The Intestinal Stem Cell Compartment is the Initial Target of T Cell Invasion in GI Gvhd

Abstract

the non-GI group had the highest diversity after day-20, followed by UGI group. The LGI group had the lowest microbial diversity (Figure 1A). When samples were grouped into preonset (day-19 to day 0) and post-onset (day 1 to day 20) bins, the microbial diversity in LGI cases was already significantly lower than UGI and non-GI groups prior to aGVHD onset (median S 2.05 vs 2.65 and 3.45, respectively, P < .05, Mann Whitney test). This trend became more pronounced after aGVHD onset (median S 3.14 vs 5.73 and 7.20, respectively, P < .005, Figure 1B). Conclusions: Patients with non-GI aGVHD or UGI show higher microbial diversity when compared to the LGI group. Of particular interest is the fact this trend starts before the onset of aGVHD, indicating eventual possibility of early intervention. These findings are consistent with a model in which a diverse gut microbiota exerts a local protective effect in lower GI aGVHD and have potential practical implications in future prophylactic and therapeutic interventions in aGVHD.