IgE binding epitopes of blag 6 from german cockroach

Bla g 6,a german cockroach allergen,shows homology to muscle protein troponin c. it contains four calciumbinding domains at 20-30,56-67,96-107,and 132-143 amino acid (aa) residues,and its immunoglobulin e (ige) reactivity is dependent upon calcium ion level. however,the ige binding epitopes of bla g 6 have not been investigated. this study aimed to analyze the ige binding epitopes from the five peptide fragments of bla g 6. the full-length of three bla g 6 isoallergens (bla g 6.0101,bla g 6.0201,and bla g 6.0301) and five peptide fragments (p1: aa 1-111,p2: aa 1-95,p3: aa 33-111,p4: aa 80-151,and p5: aa 33-151) of bla g 6.0101 were generated by polymerase chain reaction (pcr) and expressed in escherichia coli. enzyme-linked immunosorbent assay (elisa) was performed on 24 patients' sera that adjusted the final concentration 10 mm of cacl2 to determine the ige activities of bla g 6. eight sera (33.3%),9 sera (37.5%),and 11 sera (45.8%) showed ige reactivity to bla g 6.0101,bla g 6.0201,and bla g 6.0301,respectively. among the sera from the positive ige reactivity,three patients' sera were selected and the ige reactivity was measured by elisa with the five peptide fragments of bla g 6. based on ige responses,one patient's serum exhibited the strongest ige reactivity. we assumed that the aa between 96-151 residues,including the calcium binding domains iii and iv,would be important for ige binding. these results may provide information that will yield safe diagnostic methods and immunotherapeutics. © 2010 bentham science publishers ltd.