The Analysis Of Risk Factors In Acute Graft Versus Host Disease Based On The Target Organs And The Investigation Of Biological Significance Of Tryptase

Objective To investigate the risk factors of target organs damages induced by acutegraft versus host disease（aGVHD）and the significance of tryptase in it.Methods (1)214patients received allogeneic hematopoietic stem celltransplantation（allo-HSCT） in Tongji Hospital from2003to2012were enrolled inthe study，and assessed on the overal grade of aGVHD and the degree of targetorgans GVHD damage.Then we studied the significance of the primary diseases、gender、age、pretreatment intensity、Donor type、the number of cell with CD34+positive expression、the use of ATG/ALG in the pretreatment scheme in theoccurrence of target organs damages and have assessed the response toimmunotherapy for target organs with different degrees of GVHD damages.(2)Wecollected46peripheral blood samples，and they were divided into2groups：gastrointestinal GVHD(GI-GVHD) group(n=21) and none GI-GVHD group（n=25）.The Enzyme linked immunosorbent assay(ELISA)was inducted toestimate the level of serum tryptase.(3)Mouse aGVHD models were conductedthrough injecting bone marrow cells and splenic cells，with the receipts receiving Tcell-deleted bone marrow cells as control group.The recipients in the GVHD groupwere observed the features of aGVHD.Tryptase expression in the tissues in the twogroups were detected by immunohistochemistry (IHC);mast cell protease6(MCP-6,the main subtype of tryptase in mice）mRNA level were detected through real time quantitative polymerase Chain reaction(real time-PCR) and the correlationbetween MCP-6and aGVHD was studied.Results （1）After univariate analyses and multivariate analyses，the graft type andthe pretreatment intensity were the risk factors of gastrointestinal GVHD(P<0.05)，while hepatic GVHD may be correlated with the primary diseases and pretreatmentintensity.Skin GVHD was correlated with the graft type.(2)Serum tryptaseconcentrations were elevated in patients with gastrointestinal GVHD，comparingwith the subjects without gastrointestinalGVHD（including with the skin/liverGVHD）. The statistical significance existed in them（P<0.05）.(3)Tryptase proteinexpression were elevated in intestine and liver in the aGVHD model mousecomparing with the control group，and the similar phenomenon was observed inMCP-6mRNA level (P<0.05).No statistical difference existed in the lung betweenthe two group in tryptase protein expression and MCP-6mRNA level.(P>0.05)Conclusion Pretreatment intensity was the risk factor of GI-GVHD, and theinspection of serum tryptase level may be helpful for the evaluation of GI-GVHDprogression and extension; tryptase and its subtype was relative special indistribution in GVHD target organs, and this suggest that it may be meaningful forinvestigation of GVHD target therapeutical drugs.