Infusion of haploidentical hematopoietic stem cells combined with mesenchymal stem cells for treatment of severe aplastic anemia in adult patients yields curative effects.

BACKGROUND AIMS: Despite the great advances in immunosuppressive therapy for severe aplastic anemia (SAA), most patients are not completely cured. Haploidentical hematopoietic stem cell transplantation (haplo-HSCT) has been recommended as an alternative treatment in adult SAA patients. However, haplo-HSCT presents a higher incidence of graft failure and graft-versus-host disease (GVHD). The authors designed a combination of haplo-HSCT and umbilical cord-derived mesenchymal stem cells (UC-MSCs) for treatment of SAA in adult patients and evaluated its effects. METHODS: Adult patients (≥18 years) with SAA (N = 25) were given HLA-haploidentical hematopoietic stem cells (HSCs) combined with UC-MSCs after a conditioning regimen consisting of busulfan, cyclophosphamide, fludarabine and anti-thymocyte globulin and intensive GVHD prophylaxis, including cyclosporine, basiliximab, mycophenolate mofetil and short-term methotrexate. Additionally, the effects of the protocol in adult SSA patients were compared with those observed in juvenile SAA patients (N = 75). RESULTS: All patients achieved myeloid engraftment after haplo-HSCT at a median of 16.12 days (range, 11-26). The median time of platelet engraftment was 28.30 days (range, 13-143). The cumulative incidence of grade II acute GVHD (aGVHD) at day +100 was 32.00 ± 0.91%. No one had grade III-IV aGVHD at day +100. The cumulative incidence of total chronic GVHD was 28.00 ± 0.85%. The overall survival was 71.78 ± 9.05% at a median follow-up of 42.08 months (range, 2.67-104). Promisingly, the protocol yielded a similar curative effect in both young and adult SAA patients. CONCLUSIONS: The authors' data suggest that co-transplantation of HLA-haploidentical HSCs and UC-MSCs may provide an effective and safe treatment for adult SAA.

Exosomes originating from MSCs stimulated with TGF-ß and IFN-γ promote Treg differentiation.

Mesenchymal stem cells (MSCs) have been approved as a cellular drug for the treatment of a variety of immune-related diseases by the government of many countries'. Previous investigations, including ours, have shown that exosomes secreted by MSCs (MSC-ex) are one of the main factors responsible for the therapeutic effect of MSCs. However, the immune modulation activities and the contents of MSC-ex derived from cells under different incubation conditions differ dramatically. Therefore, the optimal way to ensure effectiveness is by identifying and preparing MSC-ex with confirmed potent immunosuppressive activity. The aim of this study was to investigate and analyze the composition and function of MSC-ex secreted by MSCs stimulated by different cytokines to obtain exosomes with more potent immunosuppressive activity. To achieve this aim, umbilical cord-derived MSCs were treated with PBS, TGF-ß, IFN-γ, or TGF-ß plus IFN-γ for 72 hr. Then, exosomes were isolated from the culture supernatants. Common exosome markers, such as CD9, CD63, and CD81, were detected and analyzed by FCM. At the same time, the TGF-ß, IFN-γ, IDO, and IL-10 content in exosomes was detected, and the influence of exosmes from defferent groups on the induction of mononuclear cell transformation into Tregs was analyzed via FCM. Our results show that the TGF-ß combined with IFN-γ exosome group more effectively promoted the transformation of mononuclear cells to Tregs, and the analysis showed that IDO may play an important role. This study might provide a novel strategy to treat GVHD as well as other immune-associated disorders.

Hepatocyte growth factor enhances the inflammation-alleviating effect of umbilical cord-derived mesenchymal stromal cells in a bronchiolitis obliterans model.

BACKGROUND AIMS: Specific and effective therapy for prevention or reversal of bronchiolitis obliterans (BO) is lacking. In this study, we evaluated the therapeutic effect of hepatocyte growth factor (HGF) gene modified mesenchymal stromal cells (MSCs) on BO. METHODS: A mouse model of experimental BO was established by subcutaneously transplanting the tracheas from C57BL/6 mice into Balb/C recipients, which were then administered saline, Ad-HGF-modified human umbilical cord-MSCs (MSCs-HGF) or Ad-Null-modified MSCs (MSCs-Null). The therapeutic effects of MSCs-Null and MSCs-HGF were evaluated by using fluorescence-activated cell sorting (FACS) for lymphocyte immunophenotype of spleen, enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (rt-PCR) for cytokine expression, and histopathological analysis for the transplanted trachea. RESULTS: The histopathologic recovery of allograft tracheas was improved significantly after MSCs-Null and MSCs-HGF treatment and the beneficial effects were particularly observed in MSCs-HGF-treated mice. Furthermore, the allo-transplantation-induced immunophenotype disorders of the spleen, including regulatory T (Treg), T helper (Th)1, Th2 and Th17, were attenuated in both cell-treated groups. MSCs-HGF treatment reduced expression and secretion of inflammation cytokines interferon-gamma (IFN-γ), and increased expression of anti-inflammatory cytokine interleukin (IL)-4 and IL-10. It also decreased the expression level of the profibrosis factor transforming growth factor (TGF)-ß. CONCLUSION: Treatment of BO with HGF gene modified MSCs results in reduction of local inflammation and promotion in recovery of allograft trachea histopathology. These findings might provide an effective therapeutic strategy for BO.

SENP1 inhibition induces apoptosis and growth arrest of multiple myeloma cells through modulation of NF-κB signaling.

SUMO/sentrin specific protease 1 (Senp1) is an important regulation protease in the protein sumoylation, which affects the cell cycle, proliferation and differentiation. The role of Senp1 mediated protein desumoylation in pathophysiological progression of multiple myeloma is unknown. In this study, we demonstrated that Senp1 is overexpressed and induced by IL-6 in multiple myeloma cells. Lentivirus-mediated Senp1 knockdown triggers apoptosis and reduces viability, proliferation and colony forming ability of MM cells. The NF-κB family members including P65 and inhibitor protein IkBα play important roles in regulation of MM cell survival and proliferation. We further demonstrated that Senp1 inhibition decreased IL-6-induced P65 and IkBα phosphorylation, leading to inactivation of NF-кB signaling in MM cells. These results delineate a key role for Senp1in IL-6 induced proliferation and survival of MM cells, suggesting it may be a potential new therapeutic target in MM.

Bone marrow mesenchymal stem cell-derived microvesicles protect rat pheochromocytoma PC12 cells from glutamate-induced injury via a PI3K/Akt dependent pathway.

Studies have suggested that mesenchymal stem cells (MSCs) can protect neuronal cells from excitotoxicity, but the underlying mechanisms are still remaining elusive. In the study, we show that microvesicles released by rat bone marrow-derived MSCs (rBMSC-MVs) protect rat pheochromocytoma PC12 cells from glutamate-induced excitotoxicity. BMSC-MVs upregulate Akt phosphorylation and Bcl-2 expression, downregulate Bax expression, and reduce the cleavage of caspase-3 in glutamate-treated PC12 cells. Such protective effects are partially abrogated by inhibiting PI3K, indicating that rBMSC-MVs act via the PI3K/Akt pathway. Transplantation of rBMSC-MVs may, therefore, be a promising strategy to treat cerebral injury or some other neuronal diseases involving excitotoxicity.

Haploidentical Hematopoietic Stem Cell Transplantation for Paediatric Patients with X-linked Lymphoproliferative Syndrome.

The aim of this study was to investigate the prognostic factors of haploid hematopoietic stem cell transplantation in the treatment of X-linked lymphoproliferative syndrome. Seven children with X-linked lymphoproliferative syndrome diagnosed by XIAP gene analysis were enrolled. The conditioning regimens were tolerated in all seven patients, and the median time of neutrophil engraftment was 10 days (8-13 days), and that of platelet engraftment was 21 days (14-24 days). STR-PCR analysis on the peripheral blood cells showed complete donor origins. Four cases developed Grade I acute graft versus host disease (aGVHD), one developed Grade III aGVHD (intestinal tract), and two cases had limited chronic GVHD. Four cases had cytomegalovirus (CMV) reactivation, and two cases had Epstein-Barr virus (EBV) reactivation. One case was diagnosed as pneumocystosis, and thrombotic microangiopathy (TMA) occurred in three cases. During the follow-up period (median time of 42 months), one patient died of TMA and six patients survived. Statistical analysis showed that the status of disease remission and the positive result of virus in blood before transplantation were independent prognostic factors. Haplo-HSCT might be a curative option for children with refractory X-linked lymphoproliferative syndrome. Low-intensity conditioning regimens may reduce transplant-related mortality and improve overall survival.

Hematopoietic stem cell transplantation with umbilical cord multipotent stromal cell infusion for the treatment of aplastic anemia--a single-center experience.

BACKGROUND AIMS: The purpose of this study was to observe the outcome of co-transfusion of umbilical cord multipotent stromal cells (UC-MSC) and allogeneic hematopoietic stem cells in the treatment of heavily-transfused patients with severe aplastic anemia. METHODS: Of the 22 patients, eight cases received haploidentical hematopoietic stem cells from granulocyte colony-stimulating factor-primed bone marrow and peripheral blood grafts; the other patients received granulocyte colony-stimulating factor-mobilized peripheral blood grafts from human leukocyte antigen-matched related (six cases) and unrelated donors (eight cases). MSCs were intravenously infused at a mean dose of 1.2 × 10(6)/ kg (range, 0.27-2.5 × 10(6)/kg). Fludarabine-based conditioning was conducted, and graft-versus-host disease prophylaxis containing cyclosporine A, methotrexate and mycophenolate mofetil with or without addition of anti-CD25 monoclonal antibody was performed. Hematopoietic engraftment, the occurrence of graft-versus-host disease (GVHD) and infections and overall survival were documented. RESULTS: All patients had rapid engraftment; mean time for neutrophil and platelet recovery was 13.95 d and 20.27 d, respectively. No acute toxicity associated with UC-MSC transfusion was observed. Acute GVHD developed in seven cases (grade I-II), and none had development of chronic GVHD. Cytomegalovirus reactivation was observed in 11 cases. One patient died of pulmonary complication 6 months after transplantation. Twenty-one patients are currently alive, at a median follow-up of 15 months; they are transfusion-independent and reached full donor chimerism at the time of reporting. CONCLUSIONS: UC-MSC infusion might be an alternative option to promote hematopoietic engraftment and reduce the occurrence of GHVD in hematopoietic stem cell transplantation in the treatment of heavily transfused patients with severe aplastic anemia.

Clinical analysis of the treatment of spinal cord injury with umbilical cord mesenchymal stem cells.

BACKGROUND AIMS: The purpose of this study was to observe the clinical effect and safety of umbilical cord mesenchymal stem cells (UC-MSCs) in treating spinal cord injury (SCI) by intrathecal injection. METHODS: From January 2008 to October 2010, we treated 22 patients with SCI with UC-MSCs by intrathecal injection; dosage was 1 × 10(6) cells/kg body weight once a week given four times as a course. Four patients received two courses, one patient received three courses and all other patients received one course. American Spinal Injury Association scoring system and International Association of Neurorestoratology Spinal Cord Injury Functional Rating Scale were used to evaluate neural function and ability to perform activities of daily living. RESULTS: Treatment was effective in 13 of 22 patients; nine patients had no response. Among patients with incomplete SCI, the response to treatment was 81.25%; there was no response to treatment among six patients with complete SCI. Five patients with a response to treatment received two to three courses of therapy, and effects in these patients were further enhanced. In most patients in whom treatment was effective, motor or sensory functions, or both, were improved, and bowel and bladder control ability was improved. In 22 patients 1 month after therapy, algesia, tactile sensation, motion and activity of daily living scale were significantly improved (P < 0.01). During therapy, common adverse effects were headache (one case) and low back pain (one cases); these disappeared within 1-3 days. No treatment-related adverse events occurred during a follow-up period ranging from 3 months to 3 years. CONCLUSIONS: UC-MSC therapy by intrathecal injection is safe and can improve neurologic function and quality of life in most patients with incomplete SCI.

Not all side population cells contain cancer stem-like cells in human gastric cancer cell lines.

INTRODUCTION: Side population (SP) cells may play a crucial role in tumorigenesis and the recurrence of cancer. Many kinds of cell lines and tissue have demonstrated presence of SP cells including different gastric cancer cell lines. However, is that true all SP cells contain cancer stem-like cells in gastric cancer cell lines? MATERIALS AND METHODS: MKN-45 and BGC-823 cells labeled with Hoechst 33342 were chosen to obtain SP cells, then characterized the cancer stem-like properties of SP cells both in vitro and in vivo. Five stemness-related genes expression profiles, including OCT-4, SOX-2, NANOG, CD44 and ATP-binding cassette transporters gene ABCG-2, were tested in SP and MP cells using quantitative real-time RT-PCR. Western blot was chosen to show the difference of protein expression between SP and MP cells. When inoculated into non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, SP cells from MKN-45 showed higher tumorigenesis tendency than MP cells, but SP cells from BGC-823 showed same tumorgenesis tendency as MP cells. CONCLUSION: SP cells from MKN-45 possess cancer stem cell properties and proved that they were gastric cancer stem-like cells. SP cells from BGC-823 didn't possess cancer stem cell properties and proved that not all SP cells contain cancer stem-like cells in gastric cancer cell lines.

[Recent Progress on Pharmaceutical Properties of Extracellular Vesicles from Mesenchymal Stem Cells--Review].

Mesenchymal stem cells (MSCs) have been officially approved in many countries to treat graft-versus-host disease, autoimmune disorders and those associated with tissue regeneration after hematopoietic stem cell transplantation. Studies in recent years have confirmed that MSC acts mainly through paracrine mechanism, in which extracellular vesicles secreted by MSC (MSC-EV) play a central role. MSC-EV has overwhelming advantages over MSC itself in the setting of adverse effects in clinical application, indicating that MSC-EV might take the place of its parent cells to be a potentially therapeutic tool for "cell-free therapy". The pharmaceutical properties of MSC-EV largely depend upon the practical and optimal techniques including large-scale expansion of MSC, the modification of MSC based on the indications and the in vivo dynamic features of MSC-EV, and the methods for preparing and harvesting large amounts of MSC-EV. The recent progresses on the issues above will be briefly reviewed.

Second Allogeneic Hematopoietic Stem Cell Transplantation for Hemophagocytic Syndrome with Engraftment Failure.

This study aims to assess the efficacy of second allogeneic hemopoietic stem cell transplantation (allo-HSCT) for treating hemophagocytic syndrome with first engraftment failure. Among a total of 35 patients who underwent allo-HSCT between June 2015 and July 2021 for HLH, 10 patients who underwent a second HSCT following graft rejection were retrospectively analyzed. Various factors, such as the treatment course and outcome, the remission status, donor selection, and the conditioning regimen of patients before second allo-HSCT, were scrutinized for transplant-related complications and transplant-related mortality, as well as transplant outcomes. All the subjects have achieved complete donor engraftment, in which the neutrophils and platelets engraftment occurred in a median time of 12 d (range 10-19 d) and 24 d (range 11-97 d), respectively. Among the selected subjects, 20% of patients are diseased due to transplant-related thrombotic microangiopathy. Further, 90% of patients are diagnosed with aGVHD, in which 3 of them with grade I aGVHD, one patient with grade II aGVHD, two patients with grade III GVHD, and three patients with localized chronic GVHD. Moreover, 70% of patients showed signs of combined viral infections. Despite the complex symptoms, the overall survival rate is around 80%, with transplant-related mortality and the incidence of post-transplant GVHD of 20% and 60%, respectively. Together, our findings indicated that the second allo-HSCT showed great potential in treating hemophagocytic syndrome with engraftment failure.

Progression-Free Survival of a Patient with Advanced Hepatocellular Carcinoma Treated with Adoptive Cell Therapy Using Natural Killer Cells: A Case Report.

Adoptive cell therapy (ACT) is a promising treatment that is considered safe and efficient. Natural killer (NK) cells play an important role in the innate immune system and destroy target cells such as tumor cells without prior sensitization. Here, we report a 59-year-old man with advanced diffuse hepatocellular carcinoma (HCC) who underwent 17 courses of NK cell treatment from March 2017 to July 2018. Although he presented with progressive disease, his hydrothorax and ascites decreased, and his state of mind, appetite and quality of life were markedly improved after treatment versus at admission. To date, his survival time is >48 months. Here, we provide evidence that NK cell adoptive therapy has no adverse effects, enhances immune function, and improves the quality of life of patients with HCC.

[Clinical Safety of NK Cell in the Prevention of Leukemia Relapse Post-transplantation and in Treatment of the Elderly Leukemia Patients].

OBJECTIVE: To observe the safety of donor NK cell infusions in the settings of hematopoietic stem cell transplantation and after consolidation chemotherapy in elderly patients with acute myeloid leukemia (AML). METHODS: Forty patients with AML were included, in which 21 patients aged over 60 years were at the stage of complete remission (CR) and 19 patients that received allogeneic hematopoietic stem cell transplantation (allo-HSCT). Mononucleated cells were isolated from peripheral blood from the donors (for allo-HSCT) or healthy immediate family members (elderly AML). The cells were seeded into the flasks pre-coated with NK cell specific activators, and expanded in media containing recombinant human IL-15 and IL-2 for 14 days. The cells were transfused intravenously after the identification of quality control. Trypan blue exclusion test was used for the determination of cell viability and counting. Flow cytometry analysis was performed to assess the surface antigenic profile. Seventy-eight infusions of the cell products were received by the elderly patients with AML after consolidation chemotherapy, 11 infusions were received by the patients during allo-HSCT and 32 infusions 3 moths after transplantation. The safety of cell therapy, body temperature, blood pressure and other indexes were observe during and 48 hours after cell transfusion. Meanwhile, the occurrence and severity of acute graft-versus-host disease (GVHD) were documented. RESULTS: Flow cytometry analysis showed that the proportion of NK cells (CD3-CD56+) in the mononucleated cells before culture was (14.10±4.22)% (n=121), and the proportion increased dramatically up to (87.29±8.75)% (n=121) after culture for 14 days, the number of NK cells increased to 753.47±140.13 times (n=121). The doses of the infused NK cells was (7.58±2.50)×107/kg per infusion. Moderate fever occurred in three cases after multiple infusions, and the temperature restored to normal on the same day after treatment. Fever was observed in one patient after every infusion of four times in total. The temperature reached to 38.5-39.0 ℃ and returned to normal within 1-2 hours after adequate antipyretic treatment, and then there was no discomfort. No GVHD was observed in the elderly AML patients, while 6 cases that received allo-HSCT developed moderate acute GVHD, among them grade I in 5 cases and grade II in 1 case. No other severe toxicities were observed. CONCLUSION: NK cell products with a high-purity could be obtained by ex vivo expansion with this protocol. The transfusion of these expanded cells is generally safe in the elderly patients with AML that have received chemotherapy or patients that received hematopoietic stem cell transplantation.

Infusion of haploidentical HSCs combined with allogenic MSCs for the treatment of ALL patients.

Although haploidentical stem cell transplantation (haplo-HSCT) offers almost all acute lymphoblastic leukaemia (ALL) patients an opportunity for immediate transplantation, it exhibits a higher incidence of graft failure and graft versus host disease (GVHD). Mesenchymal stem cells (MSCs) are characterised by their haematopoiesis-promoting and immunomodulatory capacity. Thus, we designed a combination of haplo-HSCT and MSCs for ALL patients. ALL patients (n = 110) were given haploidentical HSCs combined with allogenic MSCs, and ALL patients without MSC infusion (n = 56) were included as controls. The 100-day cumulative incidences of grade ≥2 acute GVHD (aGVHD) and grade ≥3 aGVHD were 40.00% and 9.09% compared to 42.32% (P = 0.79) and 22.79% (P = 0.03) in patients without MSC infusion, respectively. The 3-year cumulative incidences of chronic GVHD (cGVHD) and extensive cGVHD were 22.27% and 10.27% compared to 32.14% (P = 0.19) and 22.21% (P = 0.04) in patients without MSC infusion, respectively. No significant differences in the 3-year relapse incidence, nonrelapse mortality, leukaemia-free survival or overall survival in groups with and without MSC cotransplantation were observed. Multivariate analysis showed that MSC infusion contributed to a lower risk of developing extensive cGVHD. Our data suggested that haplo-HSCT combined with MSCs may provide an effective and safe treatment for ALL patients.

[Investigating the treatment of silicosis with autologous bone marrow-derived mesenchymal stem cells].

OBJECTIVE: To explore the safety and curative effects of autologous bone marrow-derived mesenchymal stem cells (BMSCs) in the treatment of silicosis. METHODS: The protocol was approved by the Ethics Committee of the hospital, and ten patients with silicosis who had given written consent were enrolled in this study. BMSCs isolated from 100 ml of bone marrow for each case were purified and cultured. In each case the 3rd generation of qualified BMSCs (5 × 10(7)) were intravenously administered weekly for 3 weeks. Three cases among 10 patients were treated with BMSCs modified by hepatocyte growth factor (HGF) gene. The clinical symptoms, chest films, chest CT, pulmonary functions, T cells, serum IgG and ceruloplasmin (CP) were observed in 6 or 9 months after treatment. RESULTS: No obvious sub-effect was observed in cases treated with BMSCs, the clinical symptoms (such as cough, sputum and chest tightness) basically disappeared in 9 months after treatment. Pulmonary function tests showed that FVC increased from 71.2% ± 17.0% to 84.0% ± 10.9% (P < 0.01) and FEV1.0 increased from 67.5% ± 17.7% to 80.6% ± 14.9% (P < 0.01). The levels of serum CP and IgG significantly decreased (P < 0.01). Further, the chest films and CT in cases treated with autologous BMSCs modified by HGF gene were improved to different extent. CONCLUSION: Treatment with autologous BMSCs modified by HGF gene exhibit a beneficial effect on silicosis.

[Hepatocyte growth factor combined with autologous bone marrow mesenchymal stem cell transplantation for treatment of silicosis].

OBJECTIVE: To evaluate the potential role of hepatocyte growth factor (HGF) combined with bone marrow mesenchymal stem cells (BMSC) autograft for the treatment of silicosis. METHODS: Bone marrow (100 ml) was aspirated from a severe silicosis patient. BMSCs isolated, purified and cultured in vitro. When BMSC came to 70% confluence at passage 3, the culture medium was added liposomes (lipo2000) and plasmid-HGF (p-HGF) and cultured for 2 d. HGF-MSCSs (5 × 10(7) cells) were resuspended in 50 ml 0.9% sodium chloride (NS) and infused Intravenous drip at 3 consecutive times (once a week). Clinical follow-up were performed before and after treatment: (1) pulmonary high-kV X-ray, chest CT examination; (2) pulmonary function test; (3) determination of serum ceruloplasmin. RESULTS: The symptoms such as coughing, chest tightness disappeared at 12 months after treatment. Pulmonary function tests showed significant changes after treatment: forced vital capacity (FVC) increased from 64.6% to 81.0%, forced expiratory volume in one second (FEV(1.0)) increased from 68.7% to 90.1%, 1 second rate (FEV(1.0)/FVC%) reduced from 111.6% to 107.1%, the maximum mid-expiratory flow (FEF(25%∼75%) decreased from 100.2% to 94.6%, forced expiratory vital capacity 75% of the moment bit of gas flow (MEF(75%)) increased from 99.2% to 113.5%, forced expiratory vital capacity 50% of the moment bit of gas flow (MEF(50%)) increased from 125.3% to 130.2%, forced expiratory vital capacity 25% of the moment bit of gas flow (MEF(25%)) reduced from 86.9% to 71.7%; serum ceruloplasmin levels decreased from 690 mg/L to 180.6 mg/L; lung high-kV X-ray at 1st review showed that diffuse lung nodules had been absorbed and getting smaller than before treatment; chest CT showed that the distribution and number of small nodules at double lung fields decreased than before treatment. CONCLUSION: HGF combined with BMSC transplantation may have some potential role for the treatment of silicosis patients.

A study of human leukocyte antigen-haploidentical hematopoietic stem cells transplantation combined with allogenic mesenchymal stem cell infusion for treatment of severe aplastic anemia in pediatric and adolescent patients.

The clinical applications of human leukocyte antigen (HLA) haploidentical hematopoietic stem cells transplantation (haplo-HSCT) have offered most of the young severe aplastic anemia (SAA) patients an opportunity to accept curative therapy at the early stage of bone marrow lesions. However, the outcome of juvenile SAA patients received haplo-HSCT remain to be improved due to high incidence of graft failure and graft vs host disease (GVHD). Mesenchymal stem cells (MSCs) have been characterized by their hematopoiesis-supporting and immunomodulatory properties. In the current study, we designed a combination of haplo-HSCT with allogenic MSC for treatment of SAA in pediatric and adolescent patients and evaluated its effects. Juvenile patients (<18 years) with SAA (n = 103) were given HLA-haploidentical HSC combined with allogenic MSC after a conditioning regimen consisting of busulfan, cyclophosphamide, fludarabine, and antithymocyte globulin and an intensive GVHD prophylaxis, including cyclosporine, short-term methotrexate, mycophenolate mofetil, and basiliximab. Neutrophil engraftment was achieved in 102 of 103 patients in a median time of 14.3 days (range 9-25 days). The median time of platelet engraftment was 25.42 days (range 8-93 days). The cumulative incidence of II-IV acute GVHD at day +100 was 26.32% ± 0.19% and III-IV acute GVHD was 6.79% ± 0.06% at day +100, respectively. The cumulative incidence of chronic GVHD was 25.56% ± 0.26%. The overall survival was 87.15% ± 3.3% at a median follow-up of 40 (1.3-98) months. Our data suggest that cotransplantation of HLA-haploidentical HSC and allogenic mesenchymal stem cell may provide an effective and safe treatment for children and adolescents with SAA who lack matched donors.

Co-transfusion of haplo-identical hematopoietic and mesenchymal stromal cells to treat a patient with severe aplastic.

A 3-year-old girl with severe aplastic anemia (SAA) that was unresponsive to steroid, cyclosporine and filgrastim treatments received bone marrow (BM) mesenchymal stromal cells (MSC; 1.25 x 10(6)/kg), granulocyte colony-stimulating factor (G-CSF)-mobilized BM and peripheral blood stem cell grafts from her father. Prior to stem cell transplantation, she had experienced repeated bacterial infections and received 44 blood transfusions during 8 months after diagnosis. The conditioning regimen consisted of fludarabine, cyclophosphamide and busulfan, and prophylaxis of acute graft-versus-host disease (GvHD) was performed by administration of anti-CD25 monoclonal antibody, cyclosporine A, methotrexate, mycophenolate mofetil and anti-thymocyte globulin. The patient achieved rapid hematopoietic engraftment of donor origin and no acute or chronic GvHD was observed. She is now alive with a good performance status, and the dose of cyclosporine A is being tapered. The novel regimen described here might be a suitable option for children with SAA who lack immediate access to HLA-matched sources.

[Establishment of A Novel Method to Activate and Expand Human NK Cells Ex Vivo].

OBJECTIVE: To develop a new method to activate and expand human NK cells ex vivo by using sodium hyaluronate as a major activating agent and to explore its related mechanism. METHODS: Mononuclear cells were isolated from 3 samples of peripheral blood from three healthy donors. New NK cell culture method and the control method were used to culture NK cells from each samples separately for 14 days. Flow cytometry was used to analyze the ratio of NK cells and CD69 expression. To measure the in vitro cytotoxicity of NK cells cultured by the two methods, the K562 cells were used as the targeting cells and flow cytometry combined with CFSE marker was used as the testing method. RESULTS: After culturing for 14 days, the number of NK cells obtained by new culture method for NK cells expanded by 188.63±3.83 times while the number of NK cells cultured by control method expanded by 152.77±5.77 times. The ratio of NK cells in new cell culture method was above 90%, while the ratio of NK cells in control method was about 70%. The ratio of CD69+ NK cells in new cell culture method was 32.37%±3.22%, while the ratio of CD69+ NK cells in control method was 17.29%±3.79%. The results of cytotoxicity experiment in vitro showed that NK cells cultured by the new method had a higher killing ability to the target cells as compared with NK cells cultured by the control method. CONCLUSION: New NK cell culture method using sodium hyaluronate as a major activating agent can expand NK cells more efficiently as compared with the cells cultured by control method, which may be related to the direct and/or indirect activation of sodium hyaluronate to NK cells, further causing the dominant expansion of the NK cells.

Tumor necrosis factor α in aGVHD patients contributed to the impairment of recipient bone marrow MSC stemness and deficiency of their hematopoiesis-promotion capacity.

BACKGROUND: Though accumulated evidence has demonstrated visceral organ involvement in acute graft-versus-host disease (aGVHD), how aGVHD influences the bone marrow (BM) niche and the reconstitution of hematopoiesis post-hematopoietic stem cell transplantation remains largely unknown. METHODS: In the current study, the cell morphology, immunophenotype, multi-differentiation capacity, self-renewal capacity, and hematopoiesis promotion of the MSCs from aGVHD and non-aGVHD patients were investigated. Additionally, the stemness and hematopoiesis-promoting property of healthy donor-derived MSCs were evaluated in the presence of BM supernatant from aGVHD patients. Mechanistically, antibodies targeting inflammatory cytokines involved in aGVHD were added into the MSC culture. Furthermore, a recombinant human tumor necrosis factor (TNF-α) receptor-Ig fusion protein (rhTNFR:Fc) was used to protect healthy donor-derived MSCs. Moreover, mRNA sequencing was performed to explore the underlying mechanisms. RESULTS: The aGVHD MSCs exhibited morphological and immunophenotypic characteristics that were similar to those of the non-aGVHD MSCs. However, the osteogenic and adipogenic activities of the aGVHD MSCs significantly decreased. Additionally, the colony formation capacity and the expression of self-renewal-related genes remarkably decreased in aGVHD MSCs. Further, the hematopoiesis-supporting capacity of aGVHD MSCs significantly reduced. The antibody neutralization results showed that TNF-α contributed to the impairment of MSC properties. Moreover, rhTNFR:Fc exhibited notable protective effects on MSCs in the aGVHD BM supernatants. The mRNA sequencing results indicated that the TNF-α pathway and the Toll-like receptor pathway may be activated by TNF-α. CONCLUSIONS: Thus, our data demonstrate MSCs as cellular targets of aGVHD and suggest a potential role of TNF-α blockage in maintaining the BM niche of aGVHD patients.