Stimulation of human fetal lymphocytes by lipopolysaccharide B in culture.

Cultures of Isopaque-Ficoll-isolated lymphocytes from three human sources were compared with respect to the effect of mitogens. The cell sources were maternal blood immediately after delivery, cord blood, and blood obtained by heart puncture of 10-20-week aborted fetuses. Lipopolysaccharide B (LPS) induced incorporation of tritiated thymidine, blastic transformation, and mitotic activity in cord and fetal, but not maternal, cells. The stimulation reached a maximum on days 4-8 of culture. It was stronger than the spontaneous transformation often displayed by fetal cells. If fetal cells spontaneously occurring in the blood of pregnant women were to react in a similar way, it should be possible to selectively stimulate the fetal cells with LPS. Such transformed fetal cells could then be isolated from cultures of maternal blood samples and used for antenatal diagnosis of fetal disease.