The Journal of Immunology, Vol 151, Issue 1 92-99, Copyright © 1993 by American Association of Immunologists

ARTICLES

Characterization of CD7+CD19+ lymphoid cells after Epstein-Barr virus transformation

ER Panzer-Grumayer, S Panzer, M Wolf, O Majdic, OA Haas and JH Kersey
Children's Cancer Research Institute, St. Anna Kinderspital, Vienna, Austria.

The early stages of lymphoid differentiation preceding T and B lineage commitment remain poorly defined. We hypothesized that early lymphoid precursor cells are possibly common progenitors and would express a very early T cell-associated Ag (CD7) and a very early B cell- associated Ag (CD19) simultaneously. We therefore transformed CD7+CD19+ fetal bone marrow lymphoid cells using EBV. Extensive characterization of the resulting cell lines indicated that two cell lines corresponded to pre-B and early B cells co-expressing CD7. The third cell line resembled a thymocyte, which co-expressed a number of B cell-associated Ag including CD19 and the stem cell Ag CD34. The two predominantly B lineage cell lines have their Ig genes rearranged, whereas the predominantly T lineage cell line has TCR and Ig H chain genes rearranged. Cross-lineage Ag were not expressed any more after culturing for a prolonged period of time, i.e., B lineage cells became CD7 negative and the thymocyte lineage became negative for the B cell- associated Ag. However, in all three cell lines TCR and/or Ig gene rearrangements remained unchanged. These observations support the existence of a common lymphoid precursor co-expressing CD7 and CD19 that gives rise to either T or B cells.