Immunocytochemical localization of peroxisomal beta-oxidation enzymes in human fetal liver.
In the majority of congenital peroxisomal disorders, beta-oxidation of very long chain fatty acids is deficient. We have investigated the appearance and localization of the three peroxisomal beta-oxidation enzymes in normal fetal liver (fertilization age between 5 and 18 weeks) with protein A-gold immunocytochemistry and silver enhancement for light microscopic visualization. With specificity-tested polyclonal antibodies, acyl-CoA-oxidase, bifunctional enzyme, and 3-oxoacyl-CoA thiolase were localized in the peroxisomes of the parenchymal cells, which appear as brown or black granules. In the youngest specimen, no immunopositive reaction was obtained. A weak reaction with anti-thiolase was obtained at the age of 6-7 weeks. At a fertilization age of 8 weeks, peroxisomes could be distinctly visualized after immunostaining for all three enzymes. From a staining series with anti-thiolase on simultaneously treated slides, it appears that the amount of antigen per peroxisome and the organelle size increase between the seventh and eighteenth weeks. These data should enable a more specific diagnosis in fetal liver biopsies from pregnancies at risk and after termination of pregnancy.
Espeel
M
M
Free University Brussels, Laboratory of Human Anatomy, Belgium.
Jauniaux
E
E
Hashimoto
T
T
Roels
F
F
D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000096:biosynthesis; D000102:Acetyl-CoA C-Acyltransferase / Q000096:biosynthesis; D042962:Acyl-CoA Oxidase; D004746:Enoyl-CoA Hydratase / Q000096:biosynthesis; D005333:Fetus; D005865:Gestational Age; D006801:Humans; D007150:Immunohistochemistry; D008099:Liver / Q000196:embryology / Q000201:enzymology*; D008830:Microbodies / Q000201:enzymology*; D010088:Oxidoreductases / Q000096:biosynthesis*
D010088:Oxidoreductases; D015094:3-Hydroxyacyl CoA Dehydrogenases; D042962:Acyl-CoA Oxidase; D000102:Acetyl-CoA C-Acyltransferase; D004746:Enoyl-CoA Hydratase