SIMULTANEOUS DETECTION OF BETA-GALACTOSIDASE ACTIVITY AND SURFACE-ANTIGEN EXPRESSION IN VIABLE HEMATOPOIETIC-CELLS

The quantitation of intracellular beta-galactosidase activity has been described for viable cells. By using the fluorogenic substrate fluore scein-di-beta-D-galactopyranoside (FDG) in conjunction with flow cytom etry, the proportion of positive cells as well as the level of express ion can be determined. In this paper we describe beta-galactosidase ex pression in lymphoid and myeloid cells from transgenic mice that widel y express beta-galactosidase from an inserted lacZ transgene. Both foe tal and adult haematopoietic tissues are able to express beta-galactos idase. The intracellular fluorescence reflecting beta-galactosidase ac tivity can be readily combined with fluorescently labelled antibodies against cell surface antigens. Thus, beta-galactosidase can be used as a marker in transplantation experiments to study the development of l ymphoid and myeloid precursor cells. (C) 1994 Wiley-Liss, Inc.