CORRELATION OF ACID PHOSPHATASE ACTIVITY WITH DEGREE OF BACTERIAL INFECTION IN HELA CELLS
Acid phosphatase activity has been demonstrated in HeLa cells grown in monolayers on coverslips, using the histochemical method of Barka and Anderson. In normal interphase cells variable enzymatic activity may always be demonstrated in a juxtanuclear position. When the culture medium is inoculated with a virulent strain of Shigella flexneri 2a, a certain number of cells in invaded by the organisms. In the presence of one organism, the acid phosphatase activity of the infected cell appears to increase, but as more organisms are found in individual cells, the intensity of the cells enzymatic reaction decreases. Biochemical assays on whole cell monolayers to quantitate this decrease have failed to show a significant change in enzymatic activity between infected and control cultures, possibly due to the high percentage of cells in any culture that were not infected or infected only slightly.