Histological and immunohistochemical investigations of hydroxyethyl-starch deposits in rat tissues

Tissue storage of hydroxyethyl starch (HES), a widely used artificial colloid, has been reported. In order to clarify whether storage of HES can be detected in tissues by immunohistochemical methods, use was made of a polyclonal rabbit anti-HES antiserum. Thirteen days after a single intravenous injection of HES rats were sacrificed and liver, spleen, lymph node, lung, kidney and skin were removed. On paraffin sections in all organs the anti-HES antiserum stained mainly cells which could be attributed to the mononuclear phagocyte system, as confirmed by the use of the antimacrophage monoclonal antibody ED1. The use of a polyclonal anti-HES antiserum may allow analysis of long-term storage and possible side effects in various tissues of man.