Blood, 1 February 2003, Vol. 101, No. 3, pp. 903-906
HEMATOPOIESIS
Brief report
Distinguishable live erythroid and myeloid cells in 
-globin
ECFP x lysozyme EGFP mice
Susanne Heck,
Olga Ermakova,
Hiromi Iwasaki,
Koichi Akashi,
Chiao-Wang Sun,
Thomas M. Ryan,
Tim Townes, and
Thomas Graf
From the Department of Molecular and Developmental
Biology, Albert Einstein College of Medicine, Bronx, NY; the Department
of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Harvard
Medical School, Boston, MA; and the Department of Biochemistry and
Molecular Genetics, University of Alabama, Birmingham, AL.
We previously described a mouse line that contains green
myelomonocytic cells due to the knock-in of enhanced green
fluorescence protein (EGFP) into the lysozyme M
gene.1 We have now created a transgenic
line with fluorescent erythroid cells using a 
-globin locus control
region driving the enhanced cyan fluorescence protein (ECFP)
gene. These mice exhibit cyan fluorescent cells
specifically in the erythroid compartment and in
megakaryocyte-erythroid progenitors. Crossing the animals with lysozyme
EGFP mice yielded a line in which live erythroid and myeloid cells can
readily be distinguished by fluorescence microscopy and by
fluorescence-activated cell-sorter scanner. This cross allowed
unambiguous identification of unstained mixed erythroid-myeloid colonies for the first time. The new mouse lines should become useful
tools to dissect the branching between erythroid and myelomonocytic cells during in vitro differentiation of definitive multipotent progenitors.
