Allogeneic Bone Marrow Mesenchymal Stem Cells Research Articles

The addition of mesenchymal stem cells in a bioabsorbable scaffold does not enhance tendon healing after a repair of rotator cuff tear.

The purpose of the study is to evaluate the healing potential of a full-thickness tendon defect in the rotator cuff of rabbits using a bioabsorbable scaffold impregnated with bone marrow-mesenchymal stem cells (BM-MSCs) or rotator cuff-derived mesenchymal stem cells (RC-MSCs). Sixteen adult rabbits were subjected to a full-thickness rotator cuff deficit. Rabbits were randomly assigned to four groups of four animals. In Group 0 (control), the deficit was left untreated. In Group 1, the deficit was treated with a single synthetic scaffold alone. In Group 2, the deficit was treated with the previous scaffold loaded with allogeneic BM-MSCs. In Group 3, the deficit was treated with the previous scaffold loaded with allogenic RC-MSCs. After animal sacrifice, tissue samples were subjected to histological and immunohistochemical analysis. Group 1 showed the highest mean tendon maturing score (15.3 ± 0.9) postoperatively, being significantly higher, in comparison to groups 0, 2 and 3 (p = 0.01, 0.02 and 0.01, respectively). Group 1 showed the highest mean collagen I/collagen III ratio (1.4 ± 0.8) postoperatively but without any statistical significance. The utilization of MSCs in rotator cuff repair in a rabbit model has not been associated with an enhancement in tendon healing in 16 weeks postoperatively, in comparison to controls and bioabsorbable scaffolds. The addition of MSCs does not result in better rotator cuff healing. Not applicable. This is an animal study.

Regenerative capacity of bone marrow stem cells on aged albino rat’s parotid excretory duct

ObjectiveTo appraise structural features of parotid excretory duct during senility and probable effect of bone marrow-mesenchymal stem cells (BM-MSCs). DesignA total of 14 healthy male albino rats were used. Seven adult rats (24–34-week-old) represented the control group (Group I). Seven senile rats (72–80-week-old) were utilized in which the left parotid gland served as “Old” (Group II) and were injected by 0.2 ml phosphate buffered saline; the right side represented “Old treated” (Group III) and got local injection of 1–1.5 million allogeneic BM-MSCs. One month later, glands were dissected and assessed structurally, ultra-structurally and statistically. ResultHistologically, Group I showed normal duct histology. In Group II duct lining lost its pseudostratification which was recovered in Group III. PCNA immunolocalization showed moderate reactivity in Group I, negative to mild reaction in Group II, and strong reaction in some of Group III cells. Ultra-structural features of Group I were ordinary in which basal cell had a large flat nucleus, and dark and light cells showed electron-dense cytoplasm and electron-lucent cytoplasm respectively. Tuft cell displayed long microvilli. Mucous droplets filled goblet cell. Group II revealed an apparent reduction in cells size, organelles and absence of tuft cell. In Group III all cell types were detected and they recovered their organelles, cell and nucleus shape. The highest mean area% of PCNA immunoreactivity was in Group I followed by Group III then Group II. ConclusionsAging has a deteriorating effect on structure and ultra-structure of parotid gland excretory duct that could be amended by BM-MSCs.

Allogeneic Bone-Marrow Mesenchymal Stem Cell with Moldable Cryogel for Craniofacial Bone Regeneration.

Allogeneic bone-marrow mesenchymal stem cells (BMSCs) can promote bone regeneration and substitute for autologous BMSCs if autologous sources are unavailable, but the efficacy of bone regeneration by allogeneic BMSCs is still inconsistent. A Lewis rat cranium defect model was used to investigate the efficacy of bone regeneration between autologous and allogeneic BMSCs in gelatin-nanohydroxyapatite cryogel scaffolds. BMSCs from Wistar rats served as the allogeneic cell lineage. The full-thickness cranium defects were treated by either blank control, cryogel only, allogeneic BMSC-seeded cryogel, or autologous BMSC-seeded cryogel (n = 5). Bone regeneration was monitored by micro-computed tomography and examined histologically at week 12. In addition, we assessed the immune responses in vitro by mixed lymphocyte reaction (MLR) assay and CD4+ immunochemistry staining ex vivo. The MLR showed that allogeneic BSMCs elicited a weak immune response on day 14 that progressively attenuated by day 28. In vivo, the bone regeneration in allogeneic BMSCs was inferior at week 4, but progressively matched the autologous BMSCs by week 12. Our results suggest that allogeneic BMSCs can serve as an alternative source for bone regeneration.

Experimental study on transplantation of microencapsulated transgenic bone marrow mesenchymal stem cells for early steroid-induced osteonecrosis of femoral head in rabbits

To investigate the effect of microencapsulated transgenic bone marrow mesenchymal stem cells (BMSCs) transplantation on early steroid induced osteonecrosis of femoral head (SONFH) in rabbits. Alginate poly- L-lysine-sodium alginate (APA) microencapsulated transgenic BMSCs with high expression of Foxc2 were prepared by high-voltage electrostatic method. Part of the cells were cultured in osteoblasts and observed by alizarin red staining at 2 and 3 weeks. Forty New Zealand white rabbits were used to prepare SONFH models by using hormone and endotoxin. Thirty two rabbits who were successful modeling were screened out by MRI and randomly divided into 4 groups (groups A, B, C and D, n=8); another 6 normal rabbits were taken as normal control (group E). The rabbits in group A did not receive any treatment; and in groups B, C, and D were injected with normal saline, allogeneic BMSCs, and APA microencapsulated transgenic BMSCs respectively after core decompression. At 6 and 12 weeks after operation, specimens of femoral head were taken for HE staining to observe bone ingrowth; the expressions of osteocalcin (OCN), peroxisome proliferative activated receptor γ 2 (PPARγ-2), and vascular endothelial growth factor (VEGF) proteins were observed by immunohistochemistry staining. At 12 weeks after operation, the bone microstructure was observed by transmission electron microscope, and the maximum compressive strength and average elastic modulus of cancellous bone and subchondral bone were measured by biomechanics. After 2 and 3 weeks of induction culture, alizarin red staining showed the formation of calcium nodules, and the number of calcium nodules increased at 3 weeks when compared with 2 weeks. The rabbits in each group survived until the experiment was completed. Compared with groups A, B, and C, the trabeculae of group D were more orderly, the empty bone lacunae were less, there were abundant functional organelles, and obvious osteogenesis was observed, and the necrotic area was completely repaired at 12 weeks. Immunohistochemical staining showed that, at 6 and 12 weeks after operation, the expressions of OCN and VEGF in groups A, B, and C were significantly lower than those in groups D and E, while those in groups B and C were significantly higher than those in group A, and in group E than in group D ( P<0.05). The expression of PPARγ-2 was significantly higher in groups A, B, and C than in groups D and E, and in group A than in groups B and C, and in group D than in group E ( P<0.05). At 12 weeks after operation, biomechanical test showed that the average elastic modulus and maximum compressive strength of cancellous bone and subchondral bone in groups D and E were significantly higher than those in groups A, B, and C ( P<0.05); there was no significant difference between groups A, B, and C and between groups D and E ( P>0.05). In vivo transplantation of microencapsulated transgenic BMSCs can repair early SONFH in rabbits.

Effects of local injection and intravenous injection of allogeneic bone marrow mesenchymal stem cells on the structure and function of damaged anal sphincter in rats.

Anal sphincter injury leads to damage to the anal structure and functions and has been identified as a major risk factor for fecal incontinence. Bone marrow mesenchymal stem cells (BMSCs) with capacities of multidifferentiation, paracrine, and low immunogenicity have been widely used in tissue repair and regeneration. The primary objective of this research was to compare the effects of different injection therapies of BMSCs on the injured anal sphincters. Ninety-six Sprague-Dawley female rats were randomly divided into four groups (n = 24 each): intravenous injection, local injection, sham operation, and normal control. For the first three groups, 25% removal of the anal sphincter complex was performed and 0.3-ml phosphate-buffered saline (PBS) (containing 107 green fluorescent protein-labeled allogeneic BMSCs) was given accordingly to the treatment group 24 h after operation for 7 consecutive days. The sham operation group was injected with 0.3-ml PBS only. All cases had undergone evaluation in the 1st, 7th, 14th, and 28th postoperative days. The rats were sacrificed on the 28th postoperative day, and the anal sphincters were dissected to be analyzed by morphological examination. At 14 days postoperatively, local injection of BMSC significantly improved the peak contraction pressure, electromyography amplitude, and frequency of the injured anal sphincter compared with tail vein, but there was no significant difference in resting pressure until 28 days after sphincterectomy. Masson staining results confirmed that the local injection group had significantly more new muscles on the wound. BMSC could remarkably improve peak contraction pressure, electromyography amplitude, and muscle fibers on the wound, and local injection is superior to intravenous injection.

Testosterone propionate can promote effects of acellular nerve allograft‐seeded bone marrow mesenchymal stem cells on repairing canine sciatic nerve

Peripheral human nerves fail to regenerate across long tube implants (>2cm), and tissue-engineered nerve grafts represent a promising treatment alternative. The present study aims to investigate the testosterone propionate (TP) repair effect of acellular nerve allograft (ANA) seeded with allogeneic bone marrow mesenchymal stem cells (BMSCs) on 3-cm canine sciatic nerve defect. ANA cellularized with allogeneic BMSCs was implanted to the defect, and TP was injected into the lateral crus of the defected leg. The normal group, the autograft group, the ANA+BMSCs group, the ANA group, and the nongrafted group were used as control. Five months postoperatively, dogs in the TP+ANA+BMSCs group were capable of load bearing, normal walking, and skipping, the autograft group and the ANA+BMSCs group demonstrated nearly the same despite a slight limp. The compound muscle action potentials (CMAPs) on the injured side to the uninjured site in the TP+ANA+BMSCs group were significantly higher than that in the ANA+BMSCs group [CMAPs ratio at A: F(3, 20)=191.40; 0.02, CMAPs ratio at B: F(3, 20)=43.27; 0.01]. Masson trichrome staining revealed that in the TP+ANA+BMSCs group, both the diameter ratio of the myelinated nerve and the thickness ratio of regenerated myelin sheath were significantly larger than that in the other groups [the diameter of myelinated nerve fibers: F(3, 56)=13.45; P<.01, the thickness ratio of regenerated myelin sheath: F(3, 56)=51.25; P<.01]. In conclusion, TP could significantly increase the repairing effects of the ANA+BMSCs group, and their combination was able to repair 3-cm canine sciatic nerve defect. It therefore represents a promising therapeutic approach.

Restoration of osteochondral defects by implanting bilayered poly(lactide-co-glycolide) porous scaffolds in rabbit joints for 12 and 24 weeks

BackgroundWith the ageing of the population and the increase of sports injuries, the number of joint injuries has increased greatly. Tissue engineering or tissue regeneration is an important method to repair articular cartilage defects. While it has recently been paid much attention to use bilayered porous scaffolds to repair both cartilage and subchondral bone, it is interesting to examine to what extent a bilayer scaffold composed of the same kind of the biodegradable polymer poly(lactide-co-glycolide) (PLGA) can restore an osteochondral defect. Herein, we fabricated bilayered PLGA scaffolds and used a rabbit model to examine the efficacy of implanting the porous scaffolds with or without bone marrow mesenchymal stem cells (BMSCs). The present manuscript reports the regenerative potential up to 24 weeks. MethodsThe osteochondral defect, 4 mm in diameter and 5 mm in depth, was created in the medial condyle of each knee in 23 rabbits. The bilayered PLGA scaffolds with a pore size of 100–200 μm in the chondral layer and a pore size of 300–450 μm in the osseous layer, seeded with or without BMSCs in the chondral layer, were then transplanted into the osteochondral defect of each knee. The osteochondral defect created in the same manner was untreated to act as the control. At 12 and 24 weeks postoperatively, condyles were harvested and analyzed using histology, immunohistochemistry, real-time polymerase chain reaction, and biomechanical testing to evaluate the efficacy of osteochondral repair. ResultsNo joint erosion, inflammation, swelling, or deformity was observed, and all animals maintained a full range of motion. Compared with the untreated blank group, the groups implanting the bilayered scaffolds with or without cells exhibited much better resurfacing, similar to the surrounding normal tissue. The histological scores of neotissues repaired by the scaffold with cells were closer to that of normal tissue. Although the biomechanical properties of neotissues were not as good as the normal tissue, no significant difference was found between the gene levels of neotissues repaired by the scaffold with or without cells and that of the normal tissue. The repair of the osteochondral defect tends to be stable 12 weeks after implantation. ConclusionsOur bilayered PLGA porous scaffold supports long-term osteochondral repair via in vivo tissue engineering or regeneration, and its effect can be further facilitated under the scaffold seeded with allogenic BMSCs. The translational potential of this articleThe bilayered PLGA porous scaffold can facilitate the repair of osteochondral defects and has potential for application in osteochondral tissue engineering.

A systematic review of the treatment of knee osteoarthritis with intraarticular injection of mesenchymal stem cells

Background: A wide array of treatment, both surgical and nonsurgical, exists for osteoarthritis (OA) of the knee. Injectable stem-cell therapy represents a minimally invasive and potentially efficacious treatment; however, there have been no level I studies conducted on this specific application of stem-cell therapy. The purpose of our review was to analyze, report, and summarize current topical data. Methods: A systematic review of the treatment of human knee OA with mesenchymal stem cells (MSCs) was performed by searching PubMed/Medline and Google Scholar. Non-human studies and studies involving additional procedures were excluded. Authors reviewed the studies individually, with the primary author deciding on inclusion. Results: Our search ultimately returned 10 studies that met the inclusion criteria. Nine of the ten studies used cultured autologous MSCs, five from bone marrow, three from subcutaneous fat, and one from peripheral blood. The remaining study used allogenic bone marrow MSCs. Radiographic analysis of cartilage quality via MRI T2 mapping showed increased type II collagen production in five studies. Outcome scores consistently showed pain reduction and improved function. No study reported significant adverse events related to stem-cell therapy. Conclusions: Current human studies evaluating the use of injected MSCs for knee OA demonstrated consistent improvement across several outcome scores, with no significant adverse findings. Level of Evidence: Level IV, systematic review of Level II-IV trials and studies.

Effects of bone marrow mesenchymal stem cell transplantation on the expression of stromal cell-derived factor-1α and vascular endothelial growth factor in rats with acute hepatic failure

Objective: To investigate the curative effect of bone marrow mesenchymal stem cells (BMSCs) transplantation on the expression of stromal cell-derived growth factor (SDF-1 α) and vascular endothelial growth factor (VEGF) in rats with acute hepatic failure, and to compare the effects of two transplantation pathways. Methods: Eighty-four rats with acute liver failure (ALF) induced by D-galactosamine combined with lipopolysaccharide were randomly divided into control group, tail vein and portal vein transplantation group. The latter two groups were injected allogenic BMSCs into the tail vein and portal vein. Blood samples and liver tissue samples were collected at 24, 72, 120, and 168h after transplantation to detect serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The improvement of liver function before and after BMSCs transplantation was compared. The expression of VEGF and SDF-1a in liver tissue was detected by immunofluorescence and Western blot. Data measurement between two groups was performed by analysis of variance and the correlation analysis was performed by Spearman's rank correlation coefficient. Results: Serum ALT and AST levels in the tail vein and portal vein transplantation group peaked at 24 h after transplantation, which were (134.60 ± 58.08 IU/L), (179.20 ± 86.68 IU/L), and (131.00 ± 54.47 IU/L), (173.50 ± 93.10 IU/L). In addition, 168h after transplantation it decreased to (46.10 ± 8.40 IU/L), (95.67 ± 13.80 IU/L) and (19.30 ± 1.30 IU/L), (54.30 ± 6.00 IU/L). After 120 and 168 hours of BMSCs transplantation, the levels of serum ALT and AST in tail vein and portal vein transplantation group were significantly higher than control group (F ≥ 12.51, P < 0.01). The results of western blot and immunofluorescence showed that the expression levels of SDF-1α and VEGF protein in the two BMSCs transplantation groups increased with the improvement of liver function, and the difference was statistically significant at 120 and 168 hours after transplantation (F ≥ 9.069, P < 0.05). There was no significant difference in the expression of SDF-1a and VEGF between the tail vein and portal vein transplantation groups (P > 0.05). Correlation analysis showed that the expression levels of SDF-1α and VEGF in liver tissues were positively correlated (r = 0.923, P < 0.05). Conclusion: BMSCs transplantation can promote the secretion of VEGF for recovery of liver function to reduce the degree of inflammation and necrosis in rats with ALF.

BIOMECHANIC STUDY OF GRAFT BONE TUNNEL MODEL IN ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION USING INTRATUNNEL ALLOGENIC BONE MARROW MESENCHYMAL STEM CELLS (BM-MSCs) AND VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF)

Successful anterior cruciate ligament (ACL) reconstruction using tendon graft requires good and rapid integration between the tendon graft and the bone tunnel. The strength of the tendon-bone tunnel graft in the initial phase is very important to facilitate aggressive rehabilitation and as early as possible to support rapid recovery to normal activities. The objective of this study was to determine ultimate tension strength (UTS) on the femoral tendon-bone tunnel graft model after reconstruction of anterior cruciate ligament (ACL) by administering allogenic bone marrow mesenchymal stemcells (BM-MSCs) and vascular endothelial growth factor (VEGF) intratunnel in experimental animals. The design of this research was Post-Test Only Control Group Design using 24 rabbits divided into treatment and control group. Biomechanical evaluation was done at week 3 and 6. Evaluation at week 3 found ultimate tension strength of treatment group significantly higher than control (p &lt;0,05). In the 6th week evaluation, Ultimate tension strength was found that the treatment group significantly higher than the control group (p &lt;0.05). Ultimate tension strength at week 3 did not differ significantly with week 6 (p&gt; 0.05). Intravenous administration of BM-MSCs and VEGF on ACL reconstruction increased ultimate tension strength in graft-bone tunnel significantly since week 3. The study of Ferdiansis et al using BM-MSCs and VEGF intraarticular, only showed a significant increase in ultimate tension strength in graft-bone tunnel since week 6. Comparison of this method indicates acceleration in incorporation of tendon graft with bone tunnel on intratunnel method better thaninvitro intraarticular method.Keywords : Anterior cruciate ligament, allogenic bone marrow mesenchymal stem cells, vascular endothelial growth factor and biomechanic study.

COLLAGEN ANALYSIS OF GRAFT IN BONE TUNNEL MODEL ANTERIOR CRUCIATE LIGAMENT (ACL) RECONSTRUCTION WITH INTRATUNNEL ALLOGENIC BONE MARROW MESENCHYMAL STEM CELLS (MSCs) AND VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF)

ACL reconstruction measures aim to obtain stable knees, and reduce the risk of further injury to the meniscus and joint surfaces. Acceleration of the integration process between the tendon graft and the bone tunnel will improve the final result of ACL reconstruction. The purpose of this study was to investigate the collagen composition of the bone tunnel graft model of anterior cruciate ligament reconstruction with intravenous allogenic bone marrow mesenchymal stem cells and vascular endothelial growth factor in experimental animals. The design of this study was Post-test only Control Group Design using 20 rabbits divided into treatment group and control group. Collagen immunohistochemical evaluation was performed at weeks 3 and 6. Evaluation at week 3 obtained the area of collagen type-1 in the higher treatment group at treatment (p &lt;0.001). In the 6th week evaluation, it was found that the area of collagen type-1 in the treatment group was higher (p &lt;0.05). Type-1 collagen at week 6 did not differ significantly with week 3 (p&gt; 0.05). Provision of allogenic bone marrow mesenchymal stem cells and intratonal vascular endothelial growth factor in ACL reconstruction enhanced the formation of collagen type-1 which is the acceleration of incorporation of the graft tendon process with bone tunnel.Keywords : Anterior Cruciate Ligament, allogenic bone marrow mesenchymal stemcells, vascular endothelial growth factor, graft and collagen.

Mesenchymal Stem Cells in Combination with Hyaluronic Acid for Articular Cartilage Defects

Mesenchymal stem cells (MSCs) and hyaluronic acid (HA) have been found in previous studies to have great potential for medical use. This study aimed to investigate the therapeutic effects of bone marrow mesenchymal stem cells (BMSCs) combined with HA on articular cartilage repair in canines. Twenty-four healthy canines (48 knee-joints), male or female with weight ranging from 5 to 6 kg, were operated on to induce cartilage defect model and divided into 3 groups randomly which received different treatments: BMSCs plus HA (BMSCs-HA), HA alone, and saline. Twenty-eight weeks after treatment, all canines were sacrificed and analyzed by gross appearance, magnetic resonance imaging (MRI), hematoxylin-eosin (HE) staining, Masson staining, toluidine blue staining, type II collagen immunohistochemistry, gross grading scale and histological scores. MSCs plus HA regenerated more cartilage-like tissue than did HA alone or saline. According to the macroscopic evaluation and histological assessment score, treatment with MSCs plus HA also lead to significant improvement in cartilage defects compared to those in the other 2 treatment groups (P < 0.05). These findings suggested that allogeneic BMSCs plus HA rather than HA alone was effective in promoting the formation of cartilage-like tissue for repairing cartilage defect in canines.

Effects of inhalation and intravenous administration of allogeneic mesenchymal bone marrow stromal cells in a bleomycin-induced model of pulmonary fibrosis in rabbits

Aim:to perform a comparative analysis of the effi cacy of the inhaled and intravenous delivery of equivalent doses of bone marrow mesenchymal stem cells (BMMSCs) in rabbits according to the standard model of bleomycin pulmonary fi brosis.Materials and methods.After bronchoscopic instillation of bleomycin, 5 rabbits received intravenous transplantation of 2 × 106 allogeneic BMMSCs, other 5 rabbits – 2 × 107 MSCs inhaled via compressor nebulizer; control healthy and bleomycin group included 5 animals each.Results.Both groups treated with BMMSCs had a signifi cantly lower Ashcroft fi brosis index than the bleomycin control group. Expression of collagen in lung tissue in all groups with bleomycin injury was superior to healthy controls, but in animals underwent intravenous BMMSC transplantation collagen score was 0.74 points, and in inhaled treated group – 0.51 points, while in bleomycin controls – 2.1 point. Levels of TNF-α and TGF-β1 in BAL fl uids tended to decrease in treatment groups, but did not differ signifi cantly from control. A similar picture was observed in the cytological analysis of BAL.Conclusion.In general, both methods of delivering of BMMSCs to the lungs demonstrated similar therapeutic effects in inhibiting the development of experimental fi brosis, indicating that both intravenous and inhalational way of introduction can be used for subsequent clinical studies.

Intravenously Delivered Allogeneic Mesenchymal Stem Cells Bidirectionally Regulate Inflammation and Induce Neurotrophic Effects in Distal Middle Cerebral Artery Occlusion Rats Within the First 7 Days After Stroke

Background/Aims: Neurotrophic effects and immunosuppression are the main therapeutic mechanisms of mesenchymal stem cells (MSCs) in stroke treatment. Neurotrophins are produced by graft cells, host neurons, astrocytes, and even microglia/macrophages. Meanwhile, MSCs can increase inflammation if they are not sufficiently induced by pro-inflammatory cytokines. We examined whether intravenously transplanted bone marrow MSCs (BM-MSCs) increase inflammation in distal middle cerebral artery occlusion (dMCAO) rats, how long the increased inflammation effect persists for, and what the final therapeutic outcomes will be. We also tested the neurotrophic role of BM-MSCs and attempted to identify the neurotrophin-producing cells. Methods: At 1 h after dMCAO was performed on Sprague-Dawley rats, allogeneic BM-MSCs were transplanted intravenously. The infarct volume was examined by Tetrazolium Red staining at 2 days (day 2), and the behavioral tests (cylinder test and grid walking test) were performed at 2, 4 (day 4) and 7 days (day 7) after transplantation. The concentrations of inflammation related cytokines and neurotrophins in the ischemic cortex, ipsilateral striatum, and serum, were measured using ELISA at days 2-7. The cell source of neurotrophins was observed by immunohistochemistry. Results: The transplanted cells were mainly found in the infarct border zone (IBZ) of the brain. Infarct volume was reduced and behavioral outcomes were improved at 2 days after ischemia. In the striatum and circulation, BM-MSC transplantation increased inflammation at day 2 and decreased it at day 7. At days 2-7, insulin-like growth factor-1 (IGF-1) and brain-derived neurotrophic factor (BDNF) concentrations in the ischemic core of the cortex were significantly higher in the BM-MSC group than in the ischemia vehicle group. IGF-1 and BDNF were derived mainly from host microglia/macrophages in the ischemic core, and transplanted cells in the IBZ. At day 2, BM-MSC transplantation significantly increased the number of IGF-1⁺CD68⁺ and BDNF⁺Iba-1⁺ double positive cells in the ischemic core cortex. Conclusions: Although increased inflammation, BM-MSCs were still beneficial to dMCAO recovery at day 2. The immunopromoting effect of MSCs was transient and shifted to an immunosuppressive action at day 7. The neurotrophic factors IGF-1 and BDNF, which were mainly derived from transplanted BM-MSCs and host microglia/macrophages, contributed to the therapeutic effects from day 2 to day 7.

Coculture of allogenic DBM and BMSCs in the knee joint cavity of rabbits for cartilage tissue engineering.

The present study aims to assess coculture of allogenic decalcified bone matrix (DBM) and bone marrow mesenchymal stem cells (BMSCs) in the knee joint cavity of rabbits for cartilage tissue engineering. Rabbits were assigned to an in vitro group, an in vivo group, and a blank control group. At the 4th, 8th, and 12th week, samples from all groups were collected for hematoxylin–eosin (HE) staining and streptavidin–peroxidase (SP) method. The morphological analysis software was used to calculate the average absorbance value (A value). SP and flow cytometry demonstrated that BMSCs were induced into chondrocytes. DBM scaffold showed honeycomb-shaped porous and three-dimensional structure, while the surface pores are interlinked with the deep pores. At the 4th week, in the blank control group, DBM scaffold structure was clear, and cells analogous to chondrocytes were scattered in the interior of DBM scaffolds. At the 8th week, in the in vivo group, there were a large amount of cells, mainly mature chondrocytes, and the DBM scaffolds were partially absorbed. At the 12th week, in the in vitro group, the interior of scaffolds was filled up with chondrocytes with partial fibrosis, but arranged in disorder. In the in vivo group, the chondrocytes completely infiltrated into the interior of scaffolds and were arranged in certain stress direction. The in vivo group showed higher A value than the in vitro and blank control groups at each time point. Allogenic DBM combined BMSCs in the knee joint cavity of rabbits could provide better tissue-engineered cartilage than that cultivated in vitro.

RhBMP2-loaded calcium phosphate cements combined with allogenic bone marrow mesenchymal stem cells for bone formation

ObjectiveThe osteogenesis effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) and osteogenic differentiation potential of bone marrow mesenchymal stem cells (BMSCs) has been generally acknowledged. However, human bone formation effect of rhBMP-2 loaded calcium phosphate cememts (CPC) combined with allogenic BMSCs is still undefined. This study aimed to investigate how composite osteogenic bone marrow mesenchymal stem cells (BMSCs) and osteoinductive bone morphogenetic protein-2 (BMP-2) influenced the process of bone formation. MethodsWe chose calcium phosphate cements (cancellous bone granules; cancellous bone granules contained rhBMP-2) to facilitate osteogenesis. The composites of CPC+BMSC and CPC/rhBMP–2+BMSC were implanted respectively into nude mice via subcutaneous implantation and the tooth socket after maxillary canine teeth extraction. MAR analysis, Micro-CT analysis and immunohistochemistry assay were performed in this study to observe and compare by the schedule. ResultsIt was showed that combined with CPC+BMSC or CPC/rhBMP–2+BMSC induced stronger ability of the proliferation of allogenic BMSCs observed by scanning electron microscopy (SEM). Picric acid-fuchsin staining and immunohistochemical analysis illustrated the stronger new bone forming ability of CPC+BMSC group and CPC/rhBMP–2+BMSC group than those of controlled group. ConclusionThe combinations of rhBMP2-loaded CPC with allogeneic BMSCs promote new bone tissue formation.

Effect of Allogeneic Bone Marrow-mesenchymal Stem Cells (BM-MSCs) to Accelerate Burn Healing of Rat on the Expression of Collagen Type I and Integrin α2β1.

Burn is a public health problem, it causes physical disability even death. Treatment of burn wound has been conducted in various ways, but the satisfactory healing has not been provided. Bone marrow-derived mesenchymal stem cells (BM-MSCs) treatment is one of attempt to burn recovery, accelerate wound healing and angiogenesis. This study aimed to investigate the effect of allogeneic BM-MSC treatment on the expression of collagen type I and integrin α2β1 in burn skin tissue of rat observed on day 14. Twelve Wistar rats divided into two groups, control group (injected with phospate buffer solution) and treatment group (injected with BM-MSC). Rat was anaesthetized with xylazine and ketamine (ratio 1:1), fur of rat's back was shaved and full thickness burn was made by boiling plate in hot water for 30 min and patched on the back for 20 min. The burns were covered by tegaderm film and elastomult haft. Antalgin as an analgetic was injected to rats during observation process. Burns of rat was observed on day 14. In this study one-way analysis of variance test and Tukey as a further test were analyzed. The results showed that the healing time of allogeneic BM-MSC treatment on burn skin tissue rats was faster, the thickness of collagen type I in burn skin tissue of rats was thicker (0.977 μm) than controls (0.475 μm) and statistically demonstrated significant differences (p = 0.000). The average percentage of integrin α2β1 expression was higher (2.94%) than control group (2.34%), but the differences were not statistically significant (p = 0.176). The study concluded that BM-MSC treatment was able to accelerate the healing process of burns by increasing the thickness of the collagen and the percentage of integrin α2β1, thus accelerated the cell migration involved during wound healing.

Differentiation of Bone Marrow Mesenchymal Stem Cells in Osteoblasts and Adipocytes and its Role in Treatment of Osteoporosis.

Osteoporosis is a systemic metabolic bone disorder characterized by a decrease in bone mass and degradation of the bone microstructure, leaving bones that are fragile and prone to fracture. Most osteoporosis treatments improve symptoms, but to date there is no quick and effective therapy. Bone marrow mesenchymal stem cells (BMMSCs) have pluripotent potential. In adults, BMMSCs differentiate mainly into osteoblasts and adipocytes in the skeleton. However, if this differentiation is unbalanced, it may lead to a decrease in bone mass. If the number of adipocyte cells increases and that of osteoblast cells decreases, osteoporosis can result. A variety of hormones and cytokines play an important role in the regulation of BMMSCs bidirectional differentiation. Therefore, a greater understanding of the regulation mechanism of BMMSC differentiation may provide new methods to prevent and treat osteoporosis. In addition, autologous, allogeneic BMMSCs or genetically modified BMMSC transplantation can effectively increase bone mass and density, increase bone mechanical strength, correct the imbalance in bone metabolism, and increase bone formation, and is expected to provide a new strategy and method for the treatment of osteoporosis.

In Vivo Tracking of Systemically Administered Allogeneic Bone Marrow Mesenchymal Stem Cells in Normal Rats through Bioluminescence Imaging.

Recently, mesenchymal stem cells (MSCs) are increasingly used as a panacea for multiple types of disease short of effective treatment. Dozens of clinical trials published demonstrated strikingly positive therapeutic effects of MSCs. However, as a specific agent, little research has focused on the dynamic distribution of MSCs after in vivo administration. In this study, we track systemically transplanted allogeneic bone marrow mesenchymal stem cells (BMSCs) in normal rats through bioluminescence imaging (BLI) in real time. Ex vivo organ imaging, immunohistochemistry (IHC), and RT-PCR were conducted to verify the histological distribution of BMSCs. Our results showed that BMSCs home to the dorsal skin apart from the lungs and kidneys after tail vein injection and could not be detected 14 days later. Allogeneic BMSCs mainly appeared not at the parenchymatous organs but at the subepidermal connective tissue and adipose tissue in healthy rats. There were no significant MSCs-related adverse effects except for transient decrease in neutrophils. These findings will provide experimental evidences for a better understanding of the biocharacteristics of BMSCs.

HGF and IGF-1 promote protective effects of allogeneic BMSC transplantation in rabbit model of acute myocardial infarction.

To explore effects of hepatocyte growth factor (HGF) combined with insulin-like growth factor 1 (IGF-1) on transplanted bone marrow mesenchymal stem cells (BMSCs), for treatment of acute myocardial ischaemia. After ligation of the left anterior descending artery, rabbits were divided into a Control group, a Factors group (HGF+IGF-1), a BMSC group and a Factors+BMSCs group. Allogenous BMSCs (1 × 10(7)) and/or control-released microspheres of 2 μg HGF+2 μg IGF-1 were intramyocardially injected into infarcted regions. Apoptosis and differentiation of implanted BMSCs, histological and morphological results, and cardiac remodelling and function were evaluated at different time points. In vitro, BMSCs were exposed to HGF, IGF-1 and both (50 ng/ml) and subsequently proliferation, migration, myocardial differentiation and apoptosis induced by hypoxia, were analysed. Four weeks post-operatively, the above indices were significantly improved in Factors+BMSCs group compared to the others (P < 0.01), although Factors and BMSCs group also showed better results than Control group (P < 0.05). In vitro, HGF promoted BMSC migration and differentiation into cardiomyocytes, but inhibited proliferation (P < 0.05), while IGF-1 increased proliferation and migration, and inhibited apoptosis induced by hypoxia (P < 0.05), but did not induce myocardial differentiation. Combination of HGF and IGF-1 significantly promoted BMSCs capacity for migration, differentiation and lack of apoptosis (P < 0.05). Combination of HGF and IGF-1 activated BMSCs complementarily, and controlled release of the two factors promoted protective potential of transplanted BMSCs to repair infarcted myocardium. This suggests a new strategy for cell therapies to overcome acute ischemic myocardial injury.