abstract

Objectives. Tumor necrosis factor alpha (TNFα) plays a pivotal role in the inflammatory host response. The serum-level of TNFαand the production of TNFαby lympho/monocytes, however, seem to show high individual variations. The goal of the present study was to investigate the variations and inducibility of TNFα-activity in two age-groups of healthy volunteers.Methods. Sixty elderly, healthy volunteers were studied. These persons were free of malignant diseases, and within three months, they did not have any trauma or inflammatory disease and were not taking any steroids or nonsteroid anti-inflammatory drugs. Thirty young volunteers were also included. Blood samples were taken; lympho/monocytes were separated and cultured with or without endotoxin (LPS) stimulation. Serum and culture supernatant TNFαlevels were determined by bioassay using WEHI 164 cells.Results. The results indicated significant individual variations in TNFαlevels of healthy volunteers irrespective of age. Subgroups with low, middle, and high serum TNF-levels were distinguished. In about 50% of volunteers with low serum-TNFαactivity, LPS stimulation failed to increase the TNFαproduction by isolated lympho/monocytes.Conclusion. Our data suggest a chance to select individuals with enhanced sensitivity for septic complications.