title: IgE binding reactivity of peptide fragments of Bla g 4, a major German cockroach allergen.
abstract: Cockroaches have been recognized as a major cause of asthma. Bla g 4 is one of the most important German cockroach allergens. The aim of this study is to investigate IgE reactivity to the recombinant Bla g 4 (rBla g 4) in the sera of allergic patients and identify linear IgE binding epitope. For protein expression, full-length Bla g 4 (EF202172) was divided into 5 overlapping peptide fragments (E1: aa 1-100, E2: aa 34-77, E3: aa 74-117, E4: aa 114-156, and E5: aa 153-182). The full-length and 5 peptide fragments of Bla g 4 was generated by PCR and over-expressed in E. coli BL21 (DE3). The IgE binding reactivities of the full-length and peptide fragments were measured by ELISA using 32 serum samples of cockroach allergy. The sera of 8 patients (25%) reacted with rBla g 4. Four sera (100%) showed IgE-binding reactivity to full-length and peptide fragment 4, and 2 sera (50%) reacted with peptide fragment 2. One (20%) serum reacted with peptide fragment 3. The results of ELISA using overlapping recombinant fragments indicated that the epitope region was located at amino acid sequences 34-73 and 78-113, and major IgE epitope of Bla g 4 was located at amino acid sequences 118-152 of C-terminal. B-cell epitope analysis of German cockroach allergen Bla g 4 could contribute to the strategic development of more specific and potentially efficacious immunotherapy.
authors.affiliation: Department of Environmental Medical Biology and Institute of Tropical Medicine, Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kwang Hyun
authors.initials: KH
authors.lastname: Shin
authors.forename: Kyoung Yong
authors.initials: KY
authors.lastname: Jeong
authors.forename: Chein-Soo
authors.initials: CS
authors.lastname: Hong
authors.forename: Tai-Soon
authors.initials: TS
authors.lastname: Yong
mesh_terms: D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D052179:Antigens, Plant; D002648:Child; D003058:Cockroaches / Q000276:immunology*; D018604:Epitope Mapping; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D007073:Immunoglobulin E / Q000276:immunology*; D019476:Insect Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D055815:Young Adult
chemical_list: D000485:Allergens; D052179:Antigens, Plant; C097505:Blatella germanica allergen 4; D019476:Insect Proteins; D007073:Immunoglobulin E