[Investigation of the variation of Cry j 2 concentration in pollen among sugi (Cryptomeria japonica d. Don) trees using a newly established extraction method].

BACKGROUND: Selection of low-allergen trees is under consideration for the reduction of Sugi (Cryptomeria japonica) pollinosis. The extraction method of Cry j 2 was established and then the variation of Cry j 2 concentrations in pollen among Sugi trees was investigated. METHODS: The extraction efficiency of Cry j 2 was compared among buffers with different pH, ionic species and NaCl concentration. The Cry j 2 concentration in the pollen of 140 trees was measured using the most efficient buffer. RESULTS: NaHCO3 (0.125 M) + 0.5 M NaCl buffer showed the highest Cry j 2 extraction efficiency. The mean and standard deviation of Cry j 2 concentration among 140 trees was 404 +/- 189 microg/g pollen, which was equivalent to that of Cry j 1 (435 +/- 169 microg). CONCLUSION: We revealed that the variation of Cry j 2 concentrations was as large as that of Cry j 1 in the pollen among trees using the newly developed extraction method.

Influences of genetic and environmental factors on the concentration of the allergen Cry j 1 in sugi (Cryptomeria japonica) pollen.

Pollen from sugi (Japanese cedar, Cryptomeria japonica D. Don), a forest tree species that is widely grown in Japan, causes serious allergic disease. The major allergens from sugi pollen, Cry j 1 and Cry j 2, have been isolated and characterized. It has been reported that Cry j 1 concentration in pollen varies considerably among trees. If Cry j 1 concentration is genetically controlled, the planting of trees with low Cry j 1 concentrations would reduce pollinosis. We investigated genetic and environmental effects on Cry j 1 concentration in eight clones growing at four sites. Concentrations of Cry j 1 in pollen were measured with a monoclonal antibody-based Enzyme Linked Immunosorbent Assay (ELISA). The Cry j 1 concentrations differed significantly among clones and sites, but the site x clone interaction was not significant, suggesting that the Cry j 1 concentration is controlled primarily by genetic factors. We examined correlations between Cry j 1 concentration and temperature and precipitation from July through February. Temperature was not significantly related to Cry j 1 concentration, whereas cumulative precipitation during the 8 months and mean daily precipitation in September showed significant negative correlations with Cry j 1 concentration.