Immunoglobulin double-isotype expression by trans-mRNA in a human immunoglobulin transgenic mouse

摘要: Abstract We have studied immunoglobulin double-isotype expression in a transgenic mouse (TG.SA) which of the endogenous heavy chain locus is almost completely excluded by nonallelic rearranged human mu transgene. By flow-cytometric analyses, we shown that small, but significant, portion (about 4%) spleen cells expresses (transgene) and gamma (endogenous) chains when cultured vitro with bacterial lipopolysaccharide interleukin 4. using amplification cDNA polymerase reaction, followed cloning sequencing amplified fragment, demonstrated trans-mRNA consisting variable constant (gamma 1) region sequences. Such could be produced either switch recombination or trans-splicing between transgene sterile 1-gene transcripts. These results indicate might possible mechanism for normal B lymphocytes not second expressed gene.