Production of Cytoplasmic Azurophilic Inclusions in Connective Tissue Cells by Suspending Agents. ∗

Abstract

Comment and summary

The evidence presented indicates that various suspending agents produce characteristic changes in fibroblasts and macrophages of loose connective tissue. Similar alterations occurred in endothelial system. The azurophilic inclusions were so named because they stain with the azur component of the polychrome dyes used. The data indicate that administration of cortisone acetate in conjunction with the suspending agents tends to increase the number of affected fibroblasts in areas remote from the site of injection.

The number of azurophilic inclusions in each fibroblast and their persistence for many days following a single injection suggests that the function of this cell may be altered. This possibility should be taken into account in evaluating the action of Cortone on connective tissue reactions. Further, since the suspending agents also affect endothelial cells it is conceivable that they (as well as cortisone itself) could be responsible for modifying capillary permeability as described by Menkin 4 . Also, such agents might modify the rate of repair following traumatic or chemical injury by altering the fibroplastic activity of fibroblasts.

The alterations in the affected cells did not appear to be typically degenerative since their nuclei were not adversely affected except in the very central portion of the site of injection. The azurophilic material did not appear to be phagocytized substance but rather altered cytoplasm.

Although the presence of azurophilic inclusions has not been described by other authors, intravenous injection of polyvinylpyrrolidon for prolonged periods produced alterations in reticulo endothelial cells of spleen, lymph nodes, liver, etc., which were similar to those found in lipoid storage diseases. 5

In view of the extent and duration of the cytological alterations described here and the widespread use of suspending agents, further investigation of their possible harmful tissue effects should be pursued.