Toll-like receptors (TLRs), which are found in innate immune cells, are essential mediators of rapid inflammatory responses and appropriate T-cell activation in response to infection and tissue damage. Accumulating ...Toll-like receptors (TLRs), which are found in innate immune cells, are essential mediators of rapid inflammatory responses and appropriate T-cell activation in response to infection and tissue damage. Accumulating evidence suggests that TLR signaling is involved in normal hematopoiesis and specific hematologic pathologies. Particular TLRs and their downstream signaling mediators are expressed not only in terminally differentiated innate immune cells but also in early hematopoietic progenitors. Sterile activation of TLR signaling is required to generate early embryonic hematopoietic progenitor cells. In adult animals, TLR signaling directly or indirectly promotes differentiation of myeloid cells at the expense of that of lymphoid cells and the self renewal of hematopoietic stem cells during infection and tissue damage. Activating mutations of the MyD88 gene, which codes for a key adaptor involved in TLR signaling, are commonly detected in B-cell lymphomas and other B-cell hematopathologies. Dysregulated TLR signaling contributes to the pathogenesis of many hematopoietic disorders, including bone marrow failure, myelodysplastic syndrome, and acute myeloid leukemia. Complete elucidation of the molecular mechanisms by which TLR signaling mediates the regulation of both normal and pathogenic hematopoiesis will prove valuable to the development of targeted therapies and strategies for improved treatment of hematopoietic disorders.展开更多
Adult derived mononuclear bone marrow cells are a good alternative as cell therapy. These cells are capable of significantly improve survival rate of Wistar rats with acetaminophen (APAP) induced acute liver failure i...Adult derived mononuclear bone marrow cells are a good alternative as cell therapy. These cells are capable of significantly improve survival rate of Wistar rats with acetaminophen (APAP) induced acute liver failure in ten days. However, long term of cell therapy is not deeply studied in the literature. Here, we report an extramedullary hematopoiesis process derived from transplanted mononuclear bone marrow cells in the liver of rats 10 days after APAP injection. This result indicates that liver maintains an adequate microenvironment for the occurrence of extramedullary hematopoiesis process. The consequence of this finding deserves more studies.展开更多
The effect of Ligustrazine on the hematopoiesis after bone marrow transplantation (BMT) in allogenic BMT mice was investigated. After the typical mice model of allogenic BMT had been established, the mice were random...The effect of Ligustrazine on the hematopoiesis after bone marrow transplantation (BMT) in allogenic BMT mice was investigated. After the typical mice model of allogenic BMT had been established, the mice were randomly divided into three groups: BMT group, Ligustrazine group and normal group. The BMT group was given normal saline (0.2 ml, twice a day) through gastric tube, while the Ligustrazine group was given Ligustrazine through gastric tube (0.2 ml, twice a day). At the 1st, 7th and 14th day after BMT, we observed the peripheral blood cells and bone marrow nuclear cells (BMNC), as well as the expression level of Heparan Sulfate (HS) and stromal cell derived factor 1 (SDF 1) on bone marrow sections by using immunohistochemistry (SABC AP), the expression of CXCR4 on the BMNC. The results showed that on the 7th and 14th day, the peripheral blood white cells, platelets, BMNC and the expression levels of CXCR4, HS and SDF 1 were significantly higher in Ligustrazine group than in the BMT group ( P <0.05). It was concluded that Ligustrazine could promote hematopoiesis at the early stage of hematopoietic reconstitution after BMT.展开更多
文摘Toll-like receptors (TLRs), which are found in innate immune cells, are essential mediators of rapid inflammatory responses and appropriate T-cell activation in response to infection and tissue damage. Accumulating evidence suggests that TLR signaling is involved in normal hematopoiesis and specific hematologic pathologies. Particular TLRs and their downstream signaling mediators are expressed not only in terminally differentiated innate immune cells but also in early hematopoietic progenitors. Sterile activation of TLR signaling is required to generate early embryonic hematopoietic progenitor cells. In adult animals, TLR signaling directly or indirectly promotes differentiation of myeloid cells at the expense of that of lymphoid cells and the self renewal of hematopoietic stem cells during infection and tissue damage. Activating mutations of the MyD88 gene, which codes for a key adaptor involved in TLR signaling, are commonly detected in B-cell lymphomas and other B-cell hematopathologies. Dysregulated TLR signaling contributes to the pathogenesis of many hematopoietic disorders, including bone marrow failure, myelodysplastic syndrome, and acute myeloid leukemia. Complete elucidation of the molecular mechanisms by which TLR signaling mediates the regulation of both normal and pathogenic hematopoiesis will prove valuable to the development of targeted therapies and strategies for improved treatment of hematopoietic disorders.
基金This work was supported by National Natural Science Foundation of China (30300119 and30030070) Research Fundfor the Doctoral Program of Higher Education from the Ministry of Education of China (20030533002)
文摘Adult derived mononuclear bone marrow cells are a good alternative as cell therapy. These cells are capable of significantly improve survival rate of Wistar rats with acetaminophen (APAP) induced acute liver failure in ten days. However, long term of cell therapy is not deeply studied in the literature. Here, we report an extramedullary hematopoiesis process derived from transplanted mononuclear bone marrow cells in the liver of rats 10 days after APAP injection. This result indicates that liver maintains an adequate microenvironment for the occurrence of extramedullary hematopoiesis process. The consequence of this finding deserves more studies.
基金This project was supported by the National Natural ScienceFoundation(39870 92 6 ) .
文摘The effect of Ligustrazine on the hematopoiesis after bone marrow transplantation (BMT) in allogenic BMT mice was investigated. After the typical mice model of allogenic BMT had been established, the mice were randomly divided into three groups: BMT group, Ligustrazine group and normal group. The BMT group was given normal saline (0.2 ml, twice a day) through gastric tube, while the Ligustrazine group was given Ligustrazine through gastric tube (0.2 ml, twice a day). At the 1st, 7th and 14th day after BMT, we observed the peripheral blood cells and bone marrow nuclear cells (BMNC), as well as the expression level of Heparan Sulfate (HS) and stromal cell derived factor 1 (SDF 1) on bone marrow sections by using immunohistochemistry (SABC AP), the expression of CXCR4 on the BMNC. The results showed that on the 7th and 14th day, the peripheral blood white cells, platelets, BMNC and the expression levels of CXCR4, HS and SDF 1 were significantly higher in Ligustrazine group than in the BMT group ( P <0.05). It was concluded that Ligustrazine could promote hematopoiesis at the early stage of hematopoietic reconstitution after BMT.