Antigenic and enzymatic changes in infected and transformed human diploid cells.

Human diploid fibroblasts, WI-38, were infected with various agents and the levels of lysosomal enzymes determined by immunochemical quantitation. Esterase levels were raised by mumps virus and Toxoplasma gondii infection. The concentration of beta-D-glucuronidase was reduced by these same agents. Beta-D-N-acetyl glucosaminidase was greatly increased in cultures infected with T. gondii and decreased by mycoplasma infection. Two cultures transformed by SV40 showed reduced levels of esterase compared with WI-38, as did one of two transformed amnion cultures. A second amnion culture and a culture of transformed Detroit 551 fibroblasts were unchanged. The levels of acid phosphatase were sharply reduced in three of the four SV40 transformed cultures tested.