Journal of Experimental Medicine, Vol 149, 1152-1167, Copyright © 1979 by Rockefeller University Press
Friend erythroleukemia antigen. A viral antigen specified by spleen focus-forming virus and differentiation antigen controlled by the Fv-2 locus
R Risser
Serum from C57BL/6 (B6) mice hyperimmunized with NB-tropic Friend virus
complex (FV) was cytotoxic for FV-induced erythroleukemic spleen cells and
B6 Friend-murine leukemia virus (F-MuLV) lymphoma cells. Cytotoxic activity
for erythroleukemia cells remained after repeated absorption of B6 anti-FV
antiserum with Friend-Moloney-Rauscher MuLV lymphoma cells but was removed
by absorption with erythroleukemia cells induced by FV or Rauscher Vrus.
This serologic test system identified a previously unrecognized
cell-surface antigen of mouse leukemia, designated Friend Erythroleukemia
(FE) antigen to signify its appearance as a determinant of virally induced
erythroleukemic differentiation. FE antigen was not detected on 15
transplanted or primary hematopoietic neoplasms, nor was it detected on
cells infected with ecotropic, xenotropic, or dualtropic MuLV isolates in
tissue culture. Two spleen focus-forming virus (SFFV) nonproducer cells of
rats and one of mice express FE antigen in amounts comparable to primary
erythroleukemia cells. Absorption tests with FE typing serum indicated that
FE antigen was expressed on bone marrow and spleen but not thymus, lymph
node, or peripheral blood of uninfected AKR, BALB/c, DBA, and SWR mice; all
five tissues from B6 and C57L were negative. Quantitiative absorption tests
indicated that the expression of FE antigen, though much lower than on
erythroleukemic cells, was greatest on fetal liver, less on bone marrow,
and lowest on spleen from BALB and SWR mice. Treatment of BALB/c or SWR
fetal liver, bone marrow, spleen, thymus, or lymph node cells with FE
typing serum did not result in significant lysis. These observations are
consistent with the interpretation that FE antigen is expressed by a minor
cell population present in fetal liver, bone marrow, and spleen. Expression
of FE antigen, determined by absorption with bone marrow cells,
cosegregated with inheritance of the Fv-2s allele in the 17 inbred, 7
recombinant inbred, and 4 congenic mouse strains tested. In summary, the FE
antigenic system identifies a cell-surface determinant that has the
properties of a SFFV-specified antigen and hematopoietic differentiation
alloantigen controlled by the Fv-2 locus. The similarity of FE antigen to
Abelson antigen may provide insight into the pathogenic properties of
defective transforming MuLV.