Connective Tissue Activating Macromolecules in Macrophage Culture Medium

Abstract

Fractions isolated by isoelectric focusing (pI values 4.6-5.3) from macrophage culture media stimulated fibroblast proliferation in vitro and increased the synthesis of sulfated glycosaminoglycans (sGAGs). Cationic fractions from macrophage culture media isolated by the same procedure (pI 10.2-10.4) enhanced secretion of collagen by fibroblasts. Two dimensional electrophoresis of non-fractionated 3H-lysine labeled macrophage media only showed incorporation of label into acidic proteins. The fractions from the pI area which increased DNA and GAG synthesis by fibroblast cultures contained three major labeled proteins with molecular weights of 15 K, 25 K and 135 K.

Epidermal growth factor increases collagen production in granulation tissue by stimulation of fibroblast proliferation and not by activation of procollagen genes

“…Fibroblast cultures were started from rat experimental granulation tissue (Jalkanen, 1981). The cells were grown in Dulbecco's modification of Eagle's medium supplemented with 10 % (v/v) fetal-calf serum.…”

Human recombinant interleukin-1 regulates cellular mRNA levels of dermatan sulphate proteoglycan core protein

“…Mononuclear-cell-and macrophage-derived factors are known to increase glycosaminoglycan production by fibroblasts (Jalkanen, 1981;Bocquet et al, 1985;Langris et al, 1987). Recent studies have suggested that this is caused by IL-I activity (Langris et al, 1987;Hamerman & Wood, 1984;Yaron et al, 1987).…”

Immunology

“…Finally, one monokine which stimulates collagenase release from fibroblasts is lost upon dialysis (Huybrechts-Godin et al, 1979) and, therefore, is probably too small to be IL-1. On the other hand, Jalkanen (1981) has described a rat monokine with a pI of 4.6-5.3 which enhances the secretion of glycosaminoglycans from fibroblasts. Although this is an appropriate pI for mouse IL-1, no IL-1 assay was reported.…”