Restoration of a normal level of immunoglobulin production in a hybridoma cell line following modification of the chromosomal immunoglobulin μ gene by gene replacement

Abstract

In the present investigation, we have measured the levels of IgM mRNA and protein in recombinant cell lines in which the chromosomal immunoglobulin μ gene has been modified by gene replacement (gene conversion or double reciprocal recombination) or vector integration (single reciprocal recombination) events. Our studies reveal that chromosomal immunoglobulin μ genes modified by gene replacement are expressed at wild-type levels whereas those modified by vector integration have lower levels of immunoglobulin μ gene expression. These results suggest that gene replacement may a preferred method for the construction of hybridoma and myeloma cell lines producing optimized immunoglobulins and for studies of immunoglobulin gene function.