IgE binding reactivity of peptide fragments of Bla g 4, a major German cockroach allergen.
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.
Shin
Kwang Hyun
KH
Department of Environmental Medical Biology and Institute of Tropical Medicine, Arthropods of Medical Importance Resource Bank, Yonsei University College of Medicine, Seoul, Korea.
Jeong
Kyoung Yong
KY
Hong
Chein-Soo
CS
Yong
Tai-Soon
TS
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
D000485:Allergens; D052179:Antigens, Plant; C097505:Blatella germanica allergen 4; D019476:Insect Proteins; D007073:Immunoglobulin E