Naturally-occurring tumor-reactive autoantibodies: a monoclonal antibody from normal mice reacts with tumor cells and with DNA.
A natural IgM monoclonal antibody, 1.67, was generated from apparently healthy unstimulated BALB/c mice. This antibody reacted with L5178Y murine T cell lymphoma, with human Raji cells, and with several normal cells. Further analysis of its ligand binding capacity disclosed strong binding to single-stranded DNA (ssDNA). However, this naturally-occurring monoclonal antibody binds to different epitopes on cell membranes and on DNA than another anti-DNA monoclonal antibody (18/103/1) from human origin. This conclusion was based on competition assays. Furthermore, NOA 1.67 lacks the 16/6 idiotype expressed on the 18/103/1 antibody. The 16/6 idiotype is shared by human and mouse lupus monoclonal autoantibodies that bind simultaneously to lymphoid cells and DNA. This is a first report on a natural autoantibody that binds to malignant and to normal cell membrane(s) as well as to ssDNA. It may have regulatory functions controlling malignancy and or autoimmunity.
Smorodinsky
N I
NI
Department of Microbiology, George S. Wise Faculty of Life Science, Tel Aviv University, Israel.
Cahalon
L
L
Argov
S
S
Witz
I P
IP
Shoenfeld
Y
Y
D000818:Animals; D000974:Antibodies, Antinuclear / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000912:Antibodies, Neoplasm / Q000276:immunology*; D000918:Antibody Specificity; D002462:Cell Membrane / Q000276:immunology; D004277:DNA, Single-Stranded / Q000276:immunology*; D007113:Immunity, Innate; D007075:Immunoglobulin M / Q000276:immunology*; D007940:Leukemia L5178 / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology*; D011069:Poly I / Q000276:immunology
D000974:Antibodies, Antinuclear; D000911:Antibodies, Monoclonal; D000912:Antibodies, Neoplasm; D004277:DNA, Single-Stranded; D007075:Immunoglobulin M; D011069:Poly I