Association of the "major histocompatibility complex subregion" I-J determinant with bioactive glycosylation-inhibiting factor.
Murine suppressor T-cell hybridoma cells (231F1) secrete not only bioactive glycosylation-inhibiting factor (GIF) but also an inactive peptide comparable to bioactive GIF peptide in its molecular size and reactivity with anti-GIF; the amino acid sequence of the inactive peptide is identical to that of the bioactive homologue. The inactive GIF peptide in culture supernatant of both the 231F1 cells and a stable transfectant of human GIF cDNA in the murine suppressor T hybridoma selectively bound to Affi-Gel 10, whereas bioactive GIF peptides from the same sources failed to bind to the gel. The inactive cytosolic human GIF from the stable transfectant and Escherichia coli-derived recombinant human GIF also had affinity for Affi-Gel 10. Both the bioactive murine GIF peptide from the suppressor T hybridoma and bioactive recombinant human GIF from the stable transfectant bound to the anti-I-J monoclonal antibody H6 coupled to Affi-Gel. However, bioactive hGIF produced by a stable transfectant of human GIF cDNA in BMT10 cells failed to be retained in H6-coupled Affi-Gel. These results indicate that the I-J specificity is determined by the cell source of the GIF peptide and that the I-J determinant recognized by monoclonal antibody H6 does not represent a part of the primary amino acid sequence of GIF. It appears that the epitope is generated by a posttranslational modification of the peptide.
Nakano
T
T
Division of Immunobiology, La Jolla Institute for Allergy and Immunology, CA 92037, USA.
Liu
Y C
YC
Mikayama
T
T
Watarai
H
H
Taniguchi
M
M
Ishizaka
K
K
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D001665:Binding Sites; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes; D006031:Glycosylation; D000949:Histocompatibility Antigens Class II / Q000276:immunology* / Q000378:metabolism*; D006801:Humans; D006825:Hybridomas; D015151:Immunoblotting; D007700:Kinetics; D008222:Lymphokines / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D008285:Major Histocompatibility Complex; D051379:Mice; D008969:Molecular Sequence Data; D029584:Prostatic Secretory Proteins; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism; D012680:Sensitivity and Specificity; D013491:Suppressor Factors, Immunologic / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D014162:Transfection
D000911:Antibodies, Monoclonal; D000939:Epitopes; D000949:Histocompatibility Antigens Class II; C043911:I-J-antigen; D008222:Lymphokines; D029584:Prostatic Secretory Proteins; D011994:Recombinant Proteins; D013491:Suppressor Factors, Immunologic; C043076:beta-microseminoprotein; C013059:immunoglobulin-binding factors