The Effect of γ-secretase Inhibitor Combined with BMSC on the aGVHD in Mice Model / 中国实验血液学杂志

OBJECTIVE@#To establish the aGVHD mouse model，and investigate the regulatory effect and its mechanism of low-dose GSI combined with BMSC on aGVHD mice.@*METHODS@#C57BL/6 (H-2b) and BALB/c (H-2d) were selected as donor and recipient of allogeneic transplantation to establish the aGVHD mouse model. BALB/c mice were randomly divided into 6 groups, which were the bone marrow cell infusion after irradiation (BM) group; the bone marrow cells + spleen cells after irradiation (BM+SC) group; the bone marrow cells + spleen cells + DMSO (BM+SC+DMSO) (transplant control) group; bone marrow cells + splenocytes +GSI after irradiation (BM+SC+GSI) group; bone marrow cells + spleen cells + bone marrow mesenchymal stromal infusion after irradiation cell (BM+SC+BMSC) group; bone marrow cells + spleen cells + bone marrow mesenchymal stromal cells +GSI infused after irradiation (BM+SC+BMSC+GSI) group. The mice in the two groups containing GSI were intraperitoneally injected with GSI at 5 μmol/kg on day 1, 2, and 3 after transplantation with DMSO as a control. The general conditions, survival time and hematopoietic recovery of mice were observed, cytokines were detected by ELISA, and histopathological changes were detected by immunohistochemistry. The effects of low-dose GSI combined with BMSC on hematopoietic reconstruction and aGVHD development after allo-BMT were investigated.@*RESULTS@#The survival rate of the mice in BM+SC+BMSC+GSI combination group was 80% during the observation period, which was significantly higher than that in the other groups; the incidence of aGVHD was reduced in the BMSC GSI or their combination groups after 21 days of transplantation. GSI could partly promote the recovery of leukocytes, and show no significant delayed effect on the recovery platelets. Moreover, the level of Th1 cytokines (IFN-γ) in BM+SC+BMSC+GSI combined group was lower than that in BM+SC+GSI group (P<0.01), the level of Th2 cytokines (IL-4) in the combination group was higher than that in BM+SC+GSI group (P<0.01), also the level of IL-17 was significantly lower than that in the corresponding control group (P<0.001).@*CONCLUSION@#Low dose GSI combined with BMSC can promote hematopoietic reconstruction and regulate cytokines secretion including IFN-γ, IL-4 and IL-17. GSI combined with BMSC achieve the goal of synergistically inhibiting the occurrence and progression of aGVHD.

Effects of Arsenic Disulfide Combined with Itraconazole on Proli- feration and Apoptosis and Hedgehog Pathway of Diffuse Large B-Cell Lymphoma Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of arsenic disulfide (AS@*METHODS@#The human DLBCL cell OCI-LY3 was treated with different concentrations of AS@*RESULTS@#The DLBCL cell viability was decreased significantly at 24, 48 or 72 h as cultured with itraconazole. Along with the increasing of itraconazole concentration, the DLBCL cell viability was significantly reduced as compared with that in control group, and the results showed statistically significant(r=-0.690，r=-0.639, r=-0.833, r=-0.808, r=-0.578). The inhibitory and apoptosis rates of the cells were significantly increased as compared with those of the single drug-treated group after treated by the combination of itraconazole and AS@*CONCLUSION@#Itraconazole can inhibit proliferation of DLBCL cells in a concentration-and time-dependent manner. In addition, the combination of AS

Research Progress on Notch Signal Pathway in Acute Graft-Versus-Host Disease -Review / 中国实验血液学杂志

The Notch signaling pathway is a highly conserved cell signaling system that plays an essential role in many biological processes. Notch signaling regulates multiple aspects of hematopoiesis, especially during T cell develop-ment. Recent data suggest that Notch also regulates mature T cell differentiation and function. The latest data show that Notch also plays an essential role in alloreactive T cells mediating acute graft-versus-host disease (aGVHD), the most severe complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Notch inhibition in donor-derived T cells or blockade of individual Notch ligands and receptors after transplantation can reduce GVHD severity and mortality in mouse models of allo-HSCT, without causing global immunosuppression. These findings indicate Notch in T cells as an attractive therapeutic target to control aGVHD. In this article, the pathophysiology of aGVHD, the Notch signal pathway and aGVHD are reviewed.

Inhibitory effects of gamma secretase inhibitor on human multiple myeloma xenograft mouse model / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the tumor growth inhibition of gamma secretase inhibitor MRK003 on human multiple myeloma xenograft mice by inhibition of AKT and Notch1 expression.</p><p><b>METHODS</b>NOD/SCID mice were injected with human multiple myeloma cell lines RPMI8226 to establish a xenograft mouse model. Mice were randomized into two groups：the experimental group were injected with MRK003 at a dose of 5 mg× kg⁻¹×d⁻¹ for 14 days; the inhibitor was replaced by an equal saline in the control group. Mice were sacrificed by cervical dislocation on the next day after the last injection and tumor tissue was removed to detect the expression of Notch1 and AKT by immunohistochemistry.</p><p><b>RESULTS</b>After subcutaneous injection with RPMI8226, mice had tumor formation in 5-7 days and the largest tumor block in 10-12 days. Before RPMI8226 injection, the mean sizes of tumor block in the experimental and the control groups were 509.2 mm³, 511.2 mm³(P>0.05). 9 days after injection, the mean sizes of tumor tissue in the experimental and the control groups were 636.6 mm³, 691.2 mm³(P<0.01). On the next day after the last injection, the tumor sizes of the experimental and the control groups were 683.5 mm³ and 1798.7 mm³(P<0.01). The size of tumor block in the experimental group was significantly smaller than that of the control group(P<0.01). Immunohistochemistry staining showed that the positive expression rates of Notch1(11.1%, P<0.01) and AKT(13.3%, P<0.01) in experimental group were significantly decreased compared with the control group(Notch1: 95.6%; AKT: 93.3%). Western blot results showed that Notch1 and AKT protein in experimental group were significantly lower than those in the control group.</p><p><b>CONCLUSION</b>MRK003 could inhibit the tumor growth of human multiple myeloma xenograft mice by downregulated expression of Notch1 signaling pathway.</p>