Characterization of two mouse myeloma X sheep lymphocyte cell lines secreting sheep antibody.

Two mouse X sheep interspecific cell hybrids were obtained by fusing mouse myeloma cell line Sp2/O. Ag14 with sheep lymphocytes obtained from a lymph node antigenically stimulated with azo-benzene arsonate-ovalbumin (ABA-ova). The interspecific cell lines were characterized using immunochemical, karyotypic and molecular DNA techniques. Both cell lines secreted sheep IgG1 antibody specific for the ABA haptenic determinant. Karyotypic analysis revealed that cell lines 4.11 and 11.9 had modal chromosome numbers of 91 and 106, respectively. Although C-banded spreads confirmed that fusion between sheep and mouse cells had occurred, it was not possible to differentiate sheep from mouse chromosomes. However, DNA hybridization techniques showed that each line contained sheep repetitive sequence DNA. It was calculated that cell line 11.9 contained 17640 copies while cell line 4.11 contained 734 copies of the previously characterized sheep satellite DNA.