Two chicken B cell lines resistant to ouabain for the production of chicken monoclonal antibodies.

Two chicken B cell lines, termed MuH1 and MuH4, which are resistant to ouabain, were established as fusion partners for production of chicken monoclonal antibody from the parental cell lines R27H1 and R27H4 which were deficient in thymidine kinase activity. The MuH1 synthesized, but did not secrete mu chain, whereas the MuH4 secreted non-specific IgM. Fusions of the MuH1 and MuH4 with spleen cells from chickens immunized with human IgG resulted in successful preparations of hybridomas secreting antibodies specific to human IgG. Transformed cells insensitive to HAT appeared in many culture wells after cell hybridizations with R27H4, but on hybridization with MuH1 or MuH4 the appearance of such unfavorable cells could be avoided by the inclusion of ouabain in HAT medium. Thus, in comparison with the R27H4 line, the MuH1 and MuH4 lines did not provide higher fusion efficiencies, but gave increased opportunities to obtain hybridomas producing specific antibodies. Among a total of eight hybridomas, four derived from HuM1 and four derived from MuH4, seven secreted both IgG and IgM, and the remaining one derived from MuH1 secreted only IgG. In all eight hybridoma lines IgG was specifically reactive to human IgG.