Abstract
In a previous study (Frazieret al., 1990), it was demonstrated that two patients with type 1 (insulin-dependent) diabetes mellitus had antibodies in their serum which reacted with four 29 kDa pancreas-specific proteins on two-dimensional immunoblots. This paper reports on the purification and identification of these pancreatic proteins. The protein with the pI closest to pH7 was purified through the use of ammonium sulfate fractionation and ion-exchange chromatography. Gel filtration chromatography established that the protein's molecular weight was closer to 25 kDa. Amino acid composition and sequence analyses demonstrated homology between the protein and chymotrypsin. It is suggested that an abnormal regulation of chymotrypsin activity might be related to antibodies formed in some diabetic patients.
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Drell DW, Notkins AL: Multiple immunological abnormalities in patients with type 1 (insulin-dependent) diabetes mellitus. Diabetologia, 30: 132–143, 1987
Lendrum R, Walker G, Gamble DR: Islet-cell antibodies in juvenile diabetes mellitus of recent onset. Lancet, 1: 880–883 1975
Lernmark A, Freedman ZR, Hofman C, Rubenstein AH, Steiner DF, Jackson RL, Winter RJ, Traisman HS: Islet-cell-surface antibodies in juvenile diabetes mellitus. N Engl J Med, 299: 375–380, 1978
Baekkeskov S, Nielson JH, Marner B, Bilde T, Ludvigsson J, Lernmark A: Autoantibodies in newly diagnosed diabetic children immunoprecipitate human pancreatic islet cell proteins. Nature, 298: 167–169, 1982
Frazier JS, Oates EL, Salata KF, Jacobowitz DM: Serum autoantibodies in type 1 (insulin-dependent) diabetes mellitus: Identification of reactivity against a 29 Kd pancreas-specific protein. Applied Theoretical Electrophoresis, 1: 197–200, 1990
Bidlingmeyer BA, Cohen SA, Tarvin TL: Rapid analysis of amino acids using pre-column derivatization. J Chromat, 336: 93–104, 1984
Matsudaira P: Sequence from picomole quantities of proteins electroblotted onto polyvinylidene difluoride membranes. J Biol Chem, 262: 10035–10038, 1987
Desnuelle P: Chymotrypsin. In: Boyer PD, Lardy H, Myrback K (eds.) The Enzymes 2nd ed. Vol. IV, New York, Academic Press, 93–118, 1960
Moore WGI: Behavior of chymotrypsinogen during low pH gel electrophoresis is altered by persulfate. Biochem Biophys Acta, 870: 372–374, 1986
Bloom SA, Adrian TE, Barnes AJ, Polak JM: Autoimmunity in diabetics induced by hormonal contaminants of insulin. Lancet, 1: 14–17, 1979
Gregoire S, Bendayan M: Immunocytochemical studies of pancreatic acinar cells from spontaneously diabetic BB Wistar Rats. Pancreas, 2: 205–211, 1987
Gregoire S, Bendayan M: Immunocytochemical studies of pancreatic acinar cells in normal and streptozotocin-induced diabetic rats. Diabetologia, 29: 655–660, 1986
Coan MH, Roberts RC, Travis J: Human pancreatic enzymes. Isolation and properties of a major form of chymotrypsin. Biochemistry, 10: 2711–2717, 1971
Smillie, LB, Furka A, Nagabhushan N, Stevenson KJ, Parkes CO: Structure of chymotrypsinogen B compared with chymotrypsinogen A and trypsinogen. Nature, 218: 343–346, 1968
King CH, Gorainik CH, Kleinhenz PJ, Marino JA, Sedor JR, Mahmoud AAF: Monoclonal antibody characterization of a chymotryposin-like molecule on neutrophil membrane associated with cellular activation. J Clin Invest, 79: 1091–1098, 1987
Yamaguchi T, Fukase M, Nishikawa M, Fujimi T, Fujita T: Parathyroid hormone degradation by chymotrypsin-like endopeptidase in the opossum kidney cell. Endocrinology, 123: 2812–2817, 1988
Newlands GEI, Gibson S, Knox DP, Grencis R, Wakelin D, Miller HRP: Characterization and mast cell origin of a chymotrypsin-like proteinase isolated from intestines of mice infected with Trichinella spiralis. Immunology, 62: 629–634, 1987
Tager HS, Emdin SO, Clark JL, Steiner DF: Studies on the Conversion of Proinsulin to Insulin: II. Evidence for a chymotrypsin-like cleavage in the connecting peptide region of insulin precursors in the rat. J Biol Chem, 248: 3476–3482, 1973
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Frazier, J.S., Nakata, H. & Jacobowitz, D.M. Chymotrypsin-reactive antibodies in insulin-dependent diabetes mellitus. Mol Cell Biochem 110, 175–180 (1992). https://doi.org/10.1007/BF02454196
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DOI: https://doi.org/10.1007/BF02454196