Cell-mediated cytotoxicity-supporting activity of various human gammaglobulin preparations.

Antibody activity, especially that involved in the reaction of antibody-dependent cell-mediated cytotoxicity (ADCC), of five commercially available human gammaglobulin preparations (standard, pepsin-treated, plasmin-treated, polyethylene glycol-fractionated and S-sulfonated gammaglobulin) was measured. All these gammaglobulin preparations had high titers of hemagglutination inhibition and neutralizing antibody against measles virus. In ADCC reaction, the pepsin-treated gammaglobulin preparation showed no antibody activity. The standard gammaglobulin preparation showed weak activity only when highly diluted. The remaining three preparations showed high activity. Though the S-sulfonated gammaglobulin preparation showed no activity in ADCC reaction, it showed high activity after reconversion by means of oxidation and reduction in vitro. The plasmin-treated gammaglobulin preparation showed greater activity than the polyethylene glycol-fractionated preparation of the optimal concentration. In ADCC tests using the plasmin-treated gammaglobulin preparation, K cell activity was strongly inhibited by Hg (thimerosal), while, in those using the standard gammaglobulin preparation, the activity was hardly influenced by Hg, suggesting that the low ADCC activity of the standard gammaglobulin preparation of high concentrations was due to the inhibitory effect of aggregated immunoglobulin G molecules.

Congenital alveolar rhabdomyosarcoma with multiple skin metastases. Report of a case.

A rare case of congenital alveolar rhabdomyosarcoma revealing multiple skin metastases in a female neonate is reported. At birth, a ping-pong ball-sized tumor on the neck and a tumor the size of a little finger end on the chin were noticed. Then, multiple skin tumors over the whole body occurred soon after birth. A biopsied small skin tumor was at first interpreted as being compatible with metastatic congenital neuroblastoma. However, immunohistochemical and electron microscopic findings revealed positive immunoreactivity for myoglobin in a few tumor cells and the presence of a few rhabdomyoblasts among poorly differentiated tumor cells, resulting in a final diagnosis of alveolar rhabdomyosarcoma. Therefore, it should be emphasized that in cases of round cell tumor, immunohistochemical and ultrastructural studies are imperative in order to identify the tumor and differentiate it from other forms, including rhabdomyoblastoma, neuroblastoma, Ewing's sarcoma, malignant lymphoma, and small cell carcinoma.