Xian-Gui Peng

HLA-haploidentical blood and bone marrow transplantation with anti-thymocyte globulin: long-term comparison with HLA-identical sibling transplantation.

We present an update of our results regarding related HLA-haploidentical and HLA-identical sibling hematopoietic stem cell transplantation (HSCT) in patients with leukemia. We compared the outcomes of 107 patients with leukemia undergoing HLA-identical sibling (n=51) or related HLA-haploidentical (n=56) HSCT performed during the same time period. Patients received BU-CY/CY-TBI in HLA-identical sibling HSCT or TBI+Ara-C+CY+ATG/CCNU+Ara-C+Bu+CY+ATG in haploidentical HSCT as conditioning regimens, followed by unmanipulated marrow and/or peripheral blood (PB) transplantation. All patients achieved full engraftment. The cumulative incidence of grades II through IV acute graft-versus-host disease (aGvHD) in the matched and haploidentical cohorts was 13.7% and 26.8% (P<0.05), respectively. The risk of developing cGvHD was not different between HLA-matched and haploidentical patients (P>0.05). The two-year incidence of treatment-related mortality for matched and haploidentical patients was 7.8% and 12.5%, respectively, with P>0.05, and the incidence of relapse was 17% and 22%, respectively, with P>0.05. The two-year adjusted leukemia-free survival for matched versus haploidentical patients was 76% and 68%, respectively, with P>0.05, and the overall survival for matched versus haploidentical patients was 80% and 70%, respectively, with P>0.05. Multivariate analyses showed that only advanced disease stage and a diagnosis of acute leukemia were related to increased risk of relapse, treatment failure, and overall mortality. In summary, HSCT performed with related HLA-haploidentical donors is a feasible approach with acceptable outcomes.

Role of Antithymocyte Globulin and Granulocyte-Colony Stimulating Factor-Mobilized Bone Marrow in Allogeneic Transplantation for Patients with Hematologic Malignancies

The main obstacle for allogeneic transplantation is delayed hematologic reconstitution and serious graft-versus-host disease (GVHD). The results of 128 patients with hematologic malignancies undergoing HLA-identical (n=52) or HLA-haploidentical/mismatched (n=76) hematopoietic stem cell transplantation (HSCT) performed during the same time period were compared. Patients with HLA-identical HSCT received unmanipulated granulocyte-colony stimulating factor-mobilized peripheral blood stem cells (G-PBSCs). Forty-six patients with HLA-haploidentical related HSCT received antithymocyte globulin (ATG) in conditioning regimens followed by the transplantation of the combination of unmanipulated G-PBSCs and granulocyte-colony stimulating factor-mobilized bone marrow (G-BM) and 30 patients with HLA-mismatched unrelated HSCT received ATG in conditioning regimens followed by the transplantation of unmanipulated G-PBSCs. All patients got successful hematopoietic engraftment. The cumulative incidences of grades I to II acute GVHD (aGVHD) on day 100 in the identical, haploidentical related and mismatched unrelated cohorts were 21.2%, 43.5%, and 53.3%, respectively. The cumulative incidences of chronic GVHD (cGVHD) in the identical, mismatched unrelated, and haploidentical related cohorts were 34.6%, 33.3%, and 10.9%, respectively. The 2-year relapse and treatment-related mortality (TRM) rates were 19.2%, 23.9%, 23.3%, and 9.6%, 8.7%, 10% for patients who underwent identical, HLA-haploidentical related, and mismatched unrelated transplantation, respectively. The 2-year probabilities of leukemia-free survival and overall survival were 72.2%, 70.6%, 68.1%, and 76.5%, 77.8%, 70.0% after identical, haploidentical related and mismatched unrelated transplantations, respectively. Multivariate analyses showed that only advanced disease stage and a diagnosis of disease had increased risk of relapse, treatment failure, and overall mortality. In conclusion, it is a feasible approach with acceptable outcomes for patients undergoing HLA-haploidentical related HSCT by the combination of G-PBSCs and G-BM with conditioning regimens including ATG.

Human umbilical cord blood-derived stromal cells, a new resource in the suppression of acute graft-versus-host disease in haploidentical stem cell transplantation in sublethally irradiated mice.

Human umbilical cord blood-derived stromal cells (hUCBDSCs), a novel population isolated from CD34+ cells by our laboratory, exerted an immunosuppressive effect on xenogenic T cells. This study aimed to investigate whether hUCBDSCs play a critical role in the suppression of acute graft-versus-host disease (aGVHD). The hUCBDSCs were co-cultured with splenocytes (SPCs) of donor C57BL/6 mice. The aGVHD in the recipient (B6×BALB/c) F1 mice was induced by the infusion of bone marrow cells and SPCs from donor mice following sublethal irradiation. The shift in vivo for hUCBDSCs was detected. The proliferation and cell cycle of SPCs were tested by cell counting kit-8 and flow cytometry, respectively. The expression of CD49b natural killer (NK) cells and CD3 T cells was detected by flow cytometry in co-culture and post-transplantation. IL-4, and IFN-γ were detected by ELISA in the serum of co-culture and post-transplantation. The survival time, body weight, clinical score, and histopathological score were recorded for mice post-transplantation. The hUCBDSCs promoted the proliferation of SPCs and significantly increased the ratio of the S and G2/M phase (p < 0.05). The hUCBDSCs significantly increased the expression of CD49b NK cells and IL-4 protein and decreased the expression of CD3 T cells and IFN-γ protein both in vitro and in vivo. The survival time of mice with co-transplantation of hUCBDSCs was significantly prolonged, and decreased clinical and histopathological scores were also observed. The hUCBDSCs were continually detected in the target organs of GVHD. These results suggest that hUCBDSCs possess the capability of suppressing aGVHD, possibly via their influence on CD3 T cells, NK cells, and cytokines.

Stem cell collection in unmanipulated HLA-haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised blood and bone marrow for patients with haematologic malignancies: the impact of donor characteristics and procedural settings.

Unmanipulated haploidentical/mismatched related transplantation with combined granulocyte‐colony stimulating factor‐mobilised peripheral blood stem cells (G‐PBSCs) and granulocyte‐colony stimulating factor‐mobilised bone marrow (G‐BM) has been developed as an alternative transplantation strategy for patients with haematologic malignancies. However, little information is available about the factors predicting the outcome of peripheral blood stem cell (PBSC) collection and bone marrow (BM) harvest in this transplantation. The effects of donor characteristics and procedure factors on CD34+ cell yield were investigated. A total of 104 related healthy donors received granulocyte‐colony stimulating factor (G‐CSF) followed by PBSC collection and BM harvest. Male donors had significantly higher yields compared with female donors. In multiple regression analysis for peripheral blood collection, age and flow rate were negatively correlated with cell yield, whereas body mass index, pre‐aphaeresis white blood cell (WBC) and circulating immature cell (CIC) counts were positively correlated with cell yields. For BM harvest, age was negatively correlated with cell yields, whereas pre‐BM collection CIC counts were positively correlated with cell yield. All donors achieved the final product of ≥6 ×106 kg−1 recipient body weight. This transplantation strategy has been shown to be a feasible approach with acceptable outcomes in stem cell collection for patients who received HLA‐haploidentical/mismatched transplantation with combined G‐PBSCs and G‐BM. In donors with multiple high‐risk characteristics for poor aphaeresis CD34+ cell yield, BM was an alternative source.

Mobilization of peripheral blood stem cells for autologous transplantation patients with hematological malignancies: Influence of disease, mobilization method, age and sex

Autologous peripheral blood stem cells transplantation (Auto-PBSCT) is a therapeutic option which can be used in various hematological neoplastic disorders; and it can prolong disease-free survival and total survival. Many factors could influence the mobilization of peripheral blood stem cells for patients of Auto-PBSCT. In this study, we investigated the variables influencing the mobilization of peripheral blood stem cells in 240 patients with hematological malignancies who had undergone Auto-PBSCT between 2001 and March 2007 in our center, retrospectively. Patients with acute myelogenous leukemia had the most collected mononuclear cells (MNCs) and patients with acute lymphoblastic leukemia had the most collected CD34(+) cells than did other patients. However, patients with multiple myeloma had the least collected MNCs and CD34(+) cells. Patients mobilized with chemotherapy with granulocyte colony stimulating factor (G-CSF) plus recombinant human interleukin-11(rhIL-11) had the most collected MNCs and CD34(+) cells. The difference is statistical signification between chemotherapy with G-CSF and chemotherapy with G-CSF plus rhIL-11 for collected MNCs (P<0.05). Adults had the most collected MNCs and CD34(+) cells and the difference is statistical signification between children/adolescent and older, children/adolescent and adult for CD34(+) cells (P<0.05). Male patients had the more collected MNCs and CD34(+) cells and the difference is statistical signification for CD34(+) cells (P<0.05). The adverse events were not serious during mobilization. In conclusion, many factors could influence the mobilization of peripheral blood stem cells, and our findings emphasize the need to optimize harvesting technique to enhance safety and minimize morbidity and costs of this valuable procedure.

Human umbilical cord blood-derived stromal cells prevent graft-versus-host disease in mice following haplo-identical stem cell transplantation

BACKGROUND AIMS Human umbilical cord blood-derived stromal cells (hUCBDSC) comprise a novel population of CD34(+) cells that has been isolated in our laboratory. They have been shown previously not only to be non-immunogenic but also to exert immunosuppressive effects on xenogenic T cells in vitro. This study investigated the role of hUCBDSC in immunomodulation in an acute graft-versus-host disease (GvHD) mouse model after haplo-identical stem cell transplantation. METHODS Acute GvHD was induced in recipient (B6 × BALB/c)F(1) mice by irradiation (750 cGy) followed by infusion of bone marrow cells and splenocytes from donor C57BL/6 mice. hUCBDSC were co-transplanted in the experimental group. The survival time, body weight and clinical and histopathologic scores were recorded after transplantation. The expression of surface markers [major histocompatibility complex (MHC) I, MHC II, CD80 and CD86] on CD11c(+) dendritic cells (DC), and the percentage of CD4(+) regulatory T cells (Treg), in the spleens of recipient mice were examined by flow cytometry. RESULTS The survival time was significantly prolonged, and the clinical and histopathologic scores were reduced in mice co-transplanted with hUCBDSC. The expression levels of the surface markers on DC were significantly lower in mice transplanted with hUCBDSC compared with those without. The proportion of CD4(+) Treg in the spleen was also increased in mice transplanted with hUCBDSC. CONCLUSIONS These results from a GvHD mouse model are in agreement with previous in vitro findings, suggesting that hUCBDSC possess immunosuppressive properties and may act via influencing DC and CD4(+) Treg.

Human bone marrow mesenchymal stem cells expressing SDF-1 promote hematopoietic stem cell function of human mobilised peripheral blood CD34+ cells in vivo and in vitro

Purpose: There is mounting evidence demonstrating that stromal cell derived factor-1 (SDF-1) plays an important role in homing of hematopoietic progenitor cells to bone marrow. This study was aimed to assess whether bone marrow mesenchymal stem cells overexpressing exogenous SDF-1 could synergistically promote the homing of CD34+ (Cluster of Differentiation [CD]) cells to bone marrow of lethally irradiated severe combined immunodeficiency (SCID) mice. Methods: Human SDF-1 complementary Deoxyribonucleic acid (cDNA) was transfected into bone marrow-derived mesenchymal stem cells with recombinant lentiviral vector. The expression of SDF-1 was detected by real-time Polymerase Chain Reaction (PCR) and Enzyme-Linked Immunosorbent Assay (ELISA), and the ex vivo chemotaxis function on CD34+ cells was measured by coculture system and Transwell system. SDF-1 gene-modified mesenchymal stem cell (MSC) and CD34+ cells were infused into lethally irradiated SCID mice and the hematopoietic reconstitution in the recipient mice was examined. Results: Messenger ribonucleic acid (mRNA) and protein of SDF-1 in infected MSC were significantly higher than that of the non-infected control MSC (p < 0.05). The infected MSC have significant chemotaxis effect on CD34+ cells in vitro and promote hematopoietic reconstitution after CD34+ cell transplantation in vivo. Conclusion: MSC with high-level expression of SDF-1 can synergistically promote hematopoietic reconstitution after CD34+ cell transplantation in lethally irradiated SCID mice.

Human umbilical cord blood-derived stromal cells: Multifaceted regulators of megakaryocytopoiesis

It has been demonstrated that stromal cell precursors exist in human umbilical cord blood. After being cultured in vitro, these cells are called human umbilical cord blood-derived stromal cells (hUCBDSCs). However, the role of hUCBDSCs in hematopoiesis is still unclear. We have previously shown that hUCBDSCs are superior to human bone marrow stromal cells (hBMSCs) at enhancing the expansion of megakaryocyte colony forming units (CFU-Meg). Based on this observation, we postulated that hUCBDSCs might promote megakaryocytopoiesis. To test this hypothesis, we developed a megakaryocyte/hUCBDSC co-culture model and a hematopoietic microenvironment injury model in nude mice. We explored the ability and mechanisms by which hUCBDSCs promoted the proliferation of megakaryocytes in vitro, and we also explored their capacity to restore the hematopoietic microenvironment in vivo. As expected, hUCBDSCs were more effective than hBMSCs at enhancing the proliferation of megakaryocyte lines from HEL cells and restoring megakaryocytopoiesis in a hematopoietic microenvironment injury model in nude mice. Thrombopoietin (TPO) and stromal cell derived factor-1 (SDF-1) are two of the key factors underlying this capacity. We also found that gap junction intercellular communication (GJIC) between HEL cells and hUCBDSCs might be partially absent. Our data provide the first evidence that hUCBDSCs play a regulatory role during megakaryocytopoiesis, which might be important for designing treatments for patients with megakaryocytic injury.

Human Umbilical Cord Blood-Derived Stromal Cells Are Superior to Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells in Inducing Myeloid Lineage Differentiation In Vitro

Stromal cells and mesenchymal stem cells (MSCs), 2 important cell populations within the hematopoietic microenvironment, may play an important role in the development of hematopoietic stem/progenitor cells. We have successfully cultured human umbilical cord blood-derived stromal cells (hUCBDSCs). It has been demonstrated that MSCs also exist in hUCB. However, we have not found any reports on the distinct characteristics of hUCBDSCs and human umbilical cord blood-derived mesenchymal stem cells (hUCBDMSCs). In this study, hUCBDSCs and hUCBDMSCs were isolated from the cord blood of full-term infants using the same density gradient centrifugation and cultured in the appropriate medium. Some biological characteristics and hematopoietic supportive functions were compared in vitro. hUCBDSCs were distinct from hUCBDMSCs in morphology, proliferation, cell cycle, passage, immunophenotype, and the capacity for classical tri-lineage differentiation. Finally, quantitative real-time polymerase chain reaction analysis revealed that granulocyte colony-stimulating factor (G-CSF) gene expression was higher in hUCBDSCs than that in hUCBDMSCs. Enzyme-linked immunosorbent assay revealed that the secretion of G-CSF, thrombopoietin (TPO), and granulocyte macrophage colony-stimulating factor (GM-CSF) by hUCBDSCs was higher than that by hUCBDMSCs. After coculture, the granulocyte/macrophage colony-forming units (CFU-GM) of hematopoietic cells from the hUCBDSC feeder layer was more than that from the hUCBDMSC feeder layer. Flow cytometry was used to detect CD34(+) hematopoietic stem/progenitor cell committed differentiation during 14 days of coculture; the results demonstrated that CD14 and CD33 expression in hUCBDSCs was significantly higher than their expression in hUCBDMSCs. This observation was also true for the granulocyte lineage marker, CD15. This marker was expressed beginning at day 7 in hUCBDSCs. It was expressed earlier and at a higher level in hUCBDSCs compared with hUCBDMSCs. In conclusion, hUCBDSCs are different from hUCBDMSCs. hUCBDSCs are superior to hUCBDMSCs in supporting hematopoiesis stem/progenitor cells differentiation into myeloid lineage cells at an early stage in vitro.

Cost and outcome in stem cell collections in HLA-haplo identical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilized blood and bone marrow for patients with hematologic malignancies

Unmanipulated HLA-haplo identical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilized peripheral blood stem cells (G-PBSCs) and granulocyte-colony stimulating factor-mobilized bone marrow (G-BM) has been developed as an alternative transplantation strategy for patients without an HLA-matched related or unrelated donor. In this transplantation setting, the cost and outcome of stem cell collections have not been defined completely. The aim of this study was to compare the cost and outcome of stem cell collection in HLA-haplo identical/mismatched related transplantation with combined G-PBSCs and G-BM to the HLA-identical/matched transplantation with G-PBSCs alone for patients with hematologic malignancies. Hundred and fifty-two healthy donors received twice-daily granulocyte-colony stimulating factor (G-CSF) subcutaneously for 5 days. The PBSCs were collected on day 4 and 5 of G-CSF treatment for HLA-identical/matched transplantation from unrelated/related donors. The PBSC collections and BM harvests was performed on day 4 and 5 of G-CSF treatment for HLA-haplo identical/mismatched related transplantation from related donors, respectively. There was no difference in the major characteristics between groups. More stem cells were harvested in HLA-haplo identical/mismatched related donors than that of HLA-identical/matched donors and a lower cost was seen in the former. The HLA-haplo identical/mismatched related transplantation with combined G-PBSCs and G-BM was a feasible approach with high cell harvest and low cost of stem cell collection for patients with hematologic malignancies.