Observations on human amniotic fluid cell strains in serial culture.

Observations made on 31 amniotic fluid cell strains serially cultured until senescent are recorded. The cell strains had an average life in culture of 13-9 passages (range 3-29). The source of the amniotic fluid from which the cultures were initiated did not influence the behaviour of the cell strains. The behaviour ofthe cell strains was unrelated to the growth characteristics of the primary cultures from which they were derived. Cell strains derived from serial samples of amniotic fluid from three women were compared and their characteristics were no more related to each other than to the group as a whole. The cell types found in amniotic fluid cultures are described. The karyology of 12 of the cell strains was monitored and no significant changes from normal diploidy were seen. Possible reasons for the highly variable and unpredictable behaviour of amniotic fluid cell strains are discussed. Cultured amniotic fluid cells are now in widespread use for the antenatal diagnosis of chromosome disorders and inborn errors of metabolism An accurate knowledge of the behaviour of normal cultured amniotic fluid cell strains is therefore essential for their use in genetic studies. However, little appears to be known about the characteristics of these cells in tissue culture. It has been stated (Melancon, Lee, and Nadler, 1971) that there are at least two morphologically distinguishable cell types in amniotic fluid cell cultures-an epithelial type which cannot be subcultured more than two to five times and a fibroblast-like cell which can be cultured for more than 30 passages. On the other hand, Littlefield (1971) has said that '.. . 6 to 8 weeks of rapid culture can approach the limit of the growth potential of amniotic fluid cells.. .'. This report records observations made during the long-term culture of 31 amniotic fluid cell strains. Materials and Methods Amniotic fluids were obtained from hysterotomy specimens (HS), by amniocentesis on Rhesus iso-immunized women (RhS) and by artificial rupture of Received 5 November 1973. membranes (ARM) for the induction of labour. The primary cultures were set up as previously described (Sutherland and Bain, 1972) and subcultured according to the method of Butterworth et al (1973). The cell strains were maintained in 250-ml glass vessels with a growth surface area of 40 cm2 and regularly subcul-tured on reaching confluency, using a 1:2 subculture ratio. Throughout this study, all cell strains were cultured in Ham's F10 tissue culture medium supplemented with …