title: cDNA clones encoding IgE-binding factors from a rat-mouse T-cell hybridoma.
abstract: cDNA clones encoding rodent IgE-binding factors (IgE-BF) were isolated from cDNA libraries of a rat-mouse T hybridoma that secretes IgE-suppressive factor (IgE-SF) upon incubation with rat IgE. COS7 cells transfected with two of the cDNAs expressed IgE-BF, which selectively potentiate an in vitro IgE response. IgE-BF expressed in COS7 cells are glycoproteins of approximately equal to 60 and approximately equal to 11 kDa. DNA sequence analysis of an IgE-BF cDNA revealed a 556-amino acid (62 kDa) protein coding region. The results suggest that IgE-potentiating and IgE-suppressive factors share common precursor polypeptides and that the 11-kDa IgE-BF is derived from a 60-kDa precursor.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics*; D006023:Glycoproteins / Q000235:genetics; D006825:Hybridomas / Q000276:immunology; D008222:Lymphokines / Q000235:genetics*; D051379:Mice; D029584:Prostatic Secretory Proteins; D051381:Rats; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D006023:Glycoproteins; D008222:Lymphokines; D029584:Prostatic Secretory Proteins; C043076:beta-microseminoprotein; C013059:immunoglobulin-binding factors; D004247:DNA