PT  - JOURNAL ARTICLE
AU  - Mehta, K
AU  - Claringbold, P
AU  - Lopez-Berestein, G
TI  - Suppression of macrophage cytostatic activation by serum retinoids: a possible role for transglutaminase.
DP  - 1987 Jun 01
TA  - The Journal of Immunology
PG  - 3902--3906
VI  - 138
IP  - 11
4099  - http://www.jimmunol.org/content/138/11/3902.short
4100  - http://www.jimmunol.org/content/138/11/3902.full
SO  - J. Immunol.1987 Jun 01; 138
AB  - Mouse resident peritoneal macrophages, activated in vitro with murine recombinant interferon-gamma and lipopolysaccharide in the presence of sera from different sources, showed marked differences in their abilities to inhibit murine adenocarcinoma cell growth, and in induced activity of the enzyme, tissue transglutaminase. The extraction of lipids from the serum abolished its ability to induce tissue TGase activity and to inhibit cytostatic activity, but these capabilities were fully restored by readdition of all trans-retinol or all trans-retinoic acid at physiological concentrations. Addition of dansylcadaverine, a competitive inhibitor of TGase, resulted in complete recovery of macrophages from retinoid-induced suppression of cytostatic activity. These results suggest that endogenous retinoids play an important role in the regulation of macrophage-mediated cytostatic activity in a process that is independent of prostaglandin secretion but seems to involve the protein cross-linking enzyme, tissue transglutaminase.