C4 allotyping on plasma or serum: application to routine laboratories

Hum Immunol. 1988 Mar;21(3):165-71. doi: 10.1016/0198-8859(88)90068-7.


Allotypes of the fourth component of complement (C4) can be detected by electrophoresis and immunofixation after treatment of EDTA plasma with neuraminidase (NAse). We have assessed the value of additional treatment with carboxypeptidase B (CPseB). Following treatment with CPseB + NAse, each allele is resolved into a single band, permitting clear definition of overlapping bands seen following treatment with NAse alone. More importantly, C4 allotypes can be determined using stored heparinized plasma or serum. Most C4 null alleles can be assigned without requiring family studies. The approach described is suitable for routine use by tissue typing laboratories.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Carboxypeptidase B
  • Carboxypeptidases / metabolism
  • Complement C4 / genetics*
  • Complement C4 / immunology
  • Edetic Acid
  • Electrophoresis, Polyacrylamide Gel
  • Heparin
  • In Vitro Techniques
  • Isoantigens / immunology*
  • Neuraminidase / metabolism
  • Phenotype


  • Complement C4
  • Isoantigens
  • Heparin
  • Edetic Acid
  • Neuraminidase
  • Carboxypeptidases
  • Carboxypeptidase B