This disparity could be attributed to lack of sensitivity with the assays or related CH5424802 nmr to the timing of blood collection, disease progression or other unknown factors causing an immune response in the host. However, as for IgG levels, measurement of total serum IgE appears to be of no benefit in the preliminary clinical investigation into a suspected host. Conversely, dramatic increases in total IgE levels have been documented for crusted scabies (4,27,33,34). Roberts et al. (3) document 96% of 52 cases with elevated IgE, with 73% 10× above normal levels, and 10% 100× above normal levels. Immunoblotting studies demonstrated that sera from patients
with crusted scabies showed strong IgE binding to 21 unidentified S. scabiei var. canis proteins in comparison with ordinary scabies in which only six proteins were weakly recognized (35). Studies using S. scabiei
var. canis whole mite extract to measure scabies-specific IgE binding observed elevated levels in approximately 50% of patients with active ordinary scabies (36). Recent serology results using S. scabiei var hominis recombinant proteins indicate patients with both crusted scabies and ordinary scabies have a defined IgE and IgG4 response to a number of scabies mite recombinant antigens (Walton S.F., unpublished data). Significantly greater IgE binding to a number of these proteins was observed in the sera of patients with crusted scabies compared with ordinary scabies and control groups, and similarly significantly BVD-523 molecular weight increased IgE binding of the sera of patient with ordinary scabies was observed compared with control sera. Immunohistochemistry MycoClean Mycoplasma Removal Kit staining of mite-infested skin biopsies from patients with crusted scabies has shown human IgG and IgE localizing in the mite gut and flooding the mite burrow (37) (Walton S.F., unpublished data).
In addition, polyclonal antibody to multiple S. scabiei var. hominis recombinant proteins has been demonstrated binding to the gut, external cuticle and burrow of the scabies mite (9,38) (Walton S.F., unpublished data). Immediate wheal reactions have been elicited by intradermal injection of scabies mite extracts in patients with both ordinary scabies and crusted scabies but not normal volunteers (39,40). This response was observed to wane with time, and patients injected 15–24 months after infestation did not react. IgE antibody to allergens induces early allergen-specific mast cell degranulation and contributes to the late-phase reactions by chronic tissue damage via the downstream effect of mast cell mediators and by facilitating allergen presentation to T cells. Mast cell activation also leads to the recruitment and activation of basophils and eosinophils, both of which express the Fc receptor on their surface and can therefore contribute to the IgE-mediated immune response.