Human fetal cells. I. Mitogenic responses.

Abstract

Human fetal cells from 10 prematures and newborn infants (28--38 weeks of gestational age) and isolated or non-isolated fetal cells circulating in the blood of 9 primigravidae were studied in their ability to respond to phytohemagglutinin, pokeweed, dextran sulfate and lipopolysaccharide. An age-dependent responsiveness of fetal cells obtained from the prematures to all mitogens tested was detected as well as a clear graduation of mitogenic capacity with phytohemagglutinin to produce the highest stimulation. Though a moderate mitogenic response to lipopolysaccharide and dextran sulfate was noted in the blood cultures of the infants, LPS and in part DS transformation of fetal cells obtained from maternal blood appeared to be reduced or absent. A selective stimulation of fetal cells occurring in the circulation of primiparae sufficient for prenatal diagnosis could not be achieved with the mitogens tested. The findings suggest that fetal cells crossing to the mother are different from normal fetal lymphocytes. The present study was performed to elucidate in as quantitative a manner as possible the responses of human fetal cells to different T- and B-cell mitogens. Cells were obtained from various sources for comparing the mitogenic responses of isolated and non-isolated fetal cells. Our results demonstrate that mitogenic responses depend on the gestational age of the fetal cells, the source of the cells and on experimental conditions.