Analysis of the immunoactivator sites of parotid protein isolated from bovine parotid glands.
Parotid protein (parotin) was isolated from bovine parotid glands. To analyze the active site of parotid protein, the parotid subunit (PS) was digested by trypsin and then fractionated on a Sephadex G-25 column. Fraction A induced mainly polyclonal antibody responses and interleukin 1 (IL-1)-like activities. FrAA-1, consisting of 58 amino acids (LYILYFFQSDNEDKEKVVRQEEGEE-RITALLMNGSALKQEEWWEKEDTDDTAIVLLK) was isolated from fraction A by chromatography on QAE-Sephadex A-25 columns. FrAA-1 was found to possess IL-1-like activity. There was only 29% homology between FrAA-1 and four IL-1 molecules. When 10- and 20-residue peptides based on the amino acid sequence of FrAA-1 were synthesized, P-10.2 (TDDTAIVLLK) alone exerted an IL-1-like effect on C3H/HeJ thymocytes, whereas P-20.1 (SDNEDKEKVVRQEEGEERIT) alone elicted polyclonal IgM and IgG antibody production in human lymphocytes. These results suggest that the active sites for polyclonal B-cell activator (PBA) and IL-1-like activity have different locations in FrAA-1.
Ishizaka
S
S
Third Department of Internal Medicine, Nara Medical University, Japan.
Tsujii
T
T
D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D001665:Binding Sites; D002417:Cattle / Q000235:genetics / Q000276:immunology; D002478:Cells, Cultured; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis / Q000235:genetics; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008809:Mice, Inbred C3H; D008811:Mice, Inbred DBA; D008969:Molecular Sequence Data; D010306:Parotid Gland / Q000737:chemistry / Q000276:immunology; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000276:immunology / Q000494:pharmacology; D012471:Salivary Proteins and Peptides / Q000235:genetics / Q000276:immunology* / Q000494:pharmacology; D012689:Sequence Homology, Nucleic Acid
D007375:Interleukin-1; D010446:Peptide Fragments; D012471:Salivary Proteins and Peptides