Reactive granular cells in sites of trauma. A cytochemical and ultrastructural study.

Abstract

Granular cells resembling the cells of true myoblastoma have been observed in various sites of previous trauma (usually surgical). They may be differentiated from myoblastoma cells in routine light microscopic sections, with simple histochemical procedures, and with electron microscopic studies. The granules are dense bodies with acid phosphatase activity (lysosomes). Most cells resemble histiocytes, but some have a prominent endoplasmic reticulum and many mitochondria. Others have basement membranes, marked surface activity, a fibrillar system with condensations resembling that in smooth muscle, glycogen and desmosomal connections. These observations suggest their derivation from multipotential cells capable of forming either fibroblasts or smooth muscle cells.