Production of collagen type I by mouse peritoneal macrophages

The origin and identity of the cells that accumulate and produce collagen in wound healing and in granulomatous and fibrotic processes have long remained unsettled. In this study, it was found that pure cultures of peritoneal macrophages produced hydroxy-L-proline not associated with Clq and produced detectable quantities of collagenase-digestible protein. Cultured macrophages synthesized collagen while retaining their phagocytic capacity. Immuno-blot analysis identified the collagen as Type I. This shows that macrophages have collagen-forming capacity and may be productive cells in pathologic collagen deposition.