Abstract: Objective To investigate whether there is common antigen between Tyrophagus putrescentiae (TP) and Dermatophagoides farine (DF) or not.Methods The correlation of ELISA optic densities between TP and DF-specific IgE in atopic sera was analyzed,and TP and DF extracts were analyzed with SDS-PAGE.IgE immunoblotting and IgE inhibition immunoblotting to TP and DF extracts with atopic sera were performed also.Results  The ELISA optic densities of TP and DF-specific IgE in 42 atopic sera were correlated with each other (r=0.641 5，P＜0.01).By SDS-PAGE,the protein components of the TP and DF extracts were numerous protein bands between 10 kD and 110 kD.In addition,the presence of a cross-reactive IgE binding component in the TP and DF major allergens was investigated by IgE inhibition immunoblotting experiments.Conclusion There is common antigen between Tyrophagus putrescentiae and Dermatophagoides farine.

Key words: Tyrophagus putrescentiae, Dermatophagoides farine, common antigen, Acaridida