Scabies mites use novel immune evasion strategy.

2004 FEB 4 - (NewsRx.com & NewsRx.net) -- Researchers describe a novel immune evasion strategy in the scabies mite Sarcoptes scabiei in a recent issue of the Journal of Investigative Dermatology.

"Parasitic infestation of the skin by the mite Sarcoptes scabiei is a significant problem worldwide, particularly in socially disadvantaged communities. A multigene family of at least 24 homologs of a serine protease allergen have been identified in S. scabiei. Surprisingly, the products of all but one of these genes are predicted to be catalytically inactive, due to mutations at a critical triad of amino acids at the active site," scientists in Australia report.

"We discuss the possibility that these genes for inactivated proteases have been conserved because they mediate a novel host defense evasion strategy that the mite has evolved as an adaptation to parasitism of the epidermis," said Deborah C. Holt and collaborators at the Queensland Institute of Medical Research, the University of Queensland, and Menzies School of Health Research. "The identification of this family, and ...