[Environmental and immunological survey of sensitization with Japanese cedar (Cryotomeria japonica) pollen in children. Part 2. The clinical significance of Japanese cedar (Cryptomeria japonica) pollen specific IgE antibody and IgG4 antibody].

The clinical manifestations and Japanese cedar (sugi in Japanese) pollen specific antibodies were studied in 340 children who had not received specific hyposensitization. Specific IgE antibodies were measured by radioallergosorbent test (RAST) and IgG4 antibody by enzyme linked immunosorbent assay (ELISA). There were 52 children (15%) with RAST scores of over 2, and 44 children (13%) with ELISA of over 101 mu/ml. The specific IgG4 level was significantly higher in the RAST positive group than in the negative group. The incidence of pollinosis among children with RAST negative and IgG4 below 100 mu/ml was 13.3%, while combinations of RAST negative and higher ELISA, RAST positive and low ELISA, and RAST positive and higher ELISA were 50.0+-62.5%. There were 5 children with RAST scores of 4, and 6 children with ELISA of over 201 mu/ml. Symptoms of pollinosis manifested in all of them. Since the children with low IgE and high IgG4 antibodies had comparatively more symptoms, the IgG4 antibodies might be reaginic. It was concluded that measurement of sugi specific IgG4 antibodies as well as IgE antibodies could provide useful data on pollinosis in children.