| Budget Amount *help |
¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 2002: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 2001: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2000: ¥1,400,000 (Direct Cost: ¥1,400,000)
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| Research Abstract |
Ovalbumin (OVA) and ovomucoid (OM) are major allergens of hen's egg white and often induce hypersensitivity in atopic children. The sequence homology of Japanese quail (JQ) egg OVA^<1)> or OM^<2)> and hen (H) egg OVA^<3)> or OM^<4)> is 88.9% or 75.8% respectively. But the binding activities of JQ-OVA to rabbit anti H-OVA serum and JQ-OM to anti H-OM serum, measured by the method of inhibition ELISA, were 6.8% and 0.04% respectively. These results indicate that the antigenicity decreases dramatically when a few amino acid residues replace each other. This study aimed to characterize the antigenic determinants of JQ-OVA by immunoblotting and microsequence analysis methods. For this purpose, JQ-OVA was isolated from the JQ egg white by the fractionation with ammonium sulfate and gel filtration chromatography. The rabbit anti JQ-OVA serum was prepared by injecting the purified JQ-OVA to a female rabbit. JQ-OVA was digested with S. aureus V8 protease, TPCK-trypsin, TLCK-chymotrypsin and pepsin, and the peptides were separated with tricine SDS-polyacrylamide gel electrophoresis and two-dimentional gel electrophoresis. The antigenicity was tested by binding an anti JQ-OVA rabbit IgG antibody with the peptides. It is proposed that a part of the antigenic determinant (or epitope) existed in the JQ-OVA sequences of 17-28, 72-84, 1 20-124, 132-149, 160-175, 206-211, 219-226, 233-242, 244-253 and 298-308. These epitopes differed from those of H-OVA. Furthermore, baby foods (chawan-musi, custard pudding egg bouro, and kakitama soup) were cooked with JQ-egg and H-egg. A sensory test revealed that there were no differences between these baby foods cooked with JQ-egg and H-egg. Those results will allow better treatment to be provided for the hen egg allergy.
1)Nisbet, et al. 1981 Eur. J. Biochem, 115, 335-345, 2)Kato, et al. 1987 Biochemistry, 26, 193-201
3)Mucha,et al. 1990 Nucleic Acids Res., 18, 5553. 4)Papamakos, et al. 1982 J. Ml. Biol., 158, 515-537
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