IgE, IgG, and IgG4 antibody titers to fractionated house dust mite antigens in nasal allergy patients.

Using 6 fractions differing in molecular weight of Dermatophagoides pteronyssinus (Dp)-antigen, we measured by enzyme-linked immunosorbent assay (ELISA) the titers of specific IgE, IgG and IgG4 antibodies against Dp antigen in sera of allergic subjects who were sensitive to house dust mite. We intended to evaluate which Dp fraction acts as the major antigenicity for allergic subjects. Results were as follows: 1) In comparison with normal controls, the titer of IgE antibody specific to crude Dp antigen was evaluated, but no significant difference was found among the titers of IgE antibody against each Dp fraction. 2) The titer of IgG antibody against the fraction with a high molecular weight (190 KD, 95 KD) was significantly higher than the titer of the 15 KD fraction in the nasal allergy patients. 3) The 15 KD fraction induced significant elevation of the titer of IgG4 antibody. It suggests that the low molecular weight fraction may act as the major allergenicity of Dp-antigen for inducing both IgE and competitive IgG4 antibodies, although other fractions induce significant IgE responses in patients with nasal allergy.