Prospects for prenatal diagnosis of cystic fibrosis: induction of biochemical abnormalities in fibroblasts from patients with cystic fibrosis by a urinary glycoprotein.

Alkaline phosphatase activity, assayed on a per cell basis with an ultra 
micro-method, can be increased up to 7-fold in fibroblast cultures derived 
from patients with cystic fibrosis by induction with a urinary glycoprotein. 
Fibroblasts from normal and heterozygous individuals are not significantly induced. There 
is a suggestion of heterogeneity among cases as reflected in varying 
baseline alkaline phosphatase and alpha-glucosidase levels. 