CYTOTOXIC AND ANTITUMOR ACTIVITY OF A SOLUBLE FRACTION OF STREPTOCOCCUS PYOGENES AGAINST S180 SARCOMA CELLS

Abstract

A fraction (60F) having cytotoxic and antitumor activities was obtained from cell-free extract of group A Streptococcus pyogenes by precipitating with 50% to 60% saturated ammonium sulfate. 60F showed cytotoxic activity inhibiting the uptake of ³H-thymidine by S180 sarcoma cells and enhancing ⁵¹Cr-release from ⁵¹Cr-labeled cells. 60F showed also antitumor activity, depressing tumor growth and prolonging lives of mice bearing S180 sarcoma cells.