Allergenicity of recombinant troponin C from Tyrophagus putrescentiae.
BACKGROUND
The storage mite, Tyrophagus putrescentiae, produces potent allergens, many of which have not been characterized. This study was undertaken to characterize the allergenicity of troponin C from T. putrescentiae.


METHODS
A cDNA encoding 17.7 kDa troponin C, with homology to cockroach allergen Bla g 6, was identified from T. putrescentiae-expressed sequence tags. Recombinant troponin C was expressed and IgE responses to the recombinant protein were assessed in the presence and absence of 10 mM CaCl(2). Cross-reactivity between T. putrescentiae troponin C and Bla g 6 was tested using an inhibition ELISA.


RESULTS
Recombinant T. putrescentiae troponin C shares 62.7-85.5% homology with troponin C from various arthropods. Sera from 5 of 47 subjects in our study group (10.6%) showed IgE binding to the recombinant protein. Interestingly, addition of 10 mM CaCl(2) increased the intensity of IgE binding approximately 2-fold. In an immune-inhibition ELISA with these sera, T. putrescetiae troponin C and Bla g 6 did not cross-react significantly.


CONCLUSIONS
Troponin C is a new mite allergen with calcium-dependent IgE reactivity.
Jeong
Kyoung Yong
KY
Department of Environmental Medical Biology and Institute of Tropical Medicine, Korea National Arthropods of Medical Importance Resource Bank, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Korea.
Kim
Chung-ryul
CR
Un
Sunjin
S
Yi
Myung-hee
MH
Lee
In-Yong
IY
Park
Jung Won
JW
Hong
Chein-Soo
CS
Yong
Tai-Soon
TS
D040041:Acaridae / Q000235:genetics / Q000276:immunology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000485:Allergens / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D052179:Antigens, Plant; D001483:Base Sequence; D002648:Child; D003429:Cross Reactions / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D019209:Troponin C / Q000235:genetics / Q000276:immunology*; D055815:Young Adult
D000485:Allergens; D052179:Antigens, Plant; C511810:Bla g 6 allergen, Blattella germanica; D011994:Recombinant Proteins; D019209:Troponin C; D007073:Immunoglobulin E