Allogeneic Stem Cell Research Articles

Experience of stem cell use in treatment of skin burns

The results of three-year research on the use of allogeneic mesenchymal stem cells of adipose tissue (AMSCs) in the treatment of skin burns of II-III degree are presented. in a complex with wounds dressing of nanofibers chitosan and copolyamide, hyaluronic acid. It was found that with surgical necrectomy, introduction of AMSCs and substitution of defects with natural polymer coatings, the healing time is reduced by 89% (p < 0.05). Isolated administration of MSC reduces the healing period by no more than 5% (p > 0.05). The combined use of wounds dressings of nanofibers chitosan and copo lyamide with MSC accelerates the regeneration process by 26% (p < 0.05), with the introduction of AMSCs accelerating the development of granulation tissue by the fifth day of observation by 83% (p < 0.01). Joint use of wound coverings on the basis of hyaluronic acid with AMSCs is accompanied by an increase in the number of vessels of the microcirculatory bed in the defect area by 185% (p < 0.01). Clinical evaluation of the effectiveness of drugs with stem cells – a gel for topical application and a suspension of MSC LC for injection administration demonstrate their ability to optimize regeneration in the burn zone. Application of gel with AMSCs reduces the duration of epithelialization of border (dermal) burns by 2.2-2.4 times, with the final healing period being reduced by 59% (p < 0.01) and the suppuration frequency by 30% (p < 0.05). The introduction of a suspension of AMSCs into the zone of deep burn increases the frequency of engraftment of autografts, stimulates angiogenesis and proliferation of fibroblasts in the superficial and deep layers of the dermis. In the area of MSC administration, the LC perfusion level and the amplitude of blood flow fluctuation are twice as high as the values in the zones without the introduction of cells.

Immunological effects of the intraparenchymal administration of allogeneic and autologous adipose-derived mesenchymal stem cells after the acute phase of middle cerebral artery occlusion in rats

BackgroundAdipose-derived mesenchymal stem cell (ADMSC) therapy can promote recovery from cerebral ischemia; however, more information regarding appropriate sources of ADMSCs is required. This study was aimed at analyzing the immunogenicity of rat ADMSCs by comparing the immunological effects of intraparenchymal administration of allogeneic ADMSCs (allo-ADMSCs) and autologous ADMSCs (auto-ADMSCs) after the acute phase of middle cerebral artery occlusion (MCAO) in rats.MethodsAllo- or auto-ADMSCs from rats (1 × 106 cells) were transplanted into Lewis rats 8 days post MCAO. The immunogenicity of ADMSCs was analyzed using coculture with T lymphocytes. The in vivo immune response induced by rat ADMSCs and the viability, migration, and differentiation of transplanted ADMSCs were detected using immunohistochemistry. Apoptosis within the populations of transplanted cells were detected using a TUNEL assay. Infarct volume was detected by 2,3,5-triphenyltetrazolium chloride staining. Post-treatment neurological function was evaluated using a modified neurological severity score and rotarod test. Data were analyzed using Kruskal–Wallis and Mann–Whitney U tests.ResultsCompared with allo-ADMSCs, auto-ADMSCs showed lower immunogenicity and evoked weaker immunological responses. Allo-ADMSCs evoked significantly stronger protein expression of interleukin-2 and interferon-gamma, as well as the local accumulation of CD4+ T lymphocytes, CD8+ T lymphocytes, and microglial cells. This indicates that auto-ADMSCs may contribute to higher survival rates, longer survival time, wider migratory scope, and fewer apoptotic cells. In addition, a small number of transplanted auto-ADMSCs expressed astrocyte-like and neuron-like markers 28 days after transplantation. We did not observe surviving transplanted allo-ADMSCs at this time point. We also found that auto-ADMSCs induced a greater degree of functional recovery and a greater reduction in infarct volume than allo-ADMSCs 28 days after transplantation.ConclusionsAuto-ADMSCs were more effective than allo-ADMSCs in promoting recovery and reducing the infarct volume of MCAO rats. This could be associated with better viability, migratory ability, and differentiation potential, as well as a lower rate of apoptosis. Confirmation of the superiority of auto-ADMSCs and clarification of the underlying mechanisms will provide a theoretical basis for the improved clinical treatment of cerebral infarction.

Focused Regulatory T Cell Repertoires Are Indicative of Successful GvHD Control in Experimental and Clinical Stem Cell Transplantation

Acute Graft versus Host Disease (aGvHD) remains a major complication and leading cause of mortality after allogeneic stem cell or bone marrow transplantation (BMT). Current strategies for treatment are still based on unspecific immunosuppressive therapy. Over the last decade, there have been major advances in the field of adoptive immunotherapy using regulatory CD4+CD25+Foxp3+ T cells (Treg cells). Nonetheless, not much is known about the exact mechanisms of Treg-mediated suppression, and even less about the importance of T cell receptor (TCR) specificity and its diversity on the functionality of Tregs.We hypothesized that an optimal Treg TCR repertoire is necessary for successful prevention of aGvHD. To test this hypothesis, we sequenced the TCR repertoire of 8 patients who were diagnosed with aGvHD on day 30 post transplantation and compared it with the TCR repertoire of nine GvHD-free patients. Analysis of GvHD-free patients on day 30 (and 100 days-follow up) revealed a lower TCR diversity when compared to the patients suffering from GvHD. A more detailed analysis of the TCR repertoire showed that in patients without GvHD, fewer clonotypes were needed to comprise 50% of the whole repertoire as compared with samples from patients with GvHD (Figure 1A). Thus, expansion of protective clones indicates their potent immunosuppressive capabilities.Next, we employed a well-described murine model of allogeneic BMT (BL/6–>Balb/c) with co-injection of Tregs. Recipient Balb/c mice transplanted in this fashion were previously shown to be protected from aGvHD. However, the mechanisms involved in this Treg-mediated protection are not fully understood. Therefore, Tregs were FACS sorted from B6.Cg-Foxp3tm1Mal/J mice based on their Foxp3 expression. Recipient mice were transplanted with T-cell depleted bone marrow and a mixture of conventional T cells (Tconv) and Tregs in 1:1 ratio. Transferred Tregs were re-sorted on day 7 and day 14 from secondary lymphoid organs based on the congenic marker Thy 1.1 and Foxp3 expression. Using this model, we investigated the kinetics of the Treg TCR repertoire early after BMT in 5 independent experiments. We found a consistently similar narrowing of the repertoire and clonal expansion in mice protected from GvHD (Figure 1B). Diversity analysis using inverse Simpson Index also confirmed our findings. These data further support the notion that a clonal expansion of Tregs is necessary for an optimal immunosuppression of an allogeneic response, both in human and in mice. To test the functionality and phenotype of such expanded Tregs, they were re-sorted from BMT-recipient mice 14 days after transplantation. These Tregs were expanded using α-CD3 and α-CD28 antibodies and were functionality tested in an in vitro Treg suppression assay. Re-sorted Tregs after expansion showed expression of established Treg surface and intracellular markers such as Helios, CD25, GITR and CTLA-4. For the suppression assay, responder CD4 Tconv were stained with a proliferation tracking dye eFluor670 and stimulated in vitro with CD3 and CD28 beads in the presence of different ratios of re-sorted and expanded, or polyclonaly activated Tregs as the control. Allo-specific ex vivo Tregs exhibited a superior suppressive potential when compared with polyclonaly activated Tregs in vitro.Taken together, our current study highlights the importance of specific Treg driven allo-response in GvHD prevention. Further studies are needed, particularly in larger patient cohorts to confirm these findings. However, we propose that this approach might lead to identification and subsequent use of specific Treg clones with high immunosuppressive capacity for the prevention of aGvHD. [Display omitted] DisclosuresGanser:Novartis: Membership on an entity's Board of Directors or advisory committees. Koenecke:abbvie: Consultancy; BMS: Consultancy; Roche: Consultancy; Amgen: Consultancy.

Low Dose of Human scFv-Derived BCMA-Targeted CAR-T Cells Achieved Fast Response and High Complete Remission in Patients with Relapsed/Refractory Multiple Myeloma

▪Introduction: B Cell Mature Antigen (BCMA)-targeted chimeric antigen receptor T (CAR-T) cell therapy emerges as promising treatment for patients with relapse/refractory multiple myeloma (RRMM). Previous studies indicate patients who receive high-dose CAR-T cells may achieve better remission but have worse adverse events, like cytokine release syndrome (CRS). To solve this dilemma, we have developed novel autologous CAR-T therapeutics CT053 that are genetically modified T cells comprising an extracellular anti-BCMA human scFv and an intracellular 4-1BB costimulatory motif connected to a CD3-zeta T cell activation domain.Methods: A multi-center investigator-initiated clinical study is designed to evaluate CT053 in patients with RRMM who have failed in the prior treatment with ≥2 regimens, including a proteasome inhibitor, an immunomodulatory agent, and anti-CD38 monoclonal antibody. All patients have ≥50% BCMA expression on malignant cells. Patients are subjected to the lymphodepletion with 20-25 mg/m2 fludarabine and 300-500 mg/m2 cyclophosphamide daily for 2-4 days prior to receiving single-dose infusion of CT053 CAR-T cells. In case of progressive disease, patient may be dosed again on basis of investigators' evaluation of the disease status, BCMA expression and CAR-T persistence. Most enrolled patients received a single dose of 1.5 x 108 cells, except for 1 patient who received 0.5 x 108 cells and 1 patient who was infused with 1.8 x 108 cells. The primary outcome measure is incidence of adverse events (AEs), including dose-limiting toxicities (DLTs) and CAR T related AEs. Additional outcome measures include clinical response assessed according to the IMWG Uniform Response Criteria for Multiple Myeloma, overall and progression-free survival, pharmacokinetics and pharmacodynamic of CT053.Results: The study was performed in compliance with the declaration of Helsinki. As of the data cut-off date (July 10th, 2018), 16 patients (median 55 [39 to 67] years old) with a median of 3.9 (0.4 to 16.7) years since MM diagnosis, were infused with CT053. Patients had a median of 4 prior different regimens (range 2 to 10), and 56% (9/16) patients received prior autologous or allogeneic stem cell transplant.Among 16 patients, no neurotoxicity and no dose-limiting toxicities (DLT) were observed. The most common grade≥3 CAR-T related AEs were 3 thrombocytopenia (19%), 3 leukopenia (19%), 2 anemia (13%), 2 neutropenia (13%), 2 fever (13%) (Figure 1A). CRS was reported in 3 patients, including 1 Grade 3, 1 Grade 2 and 1 Grade 1, who had rapid recovery after Tocilizumab administration.13/16 patients were eligible for initial evaluation of early clinical response with a median observation period of 8 (4 to 36) weeks. Overall response rate (ORR) in 13/13 patients was 100% post treatment. 12/13 patients (92%) quickly achieved partial response (4 PR), very good PR (6 VGPR), and complete response (2 CR) within 4 weeks post single-dose infusion (Figure 1B). 5/12 patients (42%) who were dosed at ≥1.5 x 108 CT053 CAR-T cells obtained CR at a median of 8 weeks post treatment. Durable responses from 4 weeks towards the data cut-off date were found in 12/13 patients (92%). One relapse from VGPR by the Week 12 was reported in a patient who had aggressive RRMM at enrollment and received the reduced dose of lymphodepletion regimen at 19 mg/m2 fludarabine and 192 mg/m2 cyclophosphamide for 2 days prior to CT053 infusion. Because positive BCMA expression on malignant cells was verified at relapse, the patient was re-dosed with CT053 at the Week 16 and subjected to the further evaluation.All patients had detectable CAR-T expansion from Day 3 post CT053 infusion. Expansion peaks were found on Day 7 (5/13), Day 14 (6/13) and Day 21 (2/13). 11/13 patients had notable persistence of CT053 CAR-T cells up to 4-6 months. The only relapsed patient had the lowest CAR-T expansion peak among 13 patients, indicating the potential correlation between CAR-T expansion and response outcome.Conclusions: Data from this early-stage clinical study showed the unparalleled safety and efficacy of CT053 CAR-T cells. Major AEs were transient, manageable, and reversible. 100% ORR in 13/13 evaluable patients were reported post single-dose infusion of 0.5~1.8 x 108 cells. 5/12 patients who were dosed at ≥1.5 x 108 CAR-T cells rapidly achieved durable CR at median of 8 weeks, suggesting CT053 could be developed as competitive therapeutics to treat patients with RRMM. DisclosuresRuan:CARsgen Therapeutics: Employment. Xiao:CARsgen Therapeutics: Employment, Equity Ownership. Wang:CARsgen Therapeutics: Employment, Equity Ownership. Li:CARsgen Therapeutics: Employment, Equity Ownership.

Risk of Post-Transplant Lymphoproliferative Disorders (PTLD) in Solid Organ Transplantation Patients with EBV Viremia

Introduction Post-transplant lymphoproliferative disorders (PTLD) are mostly Epstein-Barr virus (EBV) positive lymphoid proliferations resulting from immunosuppression following allogeneic stem cell or solid organ transplantation (SOT). Despite this strong association, there is a lack of data evaluating the risk of PTLD in SOT patients (pts) with (w/) EBV viremia. The significance of EBV detection remains unclear and can lead to unwarranted preemptive treatments in SOT pts. The aim of this study is to assess the association between peripheral blood EBV viral load and risk of PTLD post SOT. Methods We identified 6468 adult and pediatric pts from the Cleveland Clinic SOT database who underwent SOT from 2002-2016. We included pts who had ≥1 EBV viral load test by PCR, and excluded pts w/ first EBV test at or after PTLD diagnosis. EBV viral load was quantified by polymerase chain reaction (PCR) of whole blood samples and expressed as log copies/mL. Lower detection limits varied from 2.00 to 2.70 log copies/mL. EBV monitoring post SOT was done at the physician9s discretion. Potential risk factors for PTLD were assessed using Fine and Gray competing risk regression. Stepwise analysis was used to identify multivariable risk factors. Landmark analyses at 2 and 6 months post SOT (LM-2 and LM-6) were performed based on pts9 peak pre-landmark EBV levels. Pts were excluded if they died, lost follow-up (f/u) or developed PTLD prior to the landmark. Two multivariable models were assessed at each landmark using EBV level cutoffs of 3.00 and 4.00 log. Results Of 6324 pts w/ available f/u data, 3348 (52%) had ≥1 quantitative EBV PCR test and were included in this analysis w/ a total of 91,067 tests performed. Median age at SOT was 54 years (range 0.3-79) and 63% were male. The most common SOT was kidney (38%) followed by lung (37%), liver (18%), heart (7%), pancreas (6%) and intestine (2%), w/ 7% receiving >1 organ type (Table 1). Of 3348 pts included, 1503 (45%) developed EBV viremia and 68 (2%) developed PTLD; 45/1503 (3.0%) and 23/1845 (1.2%) of pts w/ and without (w/o) EBV viremia, respectively. EBV was detected in 44% of pts w/o PTLD and 66% of pts w/ PTLD. Median age at PTLD diagnosis was 58 years (range 1-75), with a median time from SOT to PTLD of 33 months (range 2-146). PTLD morphology was DLBCL (n=39), polymorphic (n=9) Burkitt (n=5), other (n=10) and unknown (n=5). EBV-encoded RNA (EBER) testing in tumor was positive in 47%, negative in 44% and unknown in 9% of cases. In pts w/ and w/o PTLD, tacrolimus was the most common immunosuppressant used at 1 month (99% and 89%), 1 year (94% and 88%) and 2 years (81% and 74%) post SOT, respectively. First EBV was checked at a median of 54 days (range 0-5090) in pts w/o PTLD and 28 days (range 0-4308) in pts w/ PTLD. The median number of EBV tests/pt before PTLD or last f/u was 4 (range 1-214) in pts w/o PTLD and 6 (range 1-123) in pts w/ PTLD. Peak EBV levels ≥3.00 and ≥4.00 log were detected in 36% and 13% of pts w/o PTLD, and 60% and 40% of pts w/ PTLD, respectively. Median f/u in both cohorts for pts who were alive was 6.1 years. In multivariable analysis (MVA) for non-EBV risk factors for PTLD, liver (HR 2.19, 95% CI 1.31 - 3.66, p=.003) and intestine SOT (HR 4.62, 95% CI 1.84 - 11.6, p=.001) were the only factors associated w/ higher PTLD risk; age, years since SOT, gender, race, other types of SOT and >1 SOT were not significant. 1685 pts were eligible for LM-2 (43 w/ PTLD) and 2093 for LM-6 (36 w/ PTLD). In univariable analysis at LM-2 and LM-6, peak EBV levels ≥4.00 log (LM-2: HR 2.72, p=.016; LM-6: HR 7.08, p Conclusion In this large cohort of SOT pts, Disclosures Hill:Pharmacyclics: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Genentech: Honoraria, Membership on an entity9s Board of Directors or advisory committees, Research Funding; Abbvie: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Seattle Genetics: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Amgen: Research Funding; Pharmacyclics: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Seattle Genetics: Honoraria, Membership on an entity9s Board of Directors or advisory committees; Pfizer: Honoraria, Membership on an entity9s Board of Directors or advisory committees.

EARLY Post-Transplant Events , Cost of Admission and Mortality, in Patients Undergoing Allogeneic Transplants from Identical Siblings, Unrelated Donors or Haploidentical Donors

Abstract Background. The outcome of allogeneic hemopoietic stem cell transplantation (HSCT) is measured in terms of graft versus host disease (GvHD), non-relapse mortality (NRM) and survival. Days of Hospital stay and number of re-admissions, are important surrogates of outcome, quality of life, and also of costs, but are usually not reported. Aim of the study . Assess the number of days alive and outside the Hospital (DAOH) , together with the frequency of a new re-admission, in the first 100 days after transplant. Patients. We analyzed 212 patients who received an allogeneic HSCT from matched sibling (SIB) (n=64), unrelated donors (UD) (n=74) and family haploidentical donors (HAPLO) (n=74). Median age was 49 years (19-71), disease phase was in remission in 53%; diagnoses was acute leukemia (66%) , MDS (14%) chronic disorders 20%. DAOH. The median DAOH for SIB, HAPLO and UD grafts was 78, 72 and 66 days (p=0.0001). The median DAOH for SIB patients was significantly longer than for UD patients (p=0.00002) and for HAPLO grafts (p=0.0008); the median DAOH for UD and HAPLO patients were comparable (p=0.4). Donor type was the strongest predictor of DAOH , followed by a Sorror score >2 (p=0.04). Re-admission. Fifty four patients, of 185 discharged, required a re-admission for complications. the first cause for readmission was fever of unknown origin (54%), followed by GvHD (18,5% ) ,cystitis (8%) , relapse (7%) and respiratory problems (7%). The only factor predicting re-admission was advanced disease (p=0.01). Patients who were re-admitted to hospital within 100 days had a significantly higher risk of non relapse mortality (NRM) (25%) as compared to patient non re-admitted (5%) irrespective of the cause for re-admission (p=0.0001). In a multivariate analysis re-admission was the strongest predictor of NRM, with a risk ratio of 10.9 (p=0.0002). Days of admission and cost. The average number of days in hospital within 100 days from transplant, was 37,6 for UD, 35,0 for HAPLO and 25,0 for SIBS (p=0.0002). The average cost of admission within 100 days from HSCT, was €69522 for UD, €64715 for HAPLO and €46225 euros for SIBS. Conclusion. HAPLO transplants with PT-CY and UD transplants , have lower numbers of DAOH, as compared to SIB grafts, which implies longer stay in hospital and greater cost. Re-admission to Hospital within 100 days is predicted by disease phase and has a very strong impact on non relapse mortality. Figure. Figure. Disclosures No relevant conflicts of interest to declare.

USING MESENCHYMAL STEM CELLS FOR TREATING GINGIVAL RECESSION IN THE EXPERIMENT

Aim. This research was conducted to study the type of clinical changes in the diseased periodontal tissues by means of using mesenchymal stem cells for treating gingival recession in the experiment.Materials and methods. Adipose tissue in a volume of 1-2 ml was sampled from one specimen in sterile conditions in order to obtain allogeneic mesenchymal stem cells before the beginning of the experimental studies. Random-bred female white rats (60 specimens) were used as a model in the experiment. The surgical intervention was performed in the area of incisors on the upper and lower jaws of rats. All animals were divided into 5 groups (10 rats in each group) depending on the planned method of the treatment. The control group, intact rats, consisted of 10 laboratory animals with a healthy gingiva. The creation of a model of the experimental gingival recession was carried out by the mechanical V-shaped excision of periodontal tissues.Results. The experimental studies showed the possibility of complete regeneration of the dentogingival papillae as well as periodontal tissues regeneration in the area of the experimental gingival recession during the first 28 days. Meanwhile, there is a complete absence of inflammatory signs in the 5th group (hyperemia, edema, gingival bleeding), along with their significant decrease in the 3rd and the 4th groups that confirms the pronounced therapeutic effect of mesenchymal stem cells and sterile bioplastic collagen material «Collost» (7% gel).The conclusion. While studying the type of clinical changes in diseased periodontal tissues using mesenchymal stem cells in the treatment of gingival recession, we established the positive dynamics in the experiment. The decrease in the intensity and prevalence of gingival inflammation starts from the 14th day. On the 28th day there was noted a complete absence of inflammatory signs in the animals after injecting the transplant consisting of the cell suspension on the sterile bioplastic material Collost (7% gel). Furthermore, the significant increase in the regeneration of the gingival margin was observed on the 24th day from the moment of creating the gingival recession model. The complete regeneration of the dentogingival papillae and the absence of the gingival recession were noted on the 38th day of general observation.

APPLICATION OF CELLULAR TECHNOLOGIES FOR REGENERATION OF PERIODONTAL TISSUES IN EXPERIMENT

A promising scope of modern scientific research is the use of autologous and allogeneic mesenchymal stem cells for regeneration of periodontal tissues. The aim of the study was to evaluate the nature of morphological changes in the pathologically altered periodontal tissues after injection of a biotransplant containing mesenchymal stem cells of the adipose tissue immobilized on a collagen carrier in an animal experiment. In the experiment, 60 randobbred females of white rats were used as a model, whose adipose tissue was taken to obtain allogenic mesenchymal stem cells. All animals were divided into 5 groups, depending on the planned method of treatment – 10 rats each. The control group consisted of 10 laboratory animals with healthy gingiva. The experimental gingival recession model was created by the V-shaped excision of periodontal tissues. The bioplastic collagen material “Collost” gel 7 % in isolated form determines the fibrosis intensification and serves as a “matrix” for the formation of a fibrous tissue, ensures the adhesion of stem cells and their transformation into pro- and fibroblasts. Injection of a cell transplant suspension into physiological saline activates the processes of cell proliferation and transformation of fibroblast differentiating cells. Suspension of the cell transplant on a sterile bioplastic collagen material “Collost” gel 7 % enhances the effects of gel and stem cells, promotes the leveling of atrophic and dystrophic changes in the gum, strengthening a mechanical component, reducing the recession of the gum and the depth of the gingival pocket.

A proof‐of‐concept study assessing the potential of allogeneic chondrogenic induced mesenchymal stem cells as a treatment for osteoarthritis in the horse

A proof‐of‐concept study assessing the potential of allogeneic chondrogenic induced mesenchymal stem cells as a treatment for osteoarthritis in the horse

P5676Safety and immunomodulatory action of epicardial patches combined with allogeneic adipose-derived mesenchymal stem cells in a rodent and porcine model of myocardial infarction

P5676Safety and immunomodulatory action of epicardial patches combined with allogeneic adipose-derived mesenchymal stem cells in a rodent and porcine model of myocardial infarction

Десятилетний опыт применения аллогенной трансплантации гемопоэтических стволовых клеток от гаплоидентичного донора неманипулированного трансплантата у детей и подростков с острыми лейкозами высокой группы риска

Десятилетний опыт применения аллогенной трансплантации гемопоэтических стволовых клеток от гаплоидентичного донора неманипулированного трансплантата у детей и подростков с острыми лейкозами высокой группы риска

Results of program acute myeloid leukemia therapy use in National Medical Research Center for Hematology of the Ministry of Health of Russian Federation.

To analyze treatment results of 172 patients with acute myeloid leukemia (AML) aged 18-60 years in National Medical Research Center for Hematology of MHRF. Inductive and consolidation program for 139 (80%) patients was based on a standardized protocol: 4 courses "7+3" with different anthracycline use (2 courses of daunorubicin, idarubicin, mitoxantrone) and continuous use of cytarabine on the second inductive course. In 20% of patients cytarabine courses at the dose of 1 g/m2 2 times a day for 1-3 days combined with idarubicin and mitoxantrone were used as two consolidation courses. Allogenic bone marrow transplantation was performed in the first complete remission (CR) period in 40% of patients. The frequency of CR achievement in all patients was 78.6%, refractory forms were observed in 13.9% of patients, early mortality - in 7.5% of patients. Seven-year overall survival (OS) rate was 40.7%, relapse free survival (RFS) - 43.2%. When estimating effectiveness depending on cytogenetic risk group it was demonstrated that 5-year OS and RFS in patients with translocation (8; 21) cannot be considered as satisfying, it accounted for 50 and 34%, respectively. At the same time in patients with 16th chromosome inversion (inv16) these characteristics accounted for 68.6 and 63.5%. Acquired results forced reconsidering of the consolidation program in AML patients of this subgroup. The median time to allogenic blood stem cells transplantation (allo-BSCT) in patients with first CR was 6.5 months that was taken as a reference point in landmark analysis of patients in whom allo-BSCT was not performed. Landmark analysis showed that in AML patients of favorable prognosis group allo-BSCT does not significantly reduce the probability of relapse (0 and 36%) and does not influence RFS (33 and 64%). In patients of border-line and poor prognosis allo-BSCT significantly reduces relapse probability (26 and 66%; 20 and 100%) and significantly increases a 7-year RFS (68.7 and 30%; 45.6 and 0%). Allo-BSCT also results in significant RFS increase and reduces the probability of relapse (25 и 78%) in patients in whom CR was achieved only after the second induction course. At the same time allo-BSCT does not influence patients who achieved CR after the first treatment course: 55 and 50%. Multivariate analysis showed that cytogenetic risk group (HR=2.3), time of CR achievement (HR=2.9), and allo-BSCT transplantation (HR=0.16) are independent factors for disease relapse prognosis after achieving CR.

Evaluation of the Efficiency of Allogenic Adipose Tissue Mesenchymal Stem Cells Therapy for Tacrolimus Dose Minimisation in Patients with Acute Kidney Injury after Liver Transplantation

Evaluation of the Efficiency of Allogenic Adipose Tissue Mesenchymal Stem Cells Therapy for Tacrolimus Dose Minimisation in Patients with Acute Kidney Injury after Liver Transplantation

Foscarnet treatment of cytomegalovirus infection in haploidentical or unrelated donor transplants

We studied 97 patients who developed cytomegalovirus (CMV) viremia following an allogeneic hemopoietic stem cell transplant (HSCT) between 2010 and 2015, treated with foscarnet, with the aim of assessing efficacy and safety. The donor was unrelated in 30 patients (UD) and a family HLA-haploidentical donor (HAPLO) in 67 patients: the former (UD) received a prophylaxis for graft-versus-host disease (GvHD), based on antithymocyte globulin (ATG); the latter (HAPLO) received GvHD prophylaxis, based on post-transplant cyclophosphamide (PT-CY). Renal and hematological toxicity were defined according to NCI-CTCAE4 criteria. In univariate analysis, CMV response was 84% in HAPLO vs 59% in UD grafts (p = 0.01) and 90 vs 66% (p = 0.02) for patients with a CMV viral load within or over the median value. In multivariate analysis, the CMV viral load was the strongest predictor of response to foscarnet (p = 0.02), followed by donor type (p = 0.06). Renal impairment developed in 14% of the patients. Overall survival was 69%:, advanced phase at transplant (p = 0.01) and ATG-based regimens (p = 0.02), were the only two predicting factor. In conclusion, CMV response to foscarnet treatment is predicted by a lower CMV load and GvHD prophylaxis. Renal toxicity of foscarnet is not a limiting factor.

Spinal cord stem cell grafts in pigs

Spinal Cord Injury Neuronal precursor cells (NPCs) hold promise for treating spinal cord injury. Testing viability and engraftment properties of NPC transplants in large animal models is essential for understanding the clinical potential of this approach. Strnadel et al. transplanted syngeneic and allogeneic induced pluripotent stem cell–derived NPCs (iPSC-NPCs) into the spinal cords of naive pigs and pigs with spinal cord injury. The transplanted cells showed a good safety profile, long-term survival, and differentiation into mature neurons and glial cells. Successful engraftment of allogeneic iPSC-NPCs required only temporary immunosuppression, an important consideration for the future clinical evaluation of iPSC-NPCs for treating spinal injuries. Sci. Transl. Med. 10 , eaam6651 (2018).

Prediction of acute GVHD and relapse by metabolic biomarkers after allogeneic hematopoietic stem cell transplantation.

There are very few studies investigating metabolic biomarkers to predict acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT). Metabolic models can provide a framework for analyzing the information-rich omics data sets in this setting. Four hundred and fifty-six samples from one hundred and fourteen consecutive patients who underwent HSCT from January 2012 to May 2014 were collected for this study. The changes in serum metabolite levels were investigated using a gas chromatography-mass spectrometry-based metabolomics approach and underwent statistical analysis. Significant metabolic changes were observed on day 7. The stearic acid/palmitic acid (SA/PA) ratio was effective in the diagnosis of grade II-IV aGVHD. Multivariate analysis showed that patients with high SA/PA ratios on day 7 after HSCT were less likely to develop II-IV aGVHD than patients with low SA/PA ratios (odds ratio [OR] = 0.06, 95% CI 0.02-0.18, P < 0.001). After the adjustment for clinical characteristics, the SA/PA ratio had no significant effect on overall survival (hazard ratio [HR] = 1.95, 95% CI 0.92-4.14, P = 0.08), and patients in the high SA/PA ratio group were significantly more likely to relapse than those in the low ratio group (HR = 2.26, 95% CI 1.04-4.91, P = 0.04). Our findings suggest that the SA/PA ratio on day 7 after HSCT is an excellent biomarker to predict both aGVHD and relapse. The serum SA/PA ratio measured on day 7 after transplantation may improve risk stratification for aGVHD and relapse after allogeneic stem cell transplantation. National Natural Science Foundation of China (81470346, 81773361), Priority Academic Program Development of Jiangsu Higher Education Institutions, Jiangsu Natural Science Foundation (BK20161204), Innovation Capability Development Project of Jiangsu Province (BM2015004), Jiangsu Medical Junior Talent Person award (QNRC2016707), and NIH (AI129582 and NS106170).

Local Mesenchymal Stem Cell Therapy in Experimentally Induced Colitis in the Rat.

BackgroundMultipotent mesenchymal stem cells (MSCs) have been used in inflammatory bowel diseases because of their immunomodulatory and regenerative properties. We investigated their local use in an experimental model of colitis in the rat.Materials and MethodsColitis was induced into 20 Wistar rats with local TNBS instillation. Allogeneic stem cells were derived from rat adipose tissue and labeled with PKH2 linker dye with creation of a control and a second group treated by a local injection into the rectal wall of 2×106 allogeneic adipose tissue-derived stem cells (ADSCs). The thicknesses of different components of the rectum were measured with comparisons made in different parts of the colon of the Hunter inflammatory score. PKH2-dyed ADSCs were detected by fluorescence microscopy.Results and ConclusionsTotal colitis was induced in 19/20 rats with homing of fluorescent ADSCs. to the crypt base and perivascular space of the submucosa. There were no differences in component rectal wall thicknesses with a higher Hunter score in the treated group compared with the controls, in the rectum (3.8±2.74 vs. 1.5±2.37, respectively; p=0.017) and in right colon (2.5±1.08 vs. 0.20±0.42, respectively; p=0.0001). Local colonic injection of allogeneic adipose stem cells. in experimental colitis is feasible and safe. There is demonstrable homing of cells in chemically-induced colitis both to the treated region and parts of the colon distant to the MSC treatment site. Such cells readily proliferate in vitro and could potentially be a source for future treatment of resistant disease.

354 Clinical Trial of Allogeneic Mesenchymal Stem Cells in Second Degree Burns: Prelim Results

354 Clinical Trial of Allogeneic Mesenchymal Stem Cells in Second Degree Burns: Prelim Results

Efficacy and safety evaluation of mobilization and collection of unrelated allogeneic peripheral blood stem cells

Objective To evaluate the efficacy and safety of the mobilization and collection of unrelated allogeneic peripheral blood stem cells. Methods The suitable stem cell mobilization plan was made in accordance with the hematopoietic stem cell mobilization plan of China Marrow Donor Program, the ruler of the hospital, and the donor's constitution. The unrelated allogeneic peripheral blood stem cells of 64 healthy donors were collected in the second Hospital of Shanxi Medical University from May 2012 to January 2017. The donor was infected one or several times with the mobilization agent granulocyte colony stimulating factor (G-CSF) by 5-10 μg·kg-1·d-1. After 3-4 days, peripheral blood hematopoietic stem cells were collected using COBE Spectra blood cell separator. Then, the effect and adverse reaction of donors were analyzed from different age and sex. Results It can achieve the acquisition requirements using 3 or 4 days of mobilization programs, mononuclear cells ≥ 5.0×108/kg, CD34+ cells ≥ 2.0×106/kg. The single acquisition success rate (the target acquisition of the number of mononuclear cells and CD34+) up to 65%, collection efficiency reached 52%, which could reduce the risk of donor and the cost of patients. The quality of donor stem cell of young was better than that of older persons. Sixteen donors (25%) had mild adverse reactions, and no special treatment was required. Conclusions Allogeneic stem cell mobilization is safe. Starting from save medical resources and the interests of the donor the 3 day or 4 days of mobilization scheme could improve the success rate of the single mobilization. During the collection process, the condition of donor hypocalcemia should be observed and health education should be given to relieve the tension of donor. Key words: Hematopoietic stem cell mobilization; Collection; Efficacy; Safety

Restoration of limited defects of the cartilage with the use of cell-engineered constructs

Aim: to develop a three-dimensional composite cell-engineered constructs (CEC) for restoration of limited defects of the cartilage in experiment.Materials and methods. To create a cell-engineered constructs (CEC), were used collagenic carriers: «Chondro Gide» impermeable bilayer membrane and «Osteoplast» permeable matrix. A comparative study of their cytotoxic and adhesion properties was made in vitro. Chondroplastic potential of prepared CECs based on collagenous matrices with allogeneic mesenchymal stem cells (MSC) of the rabbit bone marrow grown on their surface was assessed in vivo. A cylindrical defect of the cartilage of the medial femoral condyle 3.3 mm in diameter at a depth of 1.5 mm was formed on both rabbit feet. Laboratory animals were divided into 3 groups: control group; Experiment 1 group with Chondro Gide used as the MSC carrier within CEC; Experiment 2 group using Osteoplast matrix. Upon experiment completion, a morphometric and histomorphologic research of tissue specimens was made. For statistical evaluation of the results a defect region recovery factor (RF) was offered and used. Results. After a 6-month observation period the control group showed partial recovery of the defect region with the recovery factor (RF) of 0.62 ± 0.06. The RF in Experiment 1 group equalled to 0.79 ± 0.07, Experiment 2 group revealed RF at the level of 0.88 ± 0.02. Statistical analysis of the research results shows that the use of CEC used in Experiment 2 group reduces a relative risk of therapeutic failures by 92.9%, and absolute risk – by 43.3% as compared to Experiment 1 group. Histomorphologic research data are indicative of a hyaline cartilage formation in the central defect zone, which is partially close to the intact cartilage to the maximum with zonality marked.Conclusion. Results of the research of the developed three-dimension cell-engineered constructs consisting of mesenchymal stem cells of the bone marrow grown on the Osteoplast permeable collagenic matrix show the formation of a cartilaginous hyaline tissue with a high level of structural organization in the area of its implantation. The thickness of a newly formed cartilage is insignifi cantly less than that of the preceding cartilaginous tissue, thus facilitating a dynamic distribution of the axial load on the articular surface, and as a whole this holds out hope for good long-term results. Therefore, based on the data obtained, we consider it reasonable to perform next investigation phases of the offered cell-engineered constructs for chondroplasty of limited cartilage defects.