Immunoglobulin-Synthesis And Gene Rearrangement In Ataxia-Telangiectasia B-Lymphoblastoid Cell-Lines

We have analysed the surface immunoglobulins, cell supernatant immunoglobulins and rearrangement of genes specifying these markers in Epstein-Barr virus-transformed lymphoblastoid cell lines, produced from normal individuals and patients with the genetic disorder ataxia-telangiectasia (A-T). Surface IgG and IgM were detected in both normals and A-T patients, while IgA was only present in the controls at a low level. Cell supernatant IgG or IgM was present in controls and some A-T patients, but the majority of A-T patients had both present. No IgA was detected in supernatants from either cell type. All of the cell lines studied showed rearrangement of immunoglobulin heavy chain genes and expression of mRNA. The results described here demonstrate that reduced IgA is not confined to A-T cells and they do not reflect the low levels of serum IgA in A-T patients.