J. Biol. Chem., Vol. 259, Issue 20, 12844-12849, Oct, 1984
The antigen identified by a mouse monoclonal antibody raised against human renal cancer cells is the adenosine deaminase binding protein
RJ Andy, CL Finstad, LJ Old, KO Lloyd and R Kornfeld
The antigen recognized by a mouse monoclonal antibody (mAb S27) raised
against a human renal cancer cell line has been identified as the adenosine
deaminase binding protein. mAb S27 immunoprecipitates binding protein
purified from a soluble fraction of human kidney. It also recognizes the
mature 120,000-dalton membrane form of binding protein from
[35S]methionine-labeled human fibroblasts, HepG2 cells, and the renal
cancer cell line against which the antibody was raised. A rabbit polyclonal
antibody raised against purified kidney binding protein completely
precipitates mAb S27-reactive material from labeled membrane extracts. mAb
S27 does not precipitate the initially synthesized 110,000 molecular weight
precursor of binding protein in fibroblasts and recognizes only a small
portion of binding protein precursor in labeled HepG2 cells suggesting that
the antigenic determinant recognized by mAb S27 may be a post-translational
modification present on the mature form of binding protein or that mAb S27
recognizes molecules in a certain conformation. Glycopeptides derived from
purified soluble kidney binding protein or exogenously added adenosine
deaminase do not inhibit the immunoprecipitation of binding protein by mAb
S27, indicating that the mature oligosaccharide chains of binding protein
are not the determinant recognized by mAb S27 and that bound adenosine
deaminase does not mask the antigenic sites on binding protein. The fact
that monoclonal antibody S27, previously shown (Ueda, R., Ogata, S.,
Morissey, D. M., Finstad, C. L., Szkudlavek, J., Whitmore, W. F., Oettgen,
H. F., Lloyd, K. O., and Old, L. J. (1981) Proc. Natl. Acad. Sci. U. S. A.
78, 5122-5126) to detect a cell surface antigen on cultured renal cancer
cells, is directed against the adenosine deaminase binding protein confirms
and extends the earlier observation (Andy, R.J., and Kornfeld, R. (1982) J.
Biol. Chem. 257, 7922-7925) that binding protein is located on the cell
surface.