Human monocyte heterogeneity: Interleukin 1 and prostaglandin E₂ production by separate subsets

Abstract

Human peripheral blood monocytes were separated into four different subpopulations by means of a discontinuous bovine serum albumin gradient. Of the least dense population, 7% were present in fraction A, 11% in fraction B, 28% in fraction C and of the most dense, 34% were in fraction D. The rest (17%) of the recovered cells sedimented as a pellet, of which 95% were dead. The monocytes of fraction D (= greater than or equal to 1.075 kg/l) were major interleukin 1 (IL 1) producers and their presence enhanced immunoglobulin synthesis in vitro. Fraction C (= greater than or equal to 1.070 kg/l) were the major prostaglandin E2 (PGE2) producers and demonstrated suppressor activity on in vitro IgG and IgM synthesis. Fractions A and B had minimal production of either IL 1 or PGE2 and lesser effects on the IgG and IgM synthesis. These data demonstrate functional heterogeneity of peripheral blood monocytes with respect to production of both IL 1 and PGE2 as well as accessory cells for immunoglobulin synthesis.

DIFFERENTIAL EXPRESSION OF FUNCTION‐RELATED ANTIGENS ON NEWBORN AND ADULT MONOCYTE SUBPOPULATIONS

“…This hypothesis is strengthened by various reports demonstrating subpopulations of monocytes which differ in the amounts of pro-inflammatory effector molecules including cytokines and prostaglandin E 2 (PGE 2 ), which they produce. [1][2][3][4][5] The CD14 antigen is a 55 000 mol. wt.…”

Monocyte heterogeneity in angiotensin-converting enzyme induction mediated by autologous T lymphocytes

“…Functional and phenotypic heterogeneity among density-defined subpopulations of monocytes is a well-recognized phenomenon. Differences in PGE secretion [28,29], IL-1 and other cytokine production [30][31][32][33], superoxide formation [32], and Fc receptor expression [34] have all been reported. Since monocytes increase in size and decrease in buoyant density as they mature in vitro [35], functional or phenotypic differences in density-defined subpopulations are often attributed to differences in the maturational state of the cell.…”

Effects of dietary restriction on cellular immunity in rats.

“…2, 3, and 4, respectively. The different results between IL-1 and PGE2 might be explained by the reports of Khansari et al (17), Kunkel et al (18), and Hayari et al (19). They found that IL-1 and PGE2 could be produced from separate subsets of monocytes or macrophages, and that production of IL-1 by AM was inhibited by the addition of exogenous PGE2.…”