Enzyme Inhibitory Assay Using Monoclonal Antibody against Acid α-D-Glucosidase in Prenatal Diagnosis to Identify Homozygotes of Pompe's Disease

以抗酸性阿爾發－右旋－解苷酶單株抗體作酶抑制測定可用於産前確認龐佩氏病純合子

魏季櫻(Chi-Ying Wei) ； 葉光芃(Guang-Perng Yeh) ； 陳秀鳳(Hsiu-Feng Chen) ； 王齡玉(Ling-Yue Wang) ； 林清淵(Ching-Yuang Lin)

《Acta Paediatrica Sinica》 33卷2期 (1992/04) Pp. 104-111

摘要

A From January 1985 to January 1990, measurements of acid α-Dglucosidase activity in amniocytes or chorionic villus samplings were done for 24 pregnant mothers who were carriers of Pompe's disease. 6 women had two subsequent pregnancies. Amniotic fluid was obtained by transabdominal amniocentesis performed on 10 of them, while chorionic villus samplings were obtained in the other 20. The results showed that 7(23.3%) cases were homozygotes, 16(53.4%) cases were heterozygotes, and 7(23.3%) cases were normal. Pregnancies were terminated in the homozygotic group. Final diagnosis was confirmed by either skin fibroblast culture or clinical course. However, we found that there was overlap in the acid α-D-glucosidase activity of amniocytes between homozygotes and heterozygotes due to residual activity of neutral α-D-glucosidase. In an attempt to identify heterozygotes for Pompe's disease, we established an enzyme inhibitory assay using manoclonal antibody (mAb) against acid α-D-glucosidase. Comparing the differences in a-D-glucosidase activity before and after mAb treatment the homozygotes were significantly lower than heterozygotes (P＜0.001). There was no more overlap in the difference of acid α-D-glucosidase activity before and after mAb treatment between heterozygotes and homozygotes in amniocytes. This modified enzyme inhibitory assay should facilitate homozygote detection. Comparing acid α-D-glucosidase activity between CVS and amniocytes, the enzyme activity in CVS is about 5 times higher than in amniocytes. There was no overlap in the acid α-D-glucosidase activity between homozygotes and heterozygotes. Therefore, CVS is better than amniocentesis in the prenatal diagnosis of Pompe's disease.

並列摘要

A From January 1985 to January 1990, measurements of acid α-Dglucosidase activity in amniocytes or chorionic villus samplings were done for 24 pregnant mothers who were carriers of Pompe's disease. 6 women had two subsequent pregnancies. Amniotic fluid was obtained by transabdominal amniocentesis performed on 10 of them, while chorionic villus samplings were obtained in the other 20. The results showed that 7(23.3%) cases were homozygotes, 16(53.4%) cases were heterozygotes, and 7(23.3%) cases were normal. Pregnancies were terminated in the homozygotic group. Final diagnosis was confirmed by either skin fibroblast culture or clinical course. However, we found that there was overlap in the acid α-D-glucosidase activity of amniocytes between homozygotes and heterozygotes due to residual activity of neutral α-D-glucosidase. In an attempt to identify heterozygotes for Pompe's disease, we established an enzyme inhibitory assay using manoclonal antibody (mAb) against acid α-D-glucosidase. Comparing the differences in a-D-glucosidase activity before and after mAb treatment the homozygotes were significantly lower than heterozygotes (P＜0.001). There was no more overlap in the difference of acid α-D-glucosidase activity before and after mAb treatment between heterozygotes and homozygotes in amniocytes. This modified enzyme inhibitory assay should facilitate homozygote detection. Comparing acid α-D-glucosidase activity between CVS and amniocytes, the enzyme activity in CVS is about 5 times higher than in amniocytes. There was no overlap in the acid α-D-glucosidase activity between homozygotes and heterozygotes. Therefore, CVS is better than amniocentesis in the prenatal diagnosis of Pompe's disease.

並列關鍵字

Pompe's disease ； acid a-D-glucosidase ； amniocentesis ； chorionic villi sampling