Journal of Histochemistry and Cytochemistry, Vol. 50, 877-884, July 2002, Copyright © 2002, The Histochemical Society, Inc.
Detection of Pyruvate Dehydrogenase E1
-subunit Deficiencies in Females by Immunohistochemical Demonstration of Mosaicism in Cultured Fibroblasts
Margarita Y. Liba,
Ruth M. Brownc,
Garry K. Brownc,
Michael F. Marusichb, and
Roderick A. Capaldia
a Institute of Molecular Biology, Oxford, United Kingdom
b Neuroscience, Oxford, United Kingdom
c University of Oregon, Eugene, Oregon, and Department of Biochemistry, University of Oxford, Oxford, United Kingdom
Correspondence to:
Roderick A. Capaldi, Inst. of Molecular Biology, U. of Oregon, Eugene, OR 97403-1229. E-mail: rcapaldi@oregon.uoregon.edu
Deficiency of the E1
-subunit of the pyruvate dehydrogenase (PDH) complex is an X-linked inborn error of metabolism and one of the major causes of lactic acidosis in children. Although most heterozygous females manifest symptoms of the disease, it is often difficult to establish the diagnosis as results based on measurement of total PDH activity, and E1
-immunoreactive protein in patient fibroblasts may be ambiguous because of the variability in the pattern of X chromosome inactivation. We report the development of a set of monoclonal antibodies (MAbs) specific to four subunits of the PDH complex that can be used for detection of PDH E1
deficiency. We also show that anti-E1
and anti-E2 MAbs, when used in immunocytochemical analysis, can detect mosaicism in cell cultures from female patients in which as few as 25% of cells express the deficiency. This immunocytochemical approach, which is fast, reliable, and quantitative, will be particularly useful in identifying females with PDH E1
-subunit deficiency as a precursor to mutation analysis. (J Histochem Cytochem 50:877884, 2002)
Key Words:
pyruvate dehydrogenase, complex deficiency, mosaicism, X-linked pyruvate, dehydrogenase, E1
-subunit, immunocytochemical analysis