Characterisation of Sarcoptes scabiei antigens
In pig herds, the status of Sarcoptes scabiei infections is routinely monitored by serodiagnosis. Crude antigen for ELISA is usually prepared from S. scabiei var. canis or other variations and may lead to variations in the outcome of different tests, making assay standardisation difficult. This study was performed to investigate the antigen profiles of S. scabiei, including differences between hydrophilic and more hydrophobic protein fractions, by Western blotting with sera from pigs with defined infection status. Potential cross-reactivity among S. scabiei (var. canis, suis and bovis), Dermatophagoides farinae and Tyrophagus putrescentiae was also analysed. Hydrophobic S. scabiei antigens were detectable in the range of 40–50 kDa, whilst the hydrophilic fraction showed no specific antigenicity. In the hydrophobic fractions of D. farinae and T. putrescentiae, two major protein fractions in a similar size range could be identified, but no cross-reactivity with Sarcoptes-positive sera was detectable. However, examination of the hydrophilic fractions revealed cross-reactivity between Sarcoptes-positive sera and both the house dust mite and the storage mite in the range of 115 and 28/38 kDa. Specific bands in the same range (42 and 48 kDa) could be detected in blots from hydrophobic fractions of all three tested variations of S. scabiei (var. canis, bovis and suis). These results show that there are considerable differences in mange antibody reactivity, including reactions with proteins from free-living mites, which may interfere with tests based on hydrophilic antigens. Further refinement of antigen and the use of specific hydrophobic proteins could improve ELISA performance and standardisation.
KeywordsHouse Dust House Dust Mite Scabies Positive Seron Sarcoptic Mange
The strains of the free-living mites D. farinae were a kind gift from Prof. Heinz Mehlhorn, Düsseldorf. The protein sequence determination was conducted at the Max F. Perutz Laboratories Mass Spectrometry Facility, Vienna, Austria.
- Anonymous (2006) SWISS-2DPAGE. Two-dimensional polyacrylamide gel electrophoresis database. Swiss Institute of Bioinformatics. Available at http://www.expasy.ch/ch2d/. Accessed 26 March 2010
- Beck W, Hiepe T (1997) Untersuchungen zur allergisierenden Wirkung und zum spezifischen Proteinmuster der Räudemilben Chorioptes bovis, Psoroptes ovis (Acari: Psoroptidae), Sarcoptes suis und Notoedres cati (Acari: Sarcoptidae) mit der SDS-PAGE und dem Immunoblot. Berl Münch Tierärztl Wschr 110:128–133Google Scholar
- Gafvelin G, Johansson E, Lundin A, Smith AM, Chapman MD, Benjamin DC, Derewenda U, van Hage-Hamsten M (2001) Cross-reactivity studies of a new group 2 allergen from the dust mite Glycophagus domesticus, Gly d2, and group 2 allergens from Dermatophagoides pteronyssinus, Lepidoglyphus destructor, and Tyrophagus putrescentiae with recombinant allergens. J Allergy Clin Immuol 107:511–518CrossRefGoogle Scholar
- Kuhn C (2008) Charakterisierung rekombinanter immunreaktiver Antigene der Krätzmilbe Sarcoptes scabiei. Dissertation, Humboldt University, BerlinGoogle Scholar
- Lerch S (2001) Untersuchung der antigenen Proteinfraktionen eines Sarcoptes-Milben-Extraktes durch SDS-PAGE, Immunoblot, zweidimensionale Gelelektrophorese und Sequenzanalyse. Dissertation, Freie University, BerlinGoogle Scholar
- Walton SF, Holt DC, Currie BJ, Kemp DJ (2004) Scabies: new future for a neglected disease. Adv Parasitol 57:109–376Google Scholar