Cultured amniotic fluid cells for prenatal diagnosis of lysosomal storage disorders: a methodological study

The influence of culture conditions on the ultrastructure and enzyme activities of amniotic fluid cells are reported. Morphological changes were determined as a function of the number of lysosomal-like inclusion bodies per cell, and these results correlated to the activity of beta-hexosaminidase, alpha-mannosidase, beta-glucuronidase, arylsulphatase C and 5' nucleotidase. The parameters examined were pH of the culture media, type of media, increasing cell passage and day of harvest. Our results indicate that enzyme activities are less sensitive to changes in culture conditions as compared to ultrastructural changes. We therefore recommend that in order to obtain reliable ultrastructural results for the diagnosis of storage disorders, cultures should be grown in MEM as the culture medium, the pH of the medium carefully monitored to remain below pH 7.4, examining the cultures no later than the eighth cell passage and no later than the 10th day after subculture.