non-MSC Group Research Articles

Mesenchymal stromal cell treatment improves outcomes in children with pneumonia post-hematopoietic stem cell transplantation: a retrospective cohort study

BackgroundHematopoietic stem cell transplantation (HSCT) is a standard therapy strategy for most malignant disorders in children. However, transplant-related pneumonia remains a major therapy challenge and mesenchymal stromal cells (MSCs) are rarely reported in HSCT-related pneumonia. The aim of our study was to assess the efficacy of MSC for HSCT-related pneumonia in children.MethodsWe retrospectively retrieved HSCT-related (severe and non-severe) pneumonia cases (aged < 18 years), which underwent MSC treatment (MSC group) or non-MSC treatment (non-MSC group) in Guangzhou Women and Children’s Medical Center, from December 2017 to December 2019. We investigated outcomes of the two different treatments among severe cases and non-severe cases, respectively. The primary endpoints were differences in overall cure rate and time to cure between MSC and non-MSC groups. The secondary endpoints were 180-day overall survival and cumulative cure rate.ResultsFinally, 31 severe pneumonia cases (16 in MSC group, 15 in non-MSC group) and 76 non-severe cases (31 in MSC group, 45 in non-MSC group) were enrolled in this study. Among severe pneumonia cases, overall cure rate in MSC group was significant higher than that in non-MSC group (12[75.0%] vs. 5[33.3%]; OR = 6.00, 95% CI [1.26–28.5]; p = 0.020); the time (days) to cure in MSC group was dramatically reduced compared with that in non-MSC group (36 [19–52] vs. 62 [42–81]; OR = 0.32, 95% CI [0.12–0.88]; p = 0.009); the 180-day overall survival in MSC group was better than that in non-MSC group (74.5% [45.4–89.6] vs. 33.3% [12.2–56.4]; p = 0.013). Among non-severe pneumonia cases, the time (days) to cure in MSC group was notably decreased compared with that in non-MSC group (28 [24–31] vs. 33 [26–39]; OR = 0.31, 95% CI [0.18–0.56]; p = 0.003). Compared with non-MSC group, MSC-treated patients achieved significant improvements of cumulative cure rate not only in severe pneumonia cases (p = 0.027), but also in non-severe cases (p < 0.001).ConclusionsThis study revealed that MSC treatment could contribute to improving outcomes in children with pneumonia post-HSCT, especially in severe cases. These findings suggest MSC treatment as a promising therapy for HSCT-related pneumonia in children.

Combination of Haploidentical Hematopoietic Stem Cell Transplantation with Umbilical Cord-Derived Mesenchymal Stem Cells in Patients with Severe Aplastic Anemia: A Retrospective Controlled Study

Objective:We retrospectively compared the outcomes of patients with severe aplastic anemia (SAA) who received haploidentical hematopoietic stem cell transplantation (haplo-HSCT) combined or not combined with umbilical cord-derived mesenchymal stem cells (UC-MSCs).Materials and Methods:A total of 101 patients with SAA were enrolled in this study and treated with haplo-HSCT plus UC-MSC infusion (MSC group, n=47) or haplo-HSCT alone (non-MSC group, n=54).Results:The median time to neutrophil engraftment in the MSC and non-MSC group was 11 (range: 8-19) and 12 (range: 8-23) days, respectively (p=0.049), with a respective cumulative incidence (CI) of 97.82% and 97.96% (p=0.101). Compared to the non-MSC group, the MSC group had a lower CI of chronic graft-versus-host disease (GVHD) (8.60±0.25% vs. 24.57±0.48%, p=0.048), but similar rates of grades II-IV acute GVHD (23.40±0.39% vs. 24.49±0.39%, p=0.849), grades III-IV acute GVHD (8.51±0.17% vs. 10.20±0.19%, p=0.765), and moderate-severe chronic GVHD (2.38±0.06% vs. 7.45±0.18%, p=0.352) were observed. The estimated 5-year overall survival (OS) rates were 78.3±6.1% and 70.1±6.3% (p=0.292) while the estimated 5-year GVHD-free, failure-free survival (GFFS) rates were 76.6±6.2% and 56.7±6.9% (p=0.045) in the MSC and non-MSC groups, respectively.Conclusion:In multivariate analysis, graft failure was the only adverse predictor for OS. Meanwhile, graft failure, grades III-IV acute GVHD, and moderate-severe chronic GVHD could predict worse GFFS. Our results indicated that haplo-HSCT combined with UC-MSCs infusion was an effective and safe option for SAA patients.

Effects and long-term follow-up of using umbilical cord blood-derived mesenchymal stromal cells in pediatric patients with severe BK virus-associated late-onset hemorrhagic cystitis after unrelated cord blood transplantation.

This is a retrospective study to evaluate the efficacy and safety of umbilical cord blood-derived mesenchymal stromal cells (MSCs) for the treatment of pediatric patients with severe BK virus-associated late-onset hemorrhagic cystitis (BKV-HC) after unrelated cord blood transplantation (UCBT). Thirteen pediatric patients with severe BKV-HC from December 2013 to December 2015 were treated with MSCs. The number of MSCs transfused in each session was 1×106 /kg once a week until the symptoms improved. The median follow-up time was 1432 (89-2080) days. The median frequency of MSC infusion was 2 (1-3), with eight cured cases and five effective cases; the total efficacy rate was 100%. The copy number of urine BKV DNA was 4.43 (0.36-56.9) ×108 /mL before MSC infusion and 2.67 (0-56.3) ×108 /mL after MSC infusion; the difference was not significant (P=.219). There were no significant differences in the overall survival, disease-free survival, and the incidence of relapse and acute and chronic graft-versus-host disease between the MSC infusion group and non-MSC infusion group. There was also no significant difference in the cytomegalovirus, Epstein-Barr virus (EBV), and fungal and bacterial infection rates between the two groups. Although umbilical cord blood-derived MSCs do not reduce the number of BKV DNA copies in the urine, the cells have a high efficacy rate and minimal side effects in treating severe BKV-HC after UCBT among pediatric patients. MSCs do not affect the rates of relapse, long-term infection, or survival of patients with leukemia.

Efficacy of Mesenchymal Stem Cells in Bronchiolitis Obliterans Syndrome after Allogeneic HSCT: A Multicenter Prospective Cohort Study

Background: Bronchiolitis obliterans syndrome (BOS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a devastating complication with limited therapeutic options. We aimed to assess the efficacy and safety of mesenchymal stem cells (MSCs) in BOS after allo-HSCT. Methods: Eighty-one allo-HSCT recipients with BOS diagnosed within 6 months were enrolled in this multicenter prospective cohort study. The choice of prednisone and azithromycin combined with or without MSCs was based on patient preferences (MSC n=49, non-MSC n=32). The primary endpoint was response rate at 3 months, defined as the proportion of patients achieving FEV1 improvement or steroid sparing. This trial was registered at ClinicalTrials.gov, NCT02543073. Results: Response rate was 35/49 patients (71%, 95% confidence intervals [CI] 59 to 84%) (FEV1 improvement n=10, steroid sparing n=25) and 14/32 (44%, 95% CI 27 to 61%) (FEV1 improvement n=3, steroid sparing n=11) in the MSC and non-MSC group, respectively (p=0.013). The adjusted odds ratio of response in the MSC group compared with the non-MSC group was 3.32 (95% CI 1.21-9.11; p=0.02). The addition of MSCs was associated with a better difference for change in FEV1 rate of decline, compared to non-MSC group (53 ml/months, 2 to 103; p=0.040). The 3-year overall survival post-diagnosis was 70.6% (95% CI 55.9 to 85.3%) and 58.2% (95% CI 36.1 to 78.5%) in the MSC and non-MSC group, respectively (p=0.21). Clinical improvement was accompanied by a significant increase of interleukin (IL)-10-producing CD5+ B cells. The incidences of infection and leukemia relapse were no significant difference between two groups. Multiple infusions of MSCs were well-tolerated with no serious adverse events. Interpretation: MSCs might be an effective and safe therapy for BOS patients after allo-HSCT. Our study strengthens evidence for clinical practice of MSC therapy in BOS. These data also offer insight into potential biological mechanisms of MSC treatment and support further investigation in larger randomized controlled trials. Disclosures No relevant conflicts of interest to declare.

The Efficacy of Mesenchymal Stem Cells in Bronchiolitis Obliterans Syndrome after Allogeneic HSCT: A Multicentre Prospective Cohort Study

Background: Bronchiolitis obliterans syndrome (BOS) after allo-HSCT is a devastating complication with limited therapeutic options. We aimed to assess the efficacy and safety of mesenchymal stem cells (MSCs) in BOS after allo-HSCT. Methods: Eighty-one allo-HSCT recipients with BOS diagnosed within 6 months were enrolled in this multicentre prospective cohort study. The choice of prednisone and azithromycin combined with or without MSCs was based on patient preferences (MSC n=49, non-MSC n=32). The primary endpoint was response rate at 3 months, defined as the proportion of patients achieving FEV1 improvement or steroid sparing. Findings: Response rate was 35/49 patients (71%, 95% CI 59 to 84%) and 14/32 (44%, 27 to 61%) in MSC and non-MSC group, respectively (p=0*013). The addition of MSCs was associated with a better difference for change in FEV1 rate of decline, compared to non-MSC group (53 ml/months, 2 to 103; p=0*040). The 3-year overall survival post-diagnosis was 70*6% (55*9 to 85*3%) and 58*2% (36*1 to 78*5%) in MSC and non-MSC group, respectively (p=0*21). Clinical improvement was accompanied by a significant increase of interleukin (IL)-10-producing CD5+B cells. Infections and leukemia relapse were no significant difference between two groups. MSCs were well-tolerated with no serious adverse events. Interpretation: MSCs might be an effective and safe therapy for BOS after allo-HSCT. These data also offer insight into potential biological mechanisms of MSC treatment and support further investigation in larger randomized controlled trials. Our study strengthens evidence for clinical practice of MSC therapy in BOS. Trial Registration: This trial is registered with ClinicalTrials.gov, NCT02543073. Funding Statement: This study was supported by the National Key R&D Program of China (2017YFA105500 and 2017YFA105504), the National Natural Science Foundation of China (81770190 and 81700176), the Health Collaborative Innovation Major Projects of Guangzhou City (201508020254), the Science and Technology Planning Project of Guangdong Province (2014B020226004). Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: The protocol was approved by institutional review board at each centre. Written informed consents were obtained from all participants in accordance with the Helsinki Declaration.

Allogeneic mesenchymal stem cells as induction therapy are safe and feasible in renal allografts: pilot results of a multicenter randomized controlled trial

BackgroundKidneys from deceased donors are being used to meet the growing need for grafts. However, delayed graft function (DGF) and acute rejection incidences are high, leading to adverse effects on graft outcomes. Optimal induction intervention should include both renal structure injury repair and immune response suppression. Mesenchymal stem cells (MSCs) with potent anti-inflammatory, regenerative, and immune-modulatory properties are considered a candidate to prevent DGF and acute rejection in renal transplantation. Thus, this prospective multicenter paired study aimed to assess the clinical value of allogeneic MSCs as induction therapy to prevent both DGF and acute rejection in deceased donor renal transplantation.MethodsForty-two renal allograft recipients were recruited and divided into trial and control groups. The trial group (21 cases) received 2 × 106/kg human umbilical-cord-derived MSCs (UC-MSCs) via the peripheral vein before renal transplantation, and 5 × 106 cells via the renal artery during the surgical procedure. All recipients received standard induction therapy. Incidences of DGF and biopsy-proven acute rejection were recorded postoperatively and severe postoperative complications were assessed. Graft and recipient survivals were also evaluated.ResultsTreatment with UC-MSCs achieved comparable graft and recipient survivals with non-MSC treatment (P = 0.97 and 0.15, respectively). No increase in postoperative complications, including DGF and acute rejection, were observed (incidence of DGF: 9.5% in the MSC group versus 33.3% in the non-MSC group, P = 0.13; Incidence of acute rejection: 14.3% versus 4.8%, P = 0.61). Equal postoperative estimated glomerular filtration rates were found between the two groups (P = 0.88). All patients tolerated the MSCs infusion without adverse clinical effects. Additionally, a multiprobe fluorescence in situ hybridization assay revealed that UC-MSCs administered via the renal artery were absent from the recipient’s biopsy sample.ConclusionsUmbilical-cord-derived MSCs can be used as clinically feasible and safe induction therapy. Adequate timing and frequency of UC-MSCs administration may have a significant effect on graft and recipient outcomes.Trial registrationNCT02490020. Registered on June 29 2015

Role of Adipose-Derived Mesenchymal Stem Cells in Full Thickness Wound Healing

Background: Wound healing problems can arise in donor wounds after harvesting a full-thickness graft. Returning Mesenchymal Stem Cells (MSCs) on the wounds may accelerate wound healing. The aim of this study is to analyse the effect of MSCs in the epithelialization process and collagen density on full-thickness wound healing. Methods: The pilot study included 10 patients undergoing excision of a full-thickness skin graft on the groin. Patients were randomly divided into two groups: Mesenchymal Stem Cells (MSCs) and Non-Mesenchymal Stem Cells (Non-MSCs). The MSCs group had previously undergone fat harvesting which was processed into mesenchymal stem cells. Biopsies were taken from both groups on days 14 (proliferative phase) and 45 (maturation phase), and were compared with normal skin (NS; n=5). Epithelial layers of the epidermis were assessed with hematoxylin eosin staining. Collagen density was evaluated with MT staining, and analysed using a light microscope. Result: In the MSCs group and the Non-MSCs group, the number of epithelial layers were significantly higher compared to the NS-group on day 45 (14.7 ± 0.70 and 8.24 ± 0.76 vs 5.43 ± 0.60 respectively; p<0.001 and p<0.001). The collagen density in the MSCs group on day 14 was 33.3 ± 2.46% in the MSCs group and 45.7 ± 5.84% in the non-MSCs group, compared to 54.3 ± 3.71% in the NS-group (p<0.001 and p=0.012 resp.). These values increased on day 45 to 49.2 ± 3.28% in the MSCs group, and 73.4 ± 1.63% in the non-MSCs group. Conclusion: Mesenchymal stem cells increased the number of epithelial layers in the full-thickness wound healing process compared to normal skin. A higher increase was seen in the MSCs-group. On day 45, an increase in collagen density was observed in the MSCs group and Non-MSCs group. Adipose-derived mesenchymal stem cells can be used in the process of full-thickness wound healing. Future randomized controlled trials are needed to confirm these findings.

Phase II Multicenter, Randomized, Double-Blind Controlled Study of Efficacy and Safety of Umbilical Cord–Derived Mesenchymal Stromal Cells in the Prophylaxis of Chronic Graft-Versus-Host Disease After HLA-Haploidentical Stem-Cell Transplantation

Although mesenchymal stromal cells (MSCs) possess immunomodulatory properties and exhibit promising efficacy against chronic graft-versus-host disease (cGVHD), little is known about the efficacy of MSCs in the prophylaxis of cGVHD after HLA-haploidentical hematopoietic stem-cell transplantation (HLA-haplo HSCT). In this multicenter, double-blind, randomized controlled trial, we investigated the incidence and severity of cGVHD among patients, and the changes in T, B, and natural killer (NK) cells after the repeated infusion of MSCs. The 2-year cumulative incidence of cGVHD in the MSCs group was 27.4% (95% CI, 16.2% to 38.6%), compared with 49.0% (95% CI, 36.5% to 61.5%) in the non-MSCs control group (P = .021). Seven patients in the non-MSCs control group had severe lung cGVHD, but no patients in the MSCs group developed typical lung cGVHD (P = .047). After the MSC infusions, increasing memory B lymphocytes and regulatory T cells, as well as the ratio of type 1 T helper to type 2 T helper cells, were observed, whereas the number of NK cells decreased. Our findings suggest that the repeated infusion of MSCs might inhibit cGVHD symptoms in patients after HLA-haplo HSCT, accompanied by changes in the numbers and subtypes of T, B, and NK cells, leading to the acquisition of immune tolerance.

Mesenchymal Stem Cell As a Salvage Treatment for Patients with Refractory Bronchiolitis Obliterans Syndrome after Allogenetic Hematopoietic Stem Cell Transplantation

Background Bronchiolitis obliterans syndrome (BOS) is the most detrimental late pulmonary complications after allogeneic hematopoietic stem cell transplantation, as it is characterized by non-responsiveness to treatment, leading to high morbidity and mortality. Mesenchymal stem cell (MSC) has been considered as an effective treatment for refractory aGVHD, but the response to treat cGVHD, especially refractory BOS, is rarely reported. This study evaluated the efficacy of MSC from bone marrow (BM) of a third-party donor to BOS patients.Methods Fifty-three patients with refractory BOS were enrolled in our prospective study, including 29 patients in MSC group and 24 patients in non-MSC group. All patients had previously failed to at least 2 lines of immunosuppressive therapy. MSCs were given at a median dose of 1×106 cells/kg once weekly for 4 weeks as one cycle treatment. The responsiveness of MSC was evaluated after one cycle, non-responsive patients discontinued MSC treatments, others continued to accept another cycle of MSC treatments.Results Fifty-three patients developed BOS at a median time of 172 days (range, 94 to 398). After a total of 169 doses of MSC were administered, with a median of 6 (range:3-11) doses per patient, the overall response (OR) rate in MSC group was 75.9%, including CR in 13.8% and partial response (PR) in 62.1%. Compared with MSC group, OR rate in non-MSC group was 16.7%, including CR in 4.2% and PR in 12.5% (P=0.000; P=0.233; P=0.000, respectively). Furthermore, the efficacy of MSC to refractory BOS was significantly related with the severity of pulmonary function (mild VS severity, P=0.039). During the median follow-up time of 814 (range:228-2499) days post-transplantation, 7 patients were dead in MSC group, while 18 patients died in non-MSC group. The 5-year OS post-transplantation in MSC group were 68.6%±5.7%, compared with 21.2%±7.1% in non-MSC group (P=0.033). No patients experienced any toxic side effects and other secondary tumors after MSC treatment.Conclusion MSC derived from BM of third-party donors is a promising treatment for patients with refractory BOS. DisclosuresNo relevant conflicts of interest to declare.

Mesenchymal Stem Cells Ameliorate Thymic Functions in aGVHD Patients after Allogenetic Haematopoietic Stem Cell Transplantation

Background Mesenchymal stem cells (MSCs) have been considered as a promising strategy for the prevention and treatment of graft-versus-host disease (aGVHD), but the mechanism of MSCs ameliorating GVHD is still not fully understood. In mice aGVHD model, some studies proposed that MSCs ameliorated GVHD via enhancements in proliferation and function of thymic epithelial cells, but it is not performed in patients.Methods Twenty-five refractory aGVHD patients were enrolled in this study, including 13 patients receiving MSCs treatment and 12 without MSCs treatment as the control group. MSCs derived from bone marrow (BM) of a third-party donor and given at a median dose of 1×106 cells/kg once weekly until aGVHD got complete response (CR) or MSCs were infused for a total of 8 doses. CD4+CD25+Foxp3+ regulatory T cells (Tregs) in peripheral blood were analyzed by flow cytometry and signal joint T-cell receptor excision circle (sjTREC) was monitored by real-time polymerase chain reaction (PCR) before and 4, 8, 12, 16, 24 and 36 weeks after treatments.Results In MSCs group,the overall response (OR) rate for aGVHD was 76.9%, including complete response (CR) in 53.8% and partial response (PR) in 23.1%, while the OR rate in non-MSCs group was 33.3%, including CR in 25% and PR in 8.3%. The OR rate in MSC group is significantly higher than those in the control group (P=0.028). No evident difference of CD4+CD25+Foxp3+Tregs and sjTREC were shown between the patients in MSCs and the control groups before the study treatment (P=0.762, P=0.870). In the evaluated patients, the level of sjTREC in MSCs group is significantly higher at 8, 16, 24 weeks than the control group after treatments (P=0.043, P=0.0301 and P=0.039, respectively.). The level of sjTREC significantly increased at 8 weeks after MSCs treatment, compared with pre-MSCs treatment (P=0.034), and sustained to 36 weeks after MSCs treatment. In the control group, sjTREC increased, but did not change significantly before and after treatments (P>0.05). The level of sjTREC in CR patients is significantly higher than non-response patients at 8, 12, 16, and 24 weeks after MSCs treatment, and sjTREC levels correlated with the response of MSCs treatment (r=0.782). With respect to CD4+CD25+Foxp3+Tregs, they were significantly higher in MSC group at 8, 12 weeks after treatment than the control group (P=0.026 and P=0.029). In MSCs group, the proportion of CD4+CD25+Foxp3+Tregs showed a significant increase at 8 weeks compared with pre-MSCs treatment (P=0.012), and sustained to 36 weeks after MSCs treatment. In the control group, CD4+CD25+Foxp3+Tregs did not significantly change before and after treatment.Conclusions MSCs derived from BM of a third-party donor are effective to refractory aGVHD. MSCs ameliorated aGVHD via repairing thymus, including the enhancements of thymic output function and inducing the generation of Tregs. DisclosuresWu:It was supported by National Natural Science Foundation of China (81270647, 81300445, 81200388); National High Technology Research and Development Program of China (863 Program) (2011AA020105): Research Funding; It was supported by the Technology Plan of Guangdong Province of China (2012B031800403); the project of the Zhujiang Science & Technology Star of Guangzhou city (2013027).: Research Funding. Liu:It was supported by National Natural Science Foundation of China (81270647, 81300445, 81200388); National High Technology Research and Development Program of China (863 Program) (2011AA020105); National Public Health Grand Research Foundation (201202017);: Research Funding; It was supported by Natural Science Foundation of Guangdong Province (S2012010009299); the project of health collaborative innovation of Guangzhou city (201400000003-4, 201400000003-1);: Research Funding; It was supported by the Technology Plan of Guangdong Province of China (2012B031800403); the project of the Zhujiang Science & Technology Star of Guangzhou city (2013027).: Research Funding.

Immunomodulation Effects of Mesenchymal Stromal Cells on Acute Graft-versus-Host Disease after Hematopoietic Stem Cell Transplantation

Refractory acute graft-versus-host disease (aGVHD) is a major cause of death after allogeneic hematopoietic stem cell transplantation. This study evaluated the immunomodulation effects of mesenchymal stromal cells (MSCs) from bone marrow of a third-party donor for refractory aGVHD. Forty-seven patients with refractory aGVHD were enrolled: 28 patients receiving MSC and 19 patients without MSC treatment. MSCs were given at a median dose of 1 × 106 cells/kg weekly until patients got complete response or received 8 doses of MSCs. After 125 doses of MSCs were administered, with a median of 4 doses (range, 2 to 8) per patient, overall response rate was 75% in the MSC group compared with 42.1% in the non-MSC group (P = .023). The incidence of cytomegalovirus, Epstein-Barr virus infections, and tumor relapse was not different between the 2 groups during aGVHD treatment and follow-up. The incidence and severity of chronic GVHD in the MSC group were lower than those in the non-MSC group (P = .045 and P = .005). The ratio of CD3+CD4+/CD3+CD8+ T cells, the frequencies of CD4+CD25+Foxp3+ regulatory T cells (Tregs), and the levels of signal joint T cell–receptor excision DNA circles (sjTRECs) after MSCs treatment were higher than those pretreatment. MSC-treated patients exhibited higher Tregs frequencies and sjTRECs levels than those in the non-MSC group at 8 and 12 weeks after treatment. MSCs derived from bone marrow of a third-party donor are effective to refractory aGVHD. It might reduce the incidence and severity of chronic GVHD in aGVHD patients by improving thymic function and induction of Tregs but not increase the risks of infections and tumor relapse.

Immunologic Effects Of Mesenchymal Stem Cells In The Treatment Of Refractory Acute Graft-Versus-Host Disease

BackgroundMesenchymal stem cells (MSCs) have been considered as a promising strategy for the prevention and treatment of acute graft-versus-host disease (aGVHD), but the mechanism of MSCs ameliorating GVHD is still not fully understood. A few studies suggested that MSCs ameliorated GVHD via protecting and repairing the function of thymus. MethodsTwenty refractory aGVHD patients receiving MSCs treatment were enrolled in this study, and twenty grade II to IV aGVHD patients treated without MSCs were matched as non-MSCs group. MSCs were given at a median dose of 1×106 cells/kg once weekly until aGVHD got complete response (CR) or MSCs were infused for a total of 8 doses. Lymphocyte subsets of T-cell, B-cell, and NK-cell in peripheral blood were analyzed by flow cytometry before and 30, 60, 90, 180 and 360 days after the MSC infusion in MSC group and the corresponding period in the control group. ResultsA total of the 33 patients who survived more than 30 days after the study treatments were evaluated for the alterations in cellular immune compartment and cGVHD, including 15 cases in MSCs group and 18 in non-MSCs group. In MSCs group, patients had a significantly higher CD4+/CD8+ T-cell ratio at 60, 90 and 180 day after MSCs treatments, which subsequently equalized at 360 day compared with non-MSCs group. The MSC group presented higher percentages of CD4+CD25+ regulatory T cells (Treg) comparing with non-MSCs group, especially at 90 and 180 day, and approached at 360 day. The proportion of CD4+CD45RO+ and CD4+CD45RA+ naïve T-cells in MSC group were also higher than those in non-MSCs group at 60, 90 and 180 day, but not different at 360 day. The proportion of CD19+ and CD16+CD56+ was not detected striking difference between the two groups. Four patients (26.7%) experienced cGVHD in MSCs group, compared with twelve (66.7%) in non-MSCs group (p=0.02). ConclusionsIn conclusion, our data indicate that MSCs might ameliorate aGVHD and induce longer-lasting immune tolerance by altering cellular immune compartments in peripheral blood. The alteration of the cellular immune compartments is associated with the protecting and repairing role of MSCs to thymus. Disclosures:Liu:863 Program (No. 2011AA020105): Research Funding; National Public Health Grand Research Foundation (Grant No. 201202017): Research Funding; National Natural Science Foundation of China (Grant No.81000231, No.81270647): Research Funding; Science and Technology Program of Guangzhou of China (11A72121174) : Research Funding.

Mesenchymal Stem Cell As a Salvage Treatment For Refractory Acute Graft-Versus-Host Disease: a Matched Pair Analysis

BackgroundRefractory acute graft versus host disease (aGVHD) is a major cause of death after allogenetic haematopoietic stem cell transplantation (allo-HSCT). This study evaluated the efficacy and safety of mesenchymal stem cells (MSCs) from bone marrow of a third-party donor to refractory aGVHD. MethodsTwenty-five patients with refractory aGVHD were enrolled in this prospective study. MSCs were given at a median dose of 1×106 cells/kg once weekly until aGVHD got complete response (CR) or MSCs were infused for a total of 8 doses. In order to evaluate infections, tumor relapse and cGVHD, 25 refractory aGVHD patients with MSCs treatment was matched with grade II-IV aGVHD patient without MSCs in the corresponding period ResultsAfter a total of 112 doses of MSCs were administered, with a median of 4 (range:2-12) doses per patient, the overall response (OR) rate for aGVHD was 72%,including CR in 56% and partial response (PR) in 16%. The efficacy of MSCs to aGVHD was significantly related with the severity and the number of involved organs of aGVHD, but unrelated with the onset timing of MSC. The incidence of CMV and EBV infections, including viremia and associated disease, was not different between MSCs and non-MSCs groups during aGVHD treatment and follow-up. At a median follow-up time of 126 (range: 49–1067) days post-transplantation, only two patients relapsed in MSCs group, compared with four relapsed in the control group. Tumor relapse was not different between the two groups (P=0.771). No toxic side effects and other secondary tumors were observed after MSCs treatment except for one EBV-associated post-transplant lymphoproliferative disorders (PTLD). The incidence of cGVHD in MSCs group, especially extensive cGVHD, was lower than that in non-MSCs group (25.0% Vs 68%, P=0.001; 20.0% Vs 64%, P=0.043, respectively). The ratio of CD3+CD4+/CD3+CD8+ T cells and the proportion of CD4+CD25+ regulatory T cells (Tregs) at 8 weeks after MSCs were higher than that before treatment (P=0.037 and P=0.020, respectively), and there were not different from the healthy people at 36 weeks after treatment. ConclusionsMSCs derived from bone marrow of third-party donors are effective to refractory aGVHD. It might not increase the risks of infections, tumor relapse, but reduce the incidence and severity of cGVHD. Disclosures:Liu:Science and Technology Program of Guangzhou of China (11A72121174): Research Funding; National Natural Science Foundation of China (Grant No.81000231, No.81270647): Research Funding; National Public Health Grand Research Foundation (Grant No. 201202017): Research Funding; 863 Program (No. 2011AA020105): Research Funding.

Isogenic mesenchymal stem cells transplantation improves a rat model of chronic aristolochic acid nephropathy via upregulation of hepatic growth factor and downregulation of transforming growth factor β1

Chronic aristolochic acid (AA) nephropathy (CAAN) caused by intake of AA-containing herbs is difficult to treat. We evaluated the therapeutic effect of bone marrow (BM) mesenchymal stem cells (MSCs) on a rat model of CAAN. Female Wistar rats were fed with decoction of Caulis Aristolochia manshuriensis by intragastric administration. MSCs were prepared from BM of male Wistar rats and injected into female CAAN rats through tail vein. Body weight, renal function, and urinary excretion of these CAAN rats were monitored before killing at the end of the 20th week. Blood, urine, and tissue samples were collected from experimental (MSC and non-MSC) and normal control groups. All animals developed renal fibrosis after 12 weeks of intake of AA-containing decoction. Fibrosis in the MSC groups was significantly reduced as examined with light and electron microscopy. Blood urea nitrogen, serum creatinine, and urine protein levels were significantly reduced and hemoglobin levels were improved in the MSC group as compared with the non-MSC group (p < 0.01). The expression of TGF-β1 mRNA and protein was reduced but hepatic growth factor (HGF) was increased in the MSC group compared with the non-MSC group, but still higher than the normal control level as measured by immunochemical, RT-PCR, and western blotting assays (p < 0.01). The renal fibrosis of CAAN could be protected by isogenic MSC transplantation, probably via upregulation of HGF and downregulation of TGF-β1.

The correlation between cotransplantation of mesenchymal stem cells and higher recurrence rate in hematologic malignancy patients: outcome of a pilot clinical study

In this open-label randomized clinical trial, HLA-identical sibling-matched hematopoietic stem cells (HSC) were transplanted (non-MSCs group, n=15) or cotransplanted with mesenchymal stem cells (MSCs) (MSCs group, n=10) in hematologic malignancy patients. The median number of MSCs infused was 3.4 x 10(5) kg(-1) (range, 0.3-15.3 x 10(5) kg(-1)). MSCs infusions were well tolerated. The median time to neutrophil engraftment (absolute neutrophil count >0.5 x 10(9) l(-1)) was 16 days for MSCs group and 15 days for non-MSCs group. The median time to platelet engraftment (platelet count >50 x 10(9) l(-1)) was 30 and 27 days, respectively. Grades II-IV acute graft-versus-host disease (GVHD) was observed respectively, in one (11.1%) and eight (53.3%) evaluable patients. Chronic GVHD was found in one (14.3%) and four (28.6%) evaluable patients. The number of patients who relapsed were six (60.0%) and three (20.0%), and the 3-year disease-free survivals were 30.0 and 66.7%, respectively. Thus cotransplantation of MSCs and HSCs may prevent GVHD, but the relapse rate is obviously higher than the control group. We conclude that use of MSCs must be handled with extreme caution before a large-scale clinical trial is performed.

Effect of human placenta derived mesenchymal stem cells on cord blood lymphocyte transformation

To study the effect of human placenta derived mesenchymal stem cells (MSCs) on the immune function of lymphocytes derived from human umbilical cord blood. Mononucleated cells (MNC) were isolated from human placenta tissue perfusate by density gradient fractionation. Individual colonies were selected and cultured. The culture-expanded cells were characterized by immune phenotyping so as to identify the MSCs. The MSCs were cultured under conditions promoting differentiation to osteoblasts or adipocytes. MNCs were isolated from adult peripheral blood and human umbilical cord blood and cultured, then the adherent cells were excluded and the suspended cells, lymphocytes, were inoculated in the culture fluids of MSCs of different concentrations and phytohemagglutinin (PHA), a nonspecific mitogenic stimulant, was added for 84 hours (MSC + PHA groups), then (3)H-thymidine deoxyribose ((3)H-TdR) was added for 12 hours. The cells were collected and scintillation counter was used to calculate the counts per minute (cpm). Pure lymphocytes without MSC and stimulated by PHA were used as control group (non-MSC Group) and pure lymphocytes and pure MSCs without PHA were used as blank control groups (non-PHA Group). From human placenta MSCs were successfully isolated and exhibited fibroblast-like morphology. Flow cytometric analysis showed that the placental MSCs were a homogeneous cell population devoid of hematopoietic cells positive for CD29, CD44, CD73, CD105, CD166, and HLA-ABC positive and negative for CD34, CD45, and HLA-DR. They could be induced into adipocytes or osteocytes. The cpm value of the non-MSC Group was 171 855 +/- 31 454, significantly higher than that of non-PHA Group (26 453 +/- 5268). The cpm values of the different concentrations MSC + PHA groups were all significantly lower than that of non-MSC Group in a dose-dependent manner; when the dose of MSCs was 2 x 10(5) the suppression rate was 79.97% in PB and 64.06% in UCB. MSCs derived from postpartum human placenta, an important and novel source of multipotent stem cells, suppress blood lymphocyte proliferation, thus may be used to reduce graft -versus-host disease (GVHD) in recipients.