EXPRESSION OF A RECOMBINANT SHEEP IGE GENE

An ovine cosmid library was screened with a bovine C epsilon gene prob e. IgE and IgA constant region genes (C epsilon and C alpha respective ly) were isolated within a single 26 kb cosmid insert. The C epsilon g ene was cloned into an expression vector which contained the rearrange d VDJ genomic segment encoding an anti-(4-hydroxy-3-iodo-5-nitrophenyl ) acetic acid (anti-NIP) VH chain. This chimeric construct was transfe cted into murine hybridoma cells producing L chain with anti-NIP antib ody specificity and stable transfectomas secreting chimeric ovine-muri ne IgE anti-NIP antibodies were obtained. Chimeric antibody, affinity purified from culture supernatants of transfected cells on a NIP-sepha rose column, was characterised by SDS-PAGE and shown to contain H and L chains of expected size. These experiments demonstrated the power of advanced molecular genetic techniques to generate immunological reage nts against low abundance immunoglobulin isotypes thus facilitating mo noclonal antibody production for further immunological studies.