Select procyanidins prime the γδ T cell by modulating transcriptome degradation (134.88)

Abstract

Abstract Tannins from many plant-derived traditional medicines demonstrate immune regulatory activity. Recently, we reported that condensed tannins (procyanidins) isolated from a select number of traditional medicines act as γδ T cell agonists. γδ T cells play an important role in mucosal immunity by regulating the mucosal immune response and maintaining epithelial health. Procyanidins induce a priming state on the γδ T cell, thus improving its ability to quickly respond to secondary stimuli. This priming state is characterized, in part, by an increased half-life of select transcripts in the γδ T cell relevant to innate immunity. This increase in transcript half-life could enable the cell to more quickly produce appropriate immune responses to secondary stimuli. Previously we reported that oligomeric procyanidin fractions, but not monomeric procyanidins, act as γδ T cell agonists. We have further defined the activity of different sizes of procyanidins. The tetrameric and pentameric procyanidins from apple peel have greater specificity for γδ T cells, whereas larger oligomers demonstrate less specificity. Our results suggest procyanidins with specific oligomeric structures prime γδ T cells by stabilizing transcripts with critical functions in innate immunity. Funded by: NIH/ NIAID Contract HHSN266200400009/N01-AI40009 and NCCAM P01 AT004986-01