The production of collagenase by adherent mononuclear cells cultured from human peripheral blood

Abstract

Mononuclear cells were isolated from human peripheral blood by Ficoll-Hypaque centrifugation, and the cells adherent to plastic substrata were cultured in serum-free media supplemented with lactalbumin hydrolysate. These cell cultures, which consisted predominantly of monocyte-macrophages as judged by nonspecific esterase staining, accumulated collagenase in the medium. This collagenase resembled other vertebrate collagenases in that it cleaved native triple-helical type I collagen at a locus Y4-length away from the aminoterminal end of the molecule. The collagenase activity was inhibited by Na2EDTA, dithiothreitol, and fetal calf serum, while the addition of Ca++ or N-ethylmaleimide enhanced the enzyme activity. 1984. collagenase in the culture media was markedly enhanced by the incubation of cells with concanavalin A or phorbol myristic acetate. In the presence of cycloheximide, the levels of collagenase activity were markedly reduced, suggesting that active protein synthesis was required to express the enzyme activity. In additional experiments, monocytes were further purified by counterflow centrifugation-elutriation. The collagenase production was markedly increased in cultures enriched in monocyte-macrophages and devoid of polymorphonuclear leukocytes. The accumulation of collagenase in monocyte cultures incubated for 48 hours in the presence of concanavalin A or phorbol myristic acetate was of the same order of magnitude as in parallel cultures containing the same number of polymorphonuclear leukocytes purified by Ficoll-Hypaque centrifugation and Plasmagel sedimentation. The demonstration of collagenase activity in the monocyte cultures appears to reflect the increased diversity of monocyte functions which may play an important role in the tissue damage in chronic inflammatory diseases such as rheumatoid arthritis.In recent years, the monocyte-macrophage, the hallmark of chronic inflammatory cell infiltrates, has been found to possess an increased repertoire of secretory functions ( 1,2). Macrophages recovered from peritoneal exudate (3,4), pulmonary alveolar fluid (5,6), and tumor cell lines (7) have been found to secrete collagenase, as well as other proteolytic enzymes thought to mediate the degradation of connective tissue matrices (8). In this study, we have investigated collagenase production by monocyte cultures established from human peripheral blood. Because monocytes are precursors of tissue macrophages within rheumatoid and other chronic inflammatory lesions,

Attenuated liver tumor formation in the absence of CCR2 with a concomitant reduction in the accumulation of hepatic stellate cells, macrophages and neovascularization

“…49,50 Moreover, CCR2 was expressed by intratumoral F4/80-positive macrophages, which can secrete various angiogenc factors and MMP, including bFGF and MMP9. [42][43][44]51 CCR2 deficiency resulted in the reduction in bFGF and MMP9 gene expression marginally but not significantly, with a concomitant apparent reduction in macrophage infiltration. Thus, in this model, CCR2-mediated signals induced the accumulation of macrophages, which can contribute to neovascularization by secreting these factors, in concert with MMP2 expressed mainly by HSCs.…”

Expression of a metalloproteinase that degrades native type V collagen and denatured collagens by cultured human alveolar macrophages.

“…Louie et al (38) demonstrated interstitial collagenase activity in the media of peripheral blood monocyte cultures after 3 d of in vitro differentiation that could be upregulated by the addition of phorbol myristic acetate or concanavalin A. In contrast, Gadek et al (39) reported that collagenase activity in cultures of human alveolar macrophages was expressed in a constitutive manner.…”

12-o-Tetradecanoyl-phorbol-13-acetate-differentiated U937 cells express a macrophage-like profile of neutral proteinases. High levels of secreted collagenase and collagenase inhibitor accompany low levels of intracellular elastase and cathepsin G.

“…Among their activities potentially involved in such remodeling is production of collagenase, the enzyme that initiates the cleavage of native collagen (36) and of inhibitory molecules that specifically block this enzyme's catalytic function. A number of studies have demonstrated the release of collagenase activity from animal mononuclear phagocytes (37,38) and recently these observations have been extended to human peripheral blood monocytes (39) and alveolar macrophages (7) in culture. The production of both collagenase and collagenase inhibitor proteins by alveolar macrophages (7) and by TPA-differentiated U937 cells provide conclusive evidence that human mononuclear phagocytes can directly modulate the turnover of collagen.…”