Production and characterization of a monoclonal antibody specific for ubiquitin-like polypeptide responsible for nonspecific immune suppression.
Monoclonal nonspecific suppressor factor (MNSF) is a lymphokine product of a murine T cell hybridoma that inhibits the immune response in an antigen nonspecific manner. Recently, we found that a novel ubiquitin-like protein (Ubi-L), a subunit of MNSF, is responsible for its biological activity. We developed a monoclonal antibody with specific activity against Ubi-L. Inhibition experiments showed that this mAb, termed NA4, preferentially recognizes Ubi-L but not irrelevant proteins such as ubiquitin. With the use of NA4, we established an ELISA method for the quantitation of Ubi-L. By this ELISA system, approximately 40 ng/ml of MNSF was detected in the culture supernatants of concanavalin A (Con A)- or interferon gamma (IFN gamma)-activated splenocytes, whereas MNSF in the supernatant of IFN alpha- and IFN beta-stimulated splenocytes was nil. In addition, NA4 could abrogate the action of Ubi-L. Thus NA4 was confirmed to be a pertinent tool for elucidation of the underlying mechanism of action of MNSF.
Nariai
Y
Y
Department of Biochemistry, Shimane Medical University, Izumo, Japan.
Nakamura
M
M
Kondoh
T
T
Tanigawa
Y
Y
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology* / Q000494:pharmacology; D000918:Antibody Specificity / Q000276:immunology; D002455:Cell Division / Q000187:drug effects; D002999:Clone Cells / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D000939:Epitopes / Q000235:genetics / Q000276:immunology; D005982:Glutathione Transferase / Q000276:immunology; D006825:Hybridomas / Q000276:immunology; D007108:Immune Tolerance / Q000276:immunology*; D015151:Immunoblotting; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology; D010455:Peptides / Q000276:immunology*; D011994:Recombinant Proteins / Q000187:drug effects / Q000276:immunology; D012967:Sodium Dodecyl Sulfate; D013154:Spleen / Q000166:cytology; D013491:Suppressor Factors, Immunologic / Q000187:drug effects / Q000276:immunology; D014452:Ubiquitins / Q000187:drug effects / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000939:Epitopes; D010455:Peptides; D011994:Recombinant Proteins; D013491:Suppressor Factors, Immunologic; D014452:Ubiquitins; C072169:monoclonal nonspecific suppressor factor; D012967:Sodium Dodecyl Sulfate; D005982:Glutathione Transferase