Surface IgM on DT40 cells may be a component of the putative receptor complex responsible for the binding of infectious bursal disease virus.

To investigate the host-pathogen interactions between infectious bursal disease virus (IBDV) and target B-lymphocytic cells, a cDNA T7 phage display library from the chicken bursa of Fabricius was constructed and screened for virus binding. Surface immunoglobulin M (sIgM) was isolated as a putative candidate binding site and its interactions with IBDV were further investigated using a chicken bursal lymphoma-derived cell line DT40. The results showed that the λ light chain of sIgM specifically interacted with IBDV in a virulence-independent manner in vitro, and most of the binding of IBDV to DT40 cells was inhibited by sIgM-specific monoclonal antibodies.

[Secretable eukaryotic expression of recombinant chicken Iglambda and preparation of monoclonal antibodies against chicken Iglambda].

Aim: To construct the eukaryotic expression vector for chicken Iglambda light chain, to express it on COS7 cells and to prepare the monoclonal antibodies against chicken Iglambda.

Methods: The cDNA of chicken Iglambda light chain with signal peptide sequence was amplified and then inserted into eukaryotic expression plasmid pcDNA3 after double enzyme cutting. The constructed recombinant vector was transfected into COS7 cells by lipofectamin and the secretable eukaryotic expression of chicken Iglambda light chain was verified by Western blot.