Peripheral Blood-derived Stem Cells Research Articles

Allogeneic hematopoietic stem-cell transplantation for patients with Richter transformation: a retrospective study on behalf of the Chronic Malignancies Working Party of the EBMT.

Management of Richter transformation (RT) is particularly challenging, with survival estimates <1 year. We report on outcomes of 66 RT patients undergoing allogeneic-HCT (allo-HCT) between 2008 and 2018 registered with the EBMT. Median age at allo-HCT was 56.2 years (interquartile range (IQR), 51.3-63.1). Median time from RT to allo-HCT was 6.9 months (IQR, 4.9-11) and 28 (42.4%) were in complete remission (CR). The majority underwent reduced intensity conditioning (66.2%) using peripheral blood derived stem cells. Eighteen (27.3%) patients had a matched sibling donor, 24 (36.4%) a matched unrelated donor and the remaining were mismatched. Median follow-up was 6.6 years; 1- and 3- year overall and progression free survival (PFS) (95% CI) was 65% (54-77) and 39% (27-51) and 53% (41-65) and 29% (18-40), respectively. Patients in CR at time of allo-HCT had significantly better 3-year PFS (39% vs. 21%, p = 0.032). Cumulative incidences of grade II-IV acute graft versus host disease (GVHD) at day +100 was 41% (95% CI 29-53) and chronic GVHD at 3years was 53% (95% CI 41-65). High rates of non-relapse mortality (NRM) were observed; 38% (95% CI, 26-50) at 3 years. Although potentially curative, approaches to reduce considerable NRM and chronic GVHD rates are required.

Bovine Peripheral Blood-Derived Mesenchymal Stem Cells (PB-MSCs) and Spermatogonial Stem Cells (SSCs) Display Contrasting Expression Patterns of Pluripotency and Germ Cell Markers under the Effect of Sertoli Cell Conditioned Medium.

In vitro gamete derivation has been proposed as an interesting strategy for treatment of infertility, improvement of genetic traits, and conservation of endangered animals. Spermatogonial stem cells (SSCs) are primary candidates for in vitro gamete derivation; however, recently, mesenchymal stem cells (MSCs) have also been proposed as candidates for germ cell (GCs) differentiation mainly due to their transdifferentiating capacity. The objective of the present study was to compare the potential for GC differentiation of bovine peripheral blood-derived MSCs (PB-MSCs) and SSCs under the effect of conditioned medium (CM) derived from Sertoli cells (SCs/CM). Samples were collected every 7 days for 21 days and analyzed for pluripotent, GC, and MSC marker expression. The absence of OCT4 and the increased (p < 0.05) expression of NANOG seems to play a role in SSC differentiation, whereas the absence of NANOG and the increased expression (p < 0.05) of OCT4 may be required for PB-MSC differentiation into GCs. SSCs cultured with SCs/CM increased (p < 0.05) the expression of PIWIL2 and DAZL, while PB-MSCs cultured under the same condition only increased (p < 0.05) the expression of DAZL. Overall, the patterns of markers expression suggest that PB-MSCs and SSCs activate different signaling pathways after exposure to SCs/CM and during differentiation into GCs.

Abstract A020: Neural stem cells expressing PTEN-L suppress glioblastoma invasion in vivo

Abstract A020: Neural stem cells expressing PTEN-L suppress glioblastoma invasion <i>in vivo</i>

Safety assessment of equine allogeneic tenogenic primed mesenchymal stem cells in horses with naturally occurring tendon and ligament injuries.

Mesenchymal stem cells provide a valuable treatment option in orthopedic injuries in horses. The aim of this study was to evaluate the hematological, biochemical, immunological and immunomodulatory parameters following intralesional treatment with tenogenic primed equine allogeneic peripheral blood-derived mesenchymal stem cells (tpMSCs) in client-owned horses with naturally occurring superficial digital flexor tendon (SDFT) and suspensory ligament (SL) injuries. The immunogenicity and immunomodulatory capacities of tpMSCs were assessed in a modified mixed lymphocyte reaction, including peripheral blood mononuclear cells (PBMCs) of 14 horses with SDFT and SL injuries after treatment with tpMSCs. In a second study, 18 horses with SDFT and SL injuries received either an intralesional injection with tpMSCs (n = 9) or no treatment (n = 9). The tpMSCs did not provoke a cellular immune response (p < 0.001) and were able to immunomodulate stimulated T lymphocytes (p < 0.001) in vitro. Therapeutic use of tpMSCs did not result in relevant hematologic or biochemical abnormalities. Both studies had a small sample size. No statistical analyses were performed in the second study. Fibrinogen was only analyzed in a single horse prior to treatment. Co-incubation of tpMSCs and PBMCs of horses that have been previously exposed to tpMSCs did not elicit a cellular immune response and tpMSCs were able to immunomodulate stimulated T lymphocytes. Intralesional treatment with tpMSCs did not provoke abnormal changes in hematological and biochemical parameters.

Isolation of Peripheral Blood-Derived Mesenchymal Stem Cells in Mares and Foals

Isolation of Peripheral Blood-Derived Mesenchymal Stem Cells in Mares and Foals

Equine allogeneic tenogenic primed mesenchymal stem cells: A clinical field study in horses suffering from naturally occurring superficial digital flexor tendon and suspensory ligament injuries.

Mesenchymal stem cells are an innovative therapeutic for various equine orthopaedic diseases, including soft tissue injuries. To evaluate the safety and efficacy of tenogenic primed equine allogeneic peripheral blood-derived mesenchymal stem cells (tpMSCs) in horses with naturally occurring superficial digital flexor tendon (SDFT) and suspensory ligament (SL) injuries. Multicentre, blinded, randomised, placebo-controlled clinical trial. One hundred client-owned horses with SDFT and SL injuries were randomised to receive an intralesional tpMSC (66) or saline (34) injection. Clinical and ultrasonographic evaluation was performed before treatment and on Days 56 ± 3 and 112 ± 3 after treatment. Long-term data on re-injury was collected up to 2 years after treatment. Significantly more tpMSC-treated horses achieved improvement in fibre alignment score (FAS) (100% vs. 54.5%, p < 0.001) and echogenicity (97.0% vs. 57.6%, p < 0.001) on Day 112 ± 3, and their lesion size decreased significantly (-27.6 ± 25.91 vs. -4.6 ± 26.64 mm2 , p < 0.001) compared to the placebo group. A FAS = 0 was achieved in 65% of tpMSC-treated horses, as compared to 9% of placebo-treated horses at Day 112 ± 3. The attending veterinarians reported no re-injury in 41 of 53 tpMSC and in 2 of 26 saline-treated horses available for long-term follow-up (p < 0.001). As this study consisted of client-owned horses, no samples for histology were collected. Long-term follow-up was only available for a subset of enrolled horses. The intralesional administration of tpMSCs was safe and improved the quality of healing and long-term outcomes in sports horses with naturally occurring SDFT and suspensory injuries.

Neue Arzneimittel für Großtiere 2022

In 2022, one novel pharmaceutical agent was released on the German market for horses or food-producing animals: An injection suspension for horses containing tenogenic primed equine allogeneic peripheral blood-derived mesenchymal stem cells as the active ingredient (RenuTend®) is now available. The authorization of one established veterinary active ingredient was extended to an additional species: The synthetic prostaglandin F2α-analogue cloprostenol (Syncroprost®) received approval for goats. Additionally, for 2 active ingredients (paracetamol, suxibuzone), drugs with a higher content of the active ingredient were launched on the market for horses and food-producing animals.

CircRNA-ZCCHC14 affects the chondrogenic differentiation ability of peripheral blood-derived mesenchymal stem cells by regulating GREM1 through miR-181a

circRNAs play an important role in the progression of osteoarthritis (OA). Therefore, we aimed to reveal the mechanism of action of circRNA-ZCCHC14 in OA. OA animal and cell models were constructed, and clinical samples were collected. The expression of circRNA-ZCCHC14 and miR-181a was detected by RT‒qPCR. The chondrogenic differentiation ability of peripheral blood-derived mesenchymal stem cells (PBMSCs) was detected by Alcian blue staining. The expression of chondrogenic differentiation-related proteins was detected by Western blotting. Double fluorescein experiments verified the targeting relationship of miR-181a with circRNA-ZCCHC14 and GREM1. Upregulation of circRNA-ZCCHC14 was observed in blood, in BMP-2- and TGF-β3-treated PBMSCs from OA patients and in animal models. Knockdown of circRNA-ZCCHC14 promoted the chondrogenic differentiation ability of PBMSCs. circRNA-ZCCHC14 was found to bind to miR-181a and negatively regulate miR-181a expression. Inhibition of miR-181a reversed the promoting effect of circRNA-ZCCHC14 knockdown on the chondrogenic differentiation ability of PBMSCs. GREM1 was identified as a target of miR-181a. Overexpression and knockdown of GREM1 regulated the expression of BMP2, which in turn affected the chondrogenic differentiation ability of PBMSCs, indicating that GREM1 and BMP2 have antagonistic effects and that they jointly regulate the chondrogenic differentiation of PBMSCs. circRNA-ZCCHC14 may promote the chondrogenic differentiation ability of PBMSCs by regulating miR-181a and inhibiting the expression of GREM1.

Glucose-6-phosphate dehydrogenase is dispensable for human erythroid cell differentiation in vitro

Glucose-6-phosphate dehydrogenase (G6PD) deficiency impairs cellular processes under oxidative stress. Individuals with severe G6PD deficiency still produce sufficient numbers of erythrocytes. Nevertheless, the G6PD independence of erythropoiesis remains questionable. This study elucidates the effects of G6PD deficiency on the generation of human erythrocytes. Peripheral blood-derived CD34-positive hematopoietic stem and progenitor cells (HSPCs) of human subjects with normal, moderate, and severe G6PD activities were cultured in two distinct phases: erythroid commitment and terminal differentiation. Regardless of G6PD deficiency, HSPCs were able to proliferate and differentiate into mature erythrocytes. There was no impairment in erythroid enucleation among the subjects with G6PD deficiency. To our knowledge, this study is the first report of effective erythropoiesis independent of G6PD deficiency. The evidence firmly indicates that the population with the G6PD variant could produce erythrocytes to an extent similar to that in healthy individuals.

Identification of cell-biologic mechanisms of coronary artery spasm and its ex vivo diagnosis using peripheral blood-derived iPSCs

BackgroundAlthough vasospastic angina (VSA) is known to be caused by coronary artery spasm, no study has fully elucidated the exact underlying mechanism. Moreover, in order to confirm VSA, patients should undergo invasive coronary angiography with spasm provocation test. Herein, we investigated the pathophysiology of VSA using peripheral blood-derived induced pluripotent stem cells (iPSCs) and developed an ex vivo diagnostic method for VSA.Methods and resultsWith 10 mL of peripheral blood from patients with VSA, we generated iPSCs and differentiated these iPSCs into target cells. As compared with vascular smooth muscle cells (VSMCs) differentiated from iPSCs of normal subjects with negative provocation test, VSA patient-specific iPSCs-derived VSMCs showed very strong contraction in response to stimulants. Moreover, VSA patient-specific VSMCs exhibited a significant increase in stimulation-induced intracellular calcium efflux (Changes in the relative fluorescence unit [ΔF/F]; Control group vs. VSA group, 2.89 ± 0.34 vs. 10.32 ± 0.51, p < 0.01), and exclusively induced a secondary or tertiary peak of calcium efflux, suggesting that those findings could be diagnostic cut-off values for VSA. The observed hyperreactivity of VSA patient-specific VSMCs were caused by the upregulation of sarco/endoplasmic reticulum Ca2+-ATPase 2a (SERCA2a) due to its enhanced small ubiquitin-related modifier (SUMO)ylation. This increased activity of SERCA2a was reversed by treatment with ginkgolic acid, an inhibitor of SUMOylated E1 molecules (pi/µg protein; VSA group vs. VSA + ginkgolic acid, 52.36 ± 0.71 vs. 31.93 ± 1.13, p < 0.01).ConclusionsOur findings showed that abnormal calcium handling in sarco/endoplasmic reticulum could be induced by the enhanced SERCA2a activity in patients with VSA, leading to spasm. Such novel mechanisms of coronary artery spasm could be useful for drug development and diagnosis of VSA.

TIPE2 deletion improves the therapeutic potential of adoptively transferred NK cells

BackgroundTo enhance the efficacy of adoptive NK cell therapy against solid tumors, NK cells must be modified to resist exhaustion in the tumor microenvironment (TME). However, the molecular checkpoint underlying...

Construction of Vascularized Tissue Engineered Bone with nHA-Coated BCP Bioceramics Loaded with Peripheral Blood-Derived MSC and EPC to Repair Large Segmental Femoral Bone Defect

The regenerative repair of segmental bone defect (SBD) is an urgent problem in the field of orthopedics. Rapid induction of angiogenesis and osteoinductivity after implantation of scaffold is critical. In this study, a unique tissue engineering strategy with mixture of peripheral blood-derived mesenchymal stem cells (PBMSC) and endothelial progenitor cells (PBEPC) was applied in a 3D-printed biphasic calcium phosphate (BCP) scaffold with highly bioactive nano hydroxyapatite (nHA) coating (nHA/BCP) to construct a novel vascularized tissue engineered bone (VTEB) for rabbit femoral SBD repair. The 2D coculture of PBMSC and PBEPC showed that they could promote the osteogenic or angiogenic differentiation of the cells from each other, especially in the group of PBEPC/PBMSC = 75:25. Besides, the 3D coculture results exhibited that the nHA coating could further promote PBEPC/PBMSC adhesion, proliferation, and osteogenic and angiogenic differentiation on the BCP scaffold. In vivo experiments showed that among the four groups (BCP, BCP-PBEPC/PBMSC, nHA/BCP, and nHA/BCP-PBEPC/PBMSC), the nHA/BCP-PBEPC/PBMSC group induced the best formation of blood vessels and new bone and, thus, the good repair of SBD. It revealed the synergistic effect of nHA and PBEPC/PBMSC on the angiogenesis and osteogenesis of the BCP scaffold. Therefore, the construction of VTEB in this study could provide a possibility for the regenerative repair of SBD.

Kartogenin‐Conjugated Double‐Network Hydrogel Combined with Stem Cell Transplantation and Tracing for Cartilage Repair (Adv. Sci. 35/2022)

Cartilage Regeneration PEG-CHI-KGN DN gel combined with peripheral blood-derived mesenchymal stem cells (PB-MSCs) is employed in treating knee cartilage defects. Compared with current tissue-engineering products, it has unique strength because of optimized mechanics, high biosafety, and a simple preparation process. PEG-CHI-KGN DN gel promote the chondrogenic differentiation and survival of allogenic PB-MSCs, ultimately enhancing cartilage regeneration and providing an innovative clinical treatment strategy from the tissue-engineering perspective. More details can be found in article number 2105571 by De-Cheng Wu, Xing Wang, Jia-Kuo Yu, and co-workers.

Specific Cytogenetic Abnormalities at Diagnosis Predict Survival after Hematopoietic Cell Transplant in Poor-Risk Pediatric Acute Myeloid Leukemia: A PDWP/EBMT Study

Introduction: Cytogenetic abnormalities are an important prognostic factor for predicting overall survival (OS) and relapse incidence (RI) in children with acute myeloid leukemia (AML). Although allogeneic hematopoietic cell transplant (HCT) is generally recommended for patients with AML in first complete remission (CR1) and poor-risk (PR) cytogenetics, whether these cytogenetic and molecular features retain their prognostic value after HCT is unknown. Additionally, PR AML is a heterogeneous category that includes several distinct cytogenetic abnormalities, some of which might have a worse prognosis than others. In this study, we evaluated whether the cytogenetic risk classification at diagnosis of AML was predictive of post-HCT outcomes in pediatric patients. Methods: All patients <18 years of age at the time of HCT reported to the European Society for Blood and Marrow Transplantation (EBMT) registry, who had received their first allogeneic HCT for AML in CR1 between 2005 and 2020, and who had their karyotype evaluation at diagnosis available were included in this analysis. Patients were subgrouped as (a) monosomy 7/del7q or monosomy 5/del5q, (b) 11q23 abnormality excluding t(9;11), (c) complex or monosomal karyotype, or (d) other. A complex karyotype was defined as one with three or more structural abnormalities, and a monosomal karyotype was defined as a monosomy with one or more structural abnormalities, excluding WHO-designated recurring translocations or inversions based on 2017 ELN recommendations. Other cytogenetic abnormality subgroup included t(6;9), t(3;5), t(9;22), t(8;16), inv(3) or t(3;3), t(16;21), abn(11p15), and del(12p) or abn(12p13). Cytogenetic subgroup, age at HCT, whether HCT was from a female donor to a male recipient, patient/donor CMV status, time from AML diagnosis to HCT, and year of HCT were included as predictors for OS, RI and non-relapse mortality (NRM) in the multivariate analysis. Results: We included 744 pediatric patients (42.2% female; median age at HCT: 8.6 years [range: 0.3-18 years]) from 139 participating centers in the study. Median follow-up after HCT was 4.4 years. Thirty-seven percent had an 11q23 abnormality, 24% had monosomy 7/del7q or monosomy 5/del5q, 24% had a complex or monosomal karyotype, and 15% met the criteria for other PR cytogenetic abnormalities. Only 7% had secondary AML. Pre-HCT minimal residual disease (MRD) data were available for 346 patients, 86% of whom were MRD negative at the time of HCT. Patients received grafts from a matched related donor (27%), a mismatched related donor (11%), an unrelated donor (46%), or a cord blood donor (16%). Of the total patients, 55% received bone marrow, 29% received peripheral blood-derived stem cells and the rest (16%) received cord blood as the stem cell source. Myeloablative conditioning was used in 97% of the patients. The OS and leukemia free survival for the entire cohort was 76% and 70% respectively at 2 years. In a multivariate model, 11q23 (hazard ratio [HR] = 0.59, P = 0.01) and other poor-risk cytogenetic abnormalities (HR = 0.49, P < 0.01) were associated with significantly better OS when compared with monosomy 7/del7q or monosomy 5/del5q. The "other PR cytogenetic abnormalities" category was also associated with a lower risk of disease relapse after HCT (HR = 0.4, P = 0.01). Receiving an HCT from an unrelated donor, as compared with a matched related donor, was associated with lower RI (HR = 0.58, P = 0.03). Additionally, older age at HCT (12-18 years) was associated with the highest risk of NRM (HR = 1.95, P = 0.02) and with worse OS (HR = 1.71, P < 0.01) than seen in younger patients (aged 4-12 years). Conclusion: PR cytogenetic abnormalities at diagnosis remain predictive of OS after HCT for AML in pediatric patients. Monosomy 7/del7q or monosomy 5/del5q confer a poor prognosis even after HCT, whereas 11q23 abnormality and other PR cytogenetic abnormalities predict a favorable outcome after HCT. Our data also suggest that an HCT from an unrelated donor may offer greater protection against relapse than an HCT from a matched related donor, but this requires further validation. Efforts for improving conditioning regimens and transplant techniques should focus on reducing NRM and reducing RI in this population. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Kartogenin-Conjugated Double-Network Hydrogel Combined with Stem Cell Transplantation and Tracing for Cartilage Repair.

The effectiveness of existing tissue-engineering cartilage (TEC) is known to be hampered by weak integration of biocompatibility, biodegradation, mechanical strength, and microenvironment supplies. The strategy of hydrogel-based TEC holds considerable promise in circumventing these problems. Herein, a non-toxic, biodegradable, and mechanically optimized double-network (DN) hydrogel consisting of polyethylene glycol (PEG) and kartogenin (KGN)-conjugated chitosan (CHI) is constructed using a simple soaking strategy. This PEG-CHI-KGN DN hydrogel possesses favorable architectures, suitable mechanics, remarkable cellular affinity, and sustained KGN release, which can facilitate the cartilage-specific genes expression and extracellular matrix secretion of peripheral blood-derived mesenchymal stem cells (PB-MSCs). Notably, after tracing the transplanted cells by detecting therabbit sex-determining region Y-linked gene sequence, the allogeneic PB-MSCs are found to survivefor even 3 months in the regenerated cartilage. Here, the long-term release of KGN is able to efficiently and persistently activate multiple genes and signaling pathways to promote the chondrogenesis, chondrocyte differentiation, and survival of PB-MSCs. Thus, the regenerated tissues exhibit well-matched histomorphology and biomechanical performance such as native cartilage. Consequently, it is believed this innovative work can expand the choice for developing the next generation of orthopedic implants in the loadbearing region of a living body.

Peripheral Blood-Derived Stem Cells for the Treatment of Cartilage Injuries: A Systematic Review

Background: The treatment of cartilage damage is a hot topic at present, and cell therapy is an emerging alternative therapy. Stem cells derived from peripheral blood have become the focus of current research due to the ease of obtaining materials and a wide range of sources. Methods: We used a text search strategy using the [“mesenchymal stem cells” (MeSH term) OR “MSC” OR “BMMSC” OR “PBMSC” OR” PBMNC” OR “peripheral blood stem cells”] AND (cartilage injury [MeSH term] OR “cartilage” OR “chondral lesion”). After searching the literature, through the inclusion and exclusion criteria, the last included articles were systematically reviewed. Result: We found that peripheral blood-derived stem cells have chondrogenic differentiation ability and can induce chondrogenic differentiation and repair in vivo and have statistical significance in clinical and imaging prognosis. It is an improvement of academic differences. Compared with the bone marrow, peripheral blood is easier to obtain, widely sourced, and simple to obtain. In the future, peripheral blood will be a more potential cell source for cell therapy in the treatment of cartilage damage. Conclusion: Stem cells derived from peripheral blood can repair cartilage and are an important resource for the treatment of cartilage damage in the future. The specific mechanism and way of repairing cartilage need further study.

Demineralized Cortical Bone Matrix Augmented With Peripheral Blood-Derived Mesenchymal Stem Cells for Rabbit Medial Meniscal Reconstruction.

Tissue engineering is a promising treatment strategy for meniscal regeneration after meniscal injury. However, existing scaffold materials and seed cells still have many disadvantages. The objective of the present study is to explore the feasibility of peripheral blood-derived mesenchymal stem cells (PBMSCs) augmented with demineralized cortical bone matrix (DCBM) pretreated with TGF-β3 as a tissue-engineered meniscus graft and the repair effect. PBMSCs were collected from rabbit peripheral blood and subjected to three-lineage differentiation and flow cytometry identification. DCBM was prepared by decalcification, decellularization, and cross-linking rabbit cortical bone. Various characteristics such as biomechanical properties, histological characteristics, microstructure and DNA content were characterized. The cytotoxicity and the effects of DCBM on the adhesion and migration of PBMSCs were evaluated separately. The meniscus-forming ability of PBMSCs/DCBM complex in vitro induced by TGF-β3 was also evaluated at the molecular and genetic levels, respectively. Eventually, the present study evaluated the repair effect and cartilage protection effect of PBMSCs/DCBM as a meniscal graft in a rabbit model of medial meniscal reconstruction in 3 and 6 months. The results showed PBMSCs positively express CD29 and CD44, negatively express CD34 and CD45, and have three-lineage differentiation ability, thus can be used as tissue engineering meniscus seed cells. After the sample procedure, the cell and DNA contents of DCBM decreased, the tensile modulus did not decrease significantly, and the DCBM had a pore structure and no obvious cytotoxicity. PBMSCs could adhere and grow on the scaffold. Under induction of TGF-β3, PBMSCs/DCBM composites expressed glycosaminoglycan (GAG), and the related gene expression also increased. The results of the in vivo experiments that the PBMSCs/DCBM group had a better repair effect than the DCBM group and the control group at both 12 and 24 weeks, and the protective effect on cartilage was also better. Therefore, the application of DCBM augmented with PBMSCs for meniscus injury treatment is a preferred option for tissue-engineered meniscus.

Peripheral Blood-Derived Mesenchymal Stem Cells Modulate Macrophage Plasticity through the IL-10/STAT3 Pathway.

Mesenchymal stem cells (MSCs) are multipotent cells that can skew the balance of M1/M2 macrophage polarization towards the M2 phenotype via their paracrine effects, thereby promoting anatomical and functional recovery after many inflammatory diseases induced by macrophages. However, the underlying mechanism is still poorly understood. This study focused on the IL-10/STAT3 pathway and investigated whether IL-10 secreted by PBMSCs could mediate M2 polarization through the activation of this pathway. In this study, a Transwell system was used for coculturing macrophages and PBMSCs. ELISA and RT-qPCR analysis found that PBMSCs and their conditioned media (P-CM) significantly induced the expression of IL-10, while significantly inhibiting the expression of IL-1β and TNF-α; moreover, this effect could be reversed by adding Ab9969 (an IL-10 neutralizing antibody) and Stattic (a STAT3 inhibitor). Furthermore, western blotting and immunofluorescence assays demonstrated that JAK1/STAT3 signaling was significantly upregulated in macrophages cocultured with PBMSCs or P-CM, accompanied by an increase in the M2 biomarker CD206 and a decrease in the M1 biomarker CD86. This effect could also be reversed by blocking the IL-10/STAT3 pathway with Ab9969 and Stattic. In summary, PBMSCs could mediate the polarization of M2 macrophages by activating the IL-10/STAT3 pathway.

PBMSCs transplantation facilitates functional recovery after spinal cord injury by regulating microglia/macrophages plasticity

BackgroundStem cell therapy has been proven as one of the promising strategies for treating spinal cord injury (SCI). However, the role of peripheral blood-derived mesenchymal stem cells (PBMSCs) in animal models of SCI has not been fully uncovered. This study aimed to investigate whether transplanted PBMSCs could inhibit neuroinflammation and then promote the functional recovery by shifting the microglia/macrophages phenotype from M1 to M2 at the site of injury after SCI. MethodsPBMSCs harvested from peripheral blood were analyzed by morphology and phenotype. Rat models of SCI were administrated with PBMSCs 1 week after injury. Inclined plane test and Basso-Beattie-Bresnahan (BBB) scores were used for assessing the functional recovery. Enzyme-linked immunosorbent assay (ELISA), reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and flow cytometry (FCM) were performed on days 3, 7, 14, 28 and 56 after PBMSCs transplantation. ResultsPBMSCs were plastic-adherent and fibroblast-like with positive expression of cluster of differentiation (CD)29, CD90 and CD44. ELISA and RT-qPCR both showed a lower expression of pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α while a higher expression of anti-inflammatory cytokines IL-10 and transforming growth factor (TGF)-β1 after PBMSCs transplantation. This was associated with increased numbers of M2 microglia/macrophages and decreased numbers of M1 microglia/macrophages. These changes taken together were associated with the functional recovery in PBMSCs groups. ConclusionsAdministration of PBMSCs following SCI may provide an anti-inflammatory and reparative micro-environment for locomotive recovery by shifting microglia/macrophages phenotype from M1 towards M2.

Severe Cytokine Release Syndrome Associated with Worse Outcomes in Recipients of a Haploidentical Stem Cell Transplant

Introduction: The utilization of haploidentical (haplo) donors for allogeneic hematopoietic stem cell transplant (HCT) recipients has allowed more donor options to treat a multitude of hematopoietic malignancies and disorders. However, there are substantial complications and morbidities associated with haplo HCT. Cytokine release syndrome (CRS), a manifestation of alloreactive T cell expansion, has posed an obstacle early after stem cell infusion. CRS is well described among chimeric antigen receptor (CAR) T cell therapy recipients, where anti-interleukin (IL) 6 therapy and glucocorticoids to abrogate cytokine activity depends on objective physiologic markers and neurologic changes. In 2019, the American Society of Transplantation and Cellular Therapy (ASTCT) developed a consensus CRS grading scale for CAR T cell therapy that has since been widely adopted for these recipients (Lee et al, Biol Blood Marrow Transpl 2019). While the etiology of CRS differs between haplo HCT and CAR T cell recipients, severe CRS (grade 3 or 4) is seen in both patient populations, defined by ASTCT CRS grading as non-fluid responsive hypotension and/or capillary leak necessitating increased ventilatory support. We investigated whether the newly adopted ASTCT CRS grading could apply to a haplo HCT population in predicting overall survival (OS) and progression-free survival (PFS) at 1 year as well as the 2-year probability of graft-versus-host disease (GVHD).Methods: This IRB-approved retrospective analysis assessed 64 patients who underwent haplo HCT at Colorado Blood Cancer Institute from July 2015 to December 2018. All but one patient received peripheral blood-derived stem cells, and all patients received post-transplant cyclophosphamide, tacrolimus, and mycophenolate mofetil for GVHD prophylaxis. Variables of birth sex, primary disease, disease risk index (DRI), blood type, degree of HLA-mismatching, presence of donor-specific antibodies, Hematopoietic Cell Transplant Comorbidity Index (HCT-CI), conditioning regimen, and cell dose were assessed. In all patients, fever, blood pressure, and oxygen supplementation were used to identify the maximum CRS grade between 0-5 days after HCT using ASTCT CRS grading. Patients with other etiologies (i.e. infection, cardiomyopathy) were excluded from the analysis. CRS grading was then dichotomized to mild (CRS grades 0-2) or severe (grades 3-4), reflecting the physiologic changes that align with minimal compared to intensive cardiopulmonary support. As all patients had complete follow-up to 2 years, logistic regression was used to estimate association between severe CRS and outcome.Results: When adjusted for age, DRI and HCT-CI, development of severe CRS was associated with an inferior PFS at 1 year (odds ratio (OR) 0.22, (95% Confidence Interval (CI) 0.07, 0.69), p = 0.01). Inferior OS was also seen in those who developed severe CRS but the magnitude of the effect was smaller and not considered definitive (OR 0.38, (95%CI 0.13, 1.13), p=0.082). Increased non-relapse mortality (NRM) was also seen with severe CRS. Due to the low number of events, adjustment for only one factor at a time was necessary. When adjusted for age (OR 2.94, (95%CI 0.82, 11.1), p=0.101), DRI (OR 3.23, (95%CI 0.91, 11.1), p=0.069), HCT-CI (OR 2.94, (95%CI 0.85, 10), p=0.089), and conditioning regimen (OR 3.23, (95%CI 0.91, 11.1), p=0.071), consistent results were demonstrated, although not definitive. This was also observed with the risk of relapse, adjusted for conditioning regimen (OR 2.56, (95%CI 0.76, 9.09), p=0.126) and DRI (OR 2.56, (95%CI 0.75, 8.33), p=0.132). There was no demonstrable association between CRS and the probability of acute GVHD. However, severe CRS was associated with a reduction in the development of any chronic GVHD at 2 years (OR 0.24, (95%CI 0.08, 0.72), p=0.011).Conclusion: This analysis suggests that an adapted ASTCT CRS grading, dichotomizing into those with mild (grades 0-2) or severe (grades 3-4) CRS may identify haplo HCT recipients at risk for inferior outcomes. Haplo HCT recipients with severe CRS demonstrated an inferior PFS. The data also showed numerical decreases in overall survival, higher relapse, and higher NRM. On the other hand, severe CRS was associated with a decreased probability of chronic GVHD. As the analysis was limited to a single site, validation of adapted ASTCT grading in a larger haplo HCT population is necessary. DisclosuresNo relevant conflicts of interest to declare.