REGULATION OF CYTOKINE PRODUCTION BY SUGI ALLERGEN-PULLULAN CONJUGATE

Sugi basic protein (SBP), a major allergen if Japanese cedar (Cryptome ria japonica) pollen, conjugated to pullulan (alpha-1,4', alpha-1,6'-g lucan) reportedly suppresses IgE anti-SBP antibody production and enha nces IgG anti-SBP antibody production in mice. We analyzed cytokine pr oduction by SBP-specific T cells after stimulation with an ABP-pullula n conjugate (SBP-P), native SBP, or a mixture if SBP and pullulan. Whe n SBP-specific T cell lines were stimulated with the SBP-P conjugate i n the presence of antigen-presenting cells (APC), the production of IF N-gamma, IL-4, IL-5, and IL-10 decreased compared with the cytokine le vels produced by SBP-stimulated T cells. However, when these T cells w ere repeatedly stimulated with the SBP-P conjugate, the production of IFN-gamma increased progressively, while that of IL-4, IL-5, and IL-10 remained decreased compared with the T cells that were repeatedly sti mulated with native SBP. Stimulation of the T cells with the mixture o f SBP and pullulan showed little difference in the cytokine production profile from that observed after stimulation with native SBP alone. I nterestingly, when the T cell lines stimulated repeatedly with SBP-P w ere subsequently stimulated with native SBP, a further increase in IFN -gamma production was observed, while IL-10 production decreased. Inhi bition of IL-4 production was also observed when SBP-specific TH2 clon es were stimulated with SBP-P. These results indicate that stimulation of T cells with SBP-P up-regulates Th1 cytokine production, while dow n-regulating that of Th2. It is, therefore, conceivable that immunothe rapeutic treatment with the SBP-P conjugate rather than with conventio nal SBP solutions is preferable for improving Japanese cedar pollen al lergy.