Expression of Dermatophagoides pteronyssinus allergen, Der p II, in Escherichia coli and the binding studies with human IgE.

Lambda gt11 clones expressing the major house dust mite allergen, Der p II, have been reported to react with IgE in the serum of a high proportion of allergic patients. The clones described, however, only produced small quantities of protein which was not fused to the beta-galactosidase of the vector. A construct of the Der p II is described which produces a fusion of Der p II, minus its leader sequence, with the glutathione-S transferase in the pGEX vector. This could be readily isolated and was shown to react with IgE in 22 of 24 patient sera showing reactivity to native Der p II, the sera not reacting having low reactivity to native protein. Absorption analysis showed that the recombinant material removed most of the IgE reactivity of patients to native Der p II. The construct described, therefore, should be valuable for quantitative studies of a pure mite allergen.