The Study Of Decreasing Chronic GVHD After Haploidentical HSCT By MSCs Derived From Murine Bone Marrow

Hematopoietic stem cells transplantation (HSCT) is more and more widely used in malignant hematopoietic disease, malignant non-hematopoietic disease, and some inherited disorders. Chronic graft-versus-host disease (cGVHD) is the common complication of allogeneic HSCT (allo-HSCT), which is a major cause of morbidity and mortality in long-term survivors. Therefore this study aims to establish a murine model of cGVHD after haploidentical HSCT, and to observe the effect of mesenchymal stem cells (MSCs) derived from bone marrow on cGVHD. This study includes the following two parts.Part â…  Establishment of a murine model of cGVHD after haploidentical HSCT1. Methods(BALB/c×C57BL/6)F₁^H-2d/b (CB6F₁) female mice which had been irradiated by different doses γ rays were injected of bone marrow cells and different number of spleen cells derived from BALB/c^H-2d male mice. Then the changes of its body weight, figure, fur, life span are observed. Engraftment was checked with karyotype analysis.Pathology of target organs was examined. And self-antibodies including anti-dsDNA antibody and anti-ssDNA antibody were detected by ELISA.2. Results(D Mice transplanted were partial chimeras. ?The groups transplanted survived by the terminal (+dlOO).The faces of the group which was irradiated by 8Gy y rays and injected of 8*106 bone marrow cells and 4.5xlO7 spleen cells denuded. The reduction of body weight of this group was much more than other groups (P<0.05).(3) Its self-antibodies were higher significantly than other groups (PO.05). ?The typical histologic findings of this group demonstrated coUagenous fibers in its dennis swelled, and fiber beam thickened. The nuclears of fibroblasts were round-like, around which lymphocyte involved. Its hair follicle, sebaceous glands, and sweat glands atrophied and diminished. The envelope of its liver thickened and roughed. The hepatic cord arranged mussily. The hepatic cells edema obviously. Lymphocytes were found infiltrated in portal area.3. ConclusionsWe have developed a murine model of cGVHD after haploidentical HSCT .The CB6F1 female mice which were irradiated by 8Gy y rays and injected of 8*106 bone marrow cells together with 4.5 *107 spleen cells had clinic feature of cGVHD on day 100 post-transplantation.Part II The effect of MSCs derived from bone marrow on cGVHD after haploidentical HSCT1. MethodsMSCS derived from BALB/c male mice bone marrow were isolated, cultured and expanded in vitro. The cGVHD in CB6F1 female mice induced as part I were injected of different number MSCs together with bone marrow cells and spleen cells. Then the items were observed including changes of its body weight, figure, fur, survival time. Engraftment was checked with karyotype analysis. Pathology of target organs was examined. Self-antibodies including anti-dsDNA antibody and anti-ssDNA antibody were detected by ELISA. IL-4 and IFN-y of plasma were detected by ELISA.2. ResultsThe mice transplanted were partial chimeras. On day 100 post-transplantation the group injected of high-dose of MSCs (8><106) had less reduction on body weight comparing with moderate-dose group and low-dose group and standard cGVHD group (PO.05). The self-antibodies of this group were decreased significantly (P<0.05).The pathological changes of target organs of this group were relieved. Comparing with standard cGVHD group, IL-4 concentration of high-dose group cut down (P<0.05) significantly, and IFN-y concentration rise up significantly.3. ConclusionsTo an extent* injecton of MSCs can decrease cGVHD after haploidentical HSCT. A dose-effect relationship is found between the quantity of MSCs and the decrease of cGVHD. CGVHD of the group injected high-dose MSCs decreased significantly comparing with other two groups. MSCs regulated function(s) of Thl/Th2 cells to decrease cGVHD after haploidentical HSCT.