Immunoglobulin VHfamilies and light chain isotypes in the spotted wolffish (Anarhichas minor Olafsen)

The spotted wolffish (Anarhichas minor Olafsen) is a species of the Perciformes, the most diverse and numerous order of all fish. A cDNA library from head kidney tissue was screened for immunoglobulin (Ig) heavy and light chain transcripts, and showed highest identity to Ig sequences from other perciform species. So far only one Ig class is described in spotted wolffish, but three VHfamilies were identified among the heavy chain transcripts. Highest diversity was located at the CDR3 region and demonstrates the importance of this gene element to the antibody repertoire. Two VLfamilies were identified among the light chain clones and three distinct isotypes were present. Use of polymerase chain reaction and in situ hybridisation techniques revealed individual variations in the relative expression of the three isotypes of light chains.