Bone regeneration in minipigs via calcium phosphate cement scaffold delivering autologous bone marrow mesenchymal stem cells and platelet‐rich plasma

Macroporous calcium phosphate cement (CPC) with stem cell seeding is promising for bone regeneration. The objective of this study was to investigate the effects of co‐delivering autologous bone marrow mesenchymal stem cells (BMSCs) and autologous platelet‐rich plasma (PRP) in CPC scaffold for bone regeneration in minipigs for the first time. Twelve female adult Tibet minipigs (12–18 months old) were used. A cylindrical defect with 10 mm height and 8 mm diameter was prepared at the femoral condyle. Two bone defects were created in each minipig, one at each side of the femoral condyle. Three constructs were tested: (1) CPC scaffold (CPC control); (2) CPC seeded with BMSCs (CPC‐BMSC); (3) CPC seeded with BMSCs and PRP (CPC‐BMSC‐PRP). Two time points were tested: 6 and 12 weeks (n = 4). Good integration of implant with surrounding tissues was observed in all groups. At 12 weeks, the CPC‐BMSC‐PRP group had significantly less residual CPC remaining in the defect than the CPC‐BMSC group and the CPC control (p < 0.05). The residual CPC volume for the CPC‐BMSC‐PRP group was half that of the CPC control. New bone formation for CPC‐BMSC‐PRP was more than two‐fold that of the CPC control (p < 0.05). CPC‐BMSC‐PRP had new blood vessel density that was nearly two‐fold that of the CPC control (p < 0.05). In conclusion, CPC scaffold with autologous BMSC‐PRP doubled the new bone regeneration and blood vessel density in minipigs compared with the CPC control. In the present study, the new macroporous CPC system with co‐delivered BMSC‐PRP has been shown to promote scaffold resorption and bone regeneration in large defects. Copyright © 2017 John Wiley & Sons, Ltd.     

A rapid method for obtaining mesenchymal stem cells and platelets from bone marrow aspirate

Mesenchymal stem cells (MSCs) and platelet‐rich plasma (PRP) are currently used alone or in combination for therapeutic applications especially for bone repair. We tested whether MSCs can be isolated from bone marrow (BM) aspirate using a commercially available kit commonly used to obtain PRP from peripheral blood (PB). Results revealed that mononuclear cells and platelets from both PB and BM could be efficiently isolated by obtaining a mononuclear and platelet rich fraction (PB‐MPRF and BM‐MPRF, respectively). Starting with comparable volumes, the number of platelets increased 1.5‐fold in BM‐MPRF compared to PB‐MPRF. The number of clonogenic cells in BM‐MPRF samples was significantly higher than whole BM samples as revealed by CFU‐F assay (54.92 ± 8.55 CFU‐F/1.5 x 10⁵ nucleated cells and 32.50 ± 12.43 CFU‐F/1.5 x 10⁵ nucleated cells, respectively). Cells isolated from BM‐MPRF after in vitro expansion fulfilled the definition of MSCs by phenotypic criteria, and differentiated along osteogenic, adipogenic and chondrogenic lineages following induction. Results showed that the kit isolated MSCs and platelets from BM aspirate. Isolated MSCs were further expanded in a laboratory and BM‐MPRF was used clinically following BM withdrawal for rapid intra‐operative cell therapy for the treatment of bone defects. Copyright © 2012 John Wiley & Sons, Ltd.     

Combination of platelet‐rich plasma within periodontal ligament stem cell sheets enhances cell differentiation and matrix production

The longstanding goal of periodontal therapy is to regenerate periodontal tissues. Although platelet‐rich plasma (PRP) has been gaining increasing popularity for use in the orofacial region, whether PRP is useful for periodontal regeneration is still unknown. The purpose of this study was to determine whether a mixture of periodontal ligament stem cell (PDLSC) sheets and PRP promoted bone regeneration, one of the most important measurement indices of periodontal tissue regenerative capability in vitro and in vivo. In this study, we evaluated the effects of different doses of PRP on the differentiation of human PDLSCs. Then cell sheet formation, extracellular matrix deposition and osteogenic gene expression in response to different doses of PRP treatment during sheet grafting was investigated. Furthermore, we implanted PDLSC sheets treated with 1% PRP subcutaneously into immunocompromised mice to evaluate their bone‐regenerative capability. The results revealed that 1% PRP significantly enhanced the osteogenic differentiation of PDLSCs. Based on the production of extracellular matrix proteins, the results of scanning electron microscopy and the expression of the osteogenic genes ALP, Runx2, Col‐1 and OCN, the provision of 1% PRP for PDLSC sheets was the most effective PRP administration mode for cell sheet formation. The results of in vivo transplantation showed that 1% PRP‐mediated PDLSC sheets exhibited better periodontal tissue regenerative capability than those obtained without PRP intervention. These data suggest that a suitable concentration of PRP stimulation may enhance extracellular matrix production and positively affect cell behaviour in PDLSC sheets. Copyright © 2014 John Wiley & Sons, Ltd.     

Activated platelet‐rich plasma improves cartilage regeneration using adipose stem cells encapsulated in a 3D alginate scaffold

In the current study, the effect of superimposing platelet‐rich plasma (PRP) on different culture mediums in a three‐dimensional alginate scaffold encapsulated with adipose‐derived mesenchymal stem cells for cartilage tissue repair is reported. The three‐dimensional alginate scaffolds with co‐administration of PRP and/or chondrogenic supplements had a significant effect on the differentiation of adipose mesenchymal stem cells into mature cartilage, as assessed by an evaluation of the expression of cartilage‐related markers of Sox9, collagen II, aggrecan and collagen, and glycosaminoglycan assays. For in vivo studies, following induction of osteochondral lesion in a rabbit model, a high degree of tissue regeneration in the alginate plus cell group (treated with PRP plus chondrogenic medium) compared with other groups of cell‐free alginate and untreated groups (control) were observed. After 8 weeks, in the alginate plus cell group, functional chondrocytes were observed, which produced immature matrix, and by 16 weeks, the matrix and hyaline‐like cartilage became completely homogeneous and integrated with the natural surrounding cartilage in the defect site. Similar effect was also observed in the subchondral bone. The cell‐free scaffolds formed fibrocartilage tissue, and the untreated group did not form a continuous cartilage over the defect by 16 weeks.     

Combined treatment with platelet‐rich plasma and insulin favours chondrogenic and osteogenic differentiation of human adipose‐derived stem cells in three‐dimensional collagen scaffolds

Osteochondral lesions due to injury or other pathology commonly result in the development of osteoarthritis and progressive joint destruction. Bioengineered scaffolds are widely studied for regenerative surgery strategies in osteochondral defect management, also combining the use of stem cells, growth factors and hormones. The utility in tissue engineering of human adipose‐derived stem cells (ASCs) isolated from adipose tissue has been widely noted. Autologous platelet‐rich plasma (PRP) represents an alternative strategy in regenerative medicine for the local release of endogenous growth factors and hormones. Here we compared the effects of three‐dimensional (3D) collagen type I scaffold culture and combined treatment with PRP and human recombinant insulin on the chondro‐/osteogenic differentiation of ASCs. Histochemical and biomolecular analyses demonstrated that chondro‐/osteogenic differentiation was increased in ASC‐populated 3D collagen scaffolds compared with two‐dimensional (2D) plastic dish culture. Chondro‐/osteogenic differentiation was further enhanced in the presence of combined PRP (5% v/v) and insulin (100 nm ) treatment. In addition, chondro‐/osteogenic differentiation associated with the contraction of ASC‐populated 3D collagen scaffold and increased β1/β3‐integrin expression. Inhibition studies demonstrated that PRP/insulin‐induced chondro‐/osteogenic differentiation is independent of insulin‐like growth factor 1 receptor (IGF‐1R) and mammalian target of rapamycin (mTOR) signalling; IGF‐R1/mTOR inhibition even enhanced ASC chondro‐/osteogenic differentiation. Our findings underline that 3D collagen scaffold culture in association with platelet‐derived growth factors and insulin favour the chondro‐/osteogenic differentiation of ASCs, suggesting new translational applications in regenerative medicine for the management of osteochondral defects. Copyright © 2016 John Wiley & Sons, Ltd.     

Effective expansion of human adipose‐derived stromal cells and bone marrow‐derived mesenchymal stem cells cultured on a fragmin/protamine nanoparticles‐coated substratum with human platelet‐rich plasma

Fragmin/protamine nanoparticles (F/P NPs) can be stably coated onto plastic surfaces and used as a substratum for the absorption and controlled release of growth factors (GFs) secreted from human platelet‐rich plasma (PRP). In this study, we investigated the capability of F/P NP‐coated plates to act as a substratum for the proliferation of human adipose‐derived stromal cells (ASCs) and bone marrow‐derived mesenchymal stem cells (BMSCs) with GFs in PRP. Both cell types adhered well to the F/P NP‐coated plates and grew optimally, with a doubling time of 30 and 32 h in low‐concentration PRP (0.5%) medium supplemented with 5 ng/ml fibroblast growth factor‐2 (FGF‐2) on the F/P NP‐coated plates. These cells maintained their multilineage potential for differentiation into adipocytes or osteoblasts. Furthermore, ASCs and BMSCs grew well in medium without PRP and FGF‐2 on F/P NP‐coated plates pretreated with PRP and FGF‐2 in a concentration‐dependent manner. Thus, F/P NP‐coated plates are a useful substratum for the adherence and proliferation of ASCs and BMSCs in low‐concentration PRP medium supplemented with FGF‐2. No xenogeneic serum is required. Copyright © 2012 John Wiley & Sons, Ltd.     

骨髓间充质干细胞促进胰岛再生的作用与研究现状

背景：研究发现,骨髓间充质干细胞移植入糖尿病大鼠后能够降低其血糖。目的：综述骨髓间充质干细胞在促进胰岛再生方面的作用与研究现状。方法：应用计算机检索2003年7月至2011年12月PubMed数据库相关文章,检索词为＂bone marrow derive mesenchymal stem cell,islet cells＂,并限定文章语言种类为English。同时计算机检索2003年7月至2011年12月万方数据库相关文章,检索词为＂骨髓间充质干细胞,胰岛细胞＂,并限定文章语言种类为中文。最终纳入符合标准的文献25篇。结果与结论：目前,移植胰岛治疗糖尿病已取得良好疗效,但由于胰岛来源匮乏和异种或异体来源的胰岛引起免疫排斥反应而难以使众多糖尿患者受益。骨髓间充质干细胞取材方便,容易进行体外分离、培养和纯化,且具有多向分化潜能。若将骨髓间充质干细胞诱导分化为胰岛细胞,可望解决胰岛细胞来源和免疫排斥问题。文章对骨髓间充质干细胞分化为胰岛细胞治疗糖尿病的研究进展进行综述,并指出了存在问题和今后的研究方向。     

Platelet‐rich plasma counteracts detrimental effect of high‐glucose concentrations on mesenchymal stem cells from Bichat fat pad

Diabetic patients display increased risk of periodontitis and failure in bone augmentation procedures. Mesenchymal stem cells (MSCs) and platelet‐rich plasma (PRP) represent a relevant advantage in tissue repair process and regenerative medicine. We isolated MSCs from Bichat's buccal fat pad (BFP) and measured the effects of glucose and PRP on cell number and osteogenic differentiation potential. Cells were cultured in the presence of 5.5‐mM glucose (low glucose [LG]) or 25‐mM glucose (high glucose [HG]). BFP–MSC number was significantly lower when cells were cultured in HG compared with those in LG. Following osteogenic differentiation procedures, calcium accumulation, alkaline phosphatase activity, and expression of osteogenic markers were significantly lower in HG compared with LG. Exposure of BFP–MSC to PRP significantly increased cell number and osteogenic differentiation potential, reaching comparable levels in LG and in HG. Thus, high‐glucose concentrations impair BFP–MSC growth and osteogenic differentiation. However, these detrimental effects are largely counteracted by PRP.     

Increased survival of human free fat grafts with varying densities of human adipose‐derived stem cells and platelet‐rich plasma

The high absorption rate of transplanted fat has limited the application of autogenous fat grafts in the clinical setting. Therefore, this study aimed to evaluate the effects of platelet‐rich plasma (PRP) and adipose‐derived stem cells (ASCs) on fat regeneration by investigating the impact of PRP and conditioned medium on the biological characteristics of ASCs. Fat grafts were prepared with ASCs at densities of 10⁷/ml, 10⁶/ml, 10⁵/ml, 10⁴/ml and 0/ml with and without PRP and injected subcutaneously into nude mice. Liquid overflow method, haematoxylin and eosin staining, and immunohistochemical analyses were used to examine the fat grafts. The residual fat volume of the 10⁵/ml ASC + PRP group was significantly higher than that of other treatment conditions after 90 days. Furthermore, histological examination revealed that in 10⁵/ml ASCs‐treated grafts normal adipocyte area and capillary formation were increased dramatically compared with other treatment conditions. It is concluded that fat grafts consisting of PRP and 10⁵/ml ASCs constitute an ideal transplant strategy, which may result in decreased absorption and accelerated fat regeneration. This simple and reliable method could provide a valuable and needed tool in plastic and reconstructive surgery. Copyright © 2014 John Wiley & Sons, Ltd.     

柚皮甙诱导兔骨髓间充质干细胞的成骨特征

背景：骨碎补能在促进骨生长且取得了良好的临床疗效,其主要成分柚皮甙能否诱导骨髓间充质干细胞向成骨方向分化？目的：用柚皮甙诱导兔骨髓间充质干细胞向成骨方向分化。并观察柚皮甙诱导兔骨髓间充质干细胞向成骨方向分化的能力。方法：用贴壁筛选法对兔骨髓间充质干细胞进行分离培养。对生长良好的第3代骨髓间充质干细胞分别用50μg／L的柚皮甙和经典成骨诱导剂向成骨方向进行诱导,分别进行成骨鉴定。结果与结论：经典成骨诱导液、柚皮甙诱导液都能使骨髓间充质干细胞向成骨方向分化,基质分泌增多,形成钙结节。用酶联免疫检测仪检测柚皮甙诱导组和经典成骨诱导组细胞吸光度值未见明显的差异。同时检测柚皮甙诱导液和L—DMEN细胞培养液的吸光度值发现两者差异无显著性意义（P〉0．05）。证实柚皮甙可成功诱导骨髓间充质干细胞向成骨方向分化,无明显毒性作用。     

Bio-Gide胶原膜对兔骨髓间充质干细胞增殖和成骨分化的影响

背景：相关实验表明Bio-Gide胶原膜与细胞有良好的生物相容性,但有关与其复合培养干细胞成骨分化能力的报道少见。 目的：观察Bio-Gide胶原膜对骨髓间充质干细胞增殖及成骨分化的影响。 方法：全骨髓贴壁法体外分离培养兔骨髓间充质干细胞,将第3代兔骨髓间充质干细胞分别接种于覆盖Bio—Gide胶原膜的培养板（实验组）与单纯培养板（对照组）培养。于培养1,4,7,14d利用CCK-8试剂盒检测细胞增殖;成骨分化诱导培养1,4,7,14d收集细胞培养液上清,检测细胞碱性磷酸酶活性。 结果与结论：两组细胞数量均随着培养时间的增加而不断增加,对照组培养7d细胞数量明显多于实验组（P〈0．05）,其他时间点组间比较差异无显著性意义。两组细胞碱性磷酸酶活性均随着培养时间的增加而不断增加,实验组成骨诱导14d细胞碱性磷酸酶活性高于对照组（P〈0．05）,其他时间点组间比较差异无显著性意义。表明Bio-Gide胶原膜可促进兔骨髓间充质干细胞的增殖及成骨分化。     

Persistence of fluorescent nanoparticle‐labelled bone marrow mesenchymal stem cells in vitro and after intra‐articular injection

Mesenchymal stem cells (MSCs) improve the osteoarthritis condition, but the fate of MSCs after intra‐articular injection is unclear. We used fluorescent nanoparticles (quantum dots [QDs]) to track equine MSCs (QD‐labelled MSCs [QD‐MSCs]) in vivo after intra‐articular injection into normal and osteoarthritic joints. One week after injection of QD‐MSCs, unlabelled MSCs, or vehicle, we determined the presence of QD‐MSCs in synovium and articular cartilage histologically. In vitro, we evaluated the persistence of QDs in MSCs and whether QDs affected proliferation, immunophenotype, or differentiation. In joints injected with QD‐MSCs, labelled cells were identified on the synovial membrane and significantly less often on articular cartilage, without differences between normal and osteoarthritic joints. Joints injected with QD‐MSCs and MSCs had increased synovial total nucleated cell count and protein compared with vehicle‐injected joints. In vitro, QDs persisted in nonproliferating cells for up to 8 weeks (length of the study), but QD fluorescence was essentially absent from proliferating cells within two passages (approximately 3 to 5 days). QD labelling did not affect MSC differentiation into chondrocytes, adipocytes, and osteocytes. QD‐MSCs had slightly different immunophenotype from control cells, but whether this was due to an effect of the QDs or to drift during culture is unknown. QD‐MSCs can be visualized in histological sections 1 week after intra‐articular injection and are more frequently found in the synovial membrane versus cartilage in both normal and osteoarthritic joints. QDs do not alter MSC viability and differentiation potential in vitro. However, QDs are not optimal markers for long‐term tracking of MSCs, especially under proliferative conditions.     

Evaluation of platelet‐rich plasma and hydrostatic pressure regarding cell differentiation in nucleus pulposus tissue engineering

Generation of a biological nucleus pulposus (NP) replacement by tissue engineering appears to be a promising approach for the therapy of early stages of intervertebral disc degeneration. Thereby, autologous mesenchymal stem cells (MSCs) represent an attractive cell source compared to cells of the NP that are already altered in their phenotype due to degenerative processes. This study compares the influence of 3D pellet culture and alginate beads, as well as that of different media compositions, by the addition of human platelet‐rich plasma (PRP) or transforming growth factor (TGF‐β₁) in interaction with hydrostatic pressure on chondrogenic differentiation of human MSCs compared to NP cells. We found that gene expression of the chondrogenic markers aggrecan, collagen type 2 and collagen type 1 and Sox9 was considerably lower in cells cultivated with PRP compared to TGF‐β₁. Immunohistology confirmed this result at protein level in pellet culture. Additionally, the pellet culture system was found to be more suitable than alginate beads. A positive influence of hydrostatic pressure could only be shown for individual donors. In summary, in comparison to TGF‐β₁, human PRP did not induce adequate chondrogenic differentiation for both culture systems and cell types used. The mixture of growth factors in PRP promoted proliferation rather than chondrogenic differentiation. Based on these results, an application of PRP in human NP tissue‐engineering approaches cannot be recommended. Copyright © 2011 John Wiley & Sons, Ltd.     

Effect of biomimetic zinc‐containing tricalcium phosphate (Zn–TCP) on the growth and osteogenic differentiation of mesenchymal stem cells

Several studies have shown the effectiveness of zinc‐tricalcium phosphate (Zn–TCP) for bone tissue engineering. In this study, marine calcareous foraminifera possessing uniform pore size distribution were hydrothermally converted to Zn–TCP. The ability of a scaffold to combine effectively with mesenchymal stem cells (MSCs) is a key tissue‐engineering aim. In order to demonstrate the osteogenic ability of MSCs with Zn–TCP, the scaffolds were cultured in an osteogenic induction medium to elicit an osteoblastic response. The physicochemical properties of Zn–TCP were characterized by XRD, FT–IR and ICP–MS. MSCs were aspirated from rat femurs and cultured for 3 days before indirectly placing four samples into each respective well. After culture for 7, 10 and 14 days, osteoblastic differentiation was evaluated using alizarin red S stain, measurement of alkaline phosphatase (ALP) levels, cell numbers and cell viability. XRD and FT–IR patterns both showed the replacement of CO₃^2– with PO₄^3–. Chemical analysis showed zinc incorporation of 5 mol%. Significant increases in cell numbers were observed at 10 and 14 days in the Zn–TCP group, while maintaining high levels of cell viability (> 90%). ALP activity in the Zn–TCP group was statistically higher at 10 days. Alizarin red S staining also showed significantly higher levels of calcium mineralization in Zn–TCP compared with the control groups. This study showed that MSCs in the presence of biomimetically derived Zn–TCP can accelerate their differentiation to osteoblasts and could potentially be useful as a scaffold for bone tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd.     

Cell bricks‐enriched platelet‐rich plasma gel for injectable cartilage engineering – an in vivo experiment in nude mice

Clinical application of platelet‐rich plasma (PRP)‐based injectable tissue engineering is limited by weak mechanical properties and a rapid fibrinolytic rate. We proposed a new strategy, a cell bricks‐stabilized PRP injectable system, to engineer and regenerate cartilage with stable morphology and structure in vivo. Chondrocytes from the auricular cartilage of rabbits were isolated and cultured to form cell bricks (fragmented cell sheet) or cell expansions. Fifteen nude mice were divided evenly (n = 5) into cells–PRP (C‐P), cell bricks–PRP (CB‐P) and cell bricks–cells–PRP (CB‐C‐P) groups. Cells, cell bricks or a cell bricks/cells mixture were suspended in PRP and were injected subcutaneously in animals. After 8 weeks, all the constructs were replaced by white resilient tissue; however, specimens from the CB‐P and CB‐C‐P groups were well maintained in shape, while the C‐P group appeared distorted, with a compressed outline. Histologically, all groups presented lacuna‐like structures, glycosaminoglycan‐enriched matrices and positive immunostaining of collagen type II. Different from the uniform structure presented in CB‐C‐P samples, CB‐P presented interrupted, island‐like chondrogenesis and contracted structure; fibrous interruption was shown in the C‐P group. The highest percentage of matrix was presented in CB‐C‐P samples. Collagen and sGAG quantification confirmed that the CB‐C‐P constructs had statistically higher amounts than the C‐P and CB‐P groups; statistical differences were also found among the groups in terms of biomechanical properties and gene expression. We concluded that cell bricks‐enriched PRP gel sufficiently enhanced the morphological stability of the constructs, maintained chondrocyte phenotypes and favoured chondrogenesis in vivo, which suggests that such an injectable, completely biological system is a suitable cell carrier for cell‐based cartilage repair. Copyright © 2012 John Wiley & Sons, Ltd.     

髓核细胞诱导骨髓间充质干细胞向髓核方向的分化

背景：国内外已有很多文献相继报道了用骨髓间充质干细胞-藻酸盐复合植入材料来修复大鼠退变的腰椎间盘,但尚缺少对此复合物与正常髓核细胞之间的各项生物学指标的比较。目的：在Transwell非接触共培养条件下,研究髓核细胞对骨髓间充质干细胞的诱导作用。方法：全骨髓法培养大鼠骨髓间充质干细胞并鉴定,取第3代骨髓间充质干细胞及髓核细胞复合藻酸盐接种于Transwell共培养系统中,上室接种骨髓间充质干细胞藻酸盐复合物,下室接种髓核细胞藻酸盐复合物,共培养7d后回收上层骨髓间充质干细胞。结果与结论：RT-PCR方法检测共培养组Ⅱ型胶原、Sox-9和多功能蛋白聚糖的mRNA表达均接近正常髓核细胞。说明共培养条件下髓核细胞能诱导骨髓间充质干细胞向髓核方向分化。     

Dermal matrix scaffold engineered with adult mesenchymal stem cells and platelet-rich plasma as a potential tool for tissue repair and regeneration

The purpose of this study was to investigate the efficacy of Integra, an artificial dermal matrix used as a dermal template for skin regeneration, to form a multifunctional scaffold with human bone marrow-derived mesenchymal stem cells (hMSCs) and platelet-rich plasma (PRP) for tissue engineering and regenerative technology. First, we showed that PRP, used as a supplement for growth medium, represented an optimal substitute for animal serum as well as a source of multiple growth factors, was able to satisfactorily support cell viability and cell proliferation and influence stemness gene expression in hMSCs. Moreover, Integra appeared to be a suitable substrate for hMSCs colonization, as judged by two-photon microscopy combined with fluorescence lifetime imaging (FLIM) and confocal analysis. The cells were then seeded on Integra + PRP for 24 and 48 h. Notably, in these conditions, the seeded cells exhibited a greater aptitude to colonize the scaffold, showed improved cell adhesion and spreading as compared with those cultured on Integra alone, and acquired a fibroblast-like phenotype, indicating that the bioengineered scaffold provided an appropriate environment for cellular growth and differentiation. In conclusion, these results, although preliminary, provide clues for the design of new therapeutic strategies for skin regeneration, consisting in the combination of mesenchymal stem cells with engineered biomaterials.     

自体激活富血小板血浆干预兔骨髓间充质干细胞体外成软骨分化的研究

背景：自体富血小板血浆激活后可释放多种生长因子,可以促进骨髓间充质干细胞的增殖与分化。目的：观察自体激活富血小板血浆对体外培养的兔骨髓间充质干细胞向成软骨细胞分化的影响。方法：取兔股骨骨髓,全骨髓贴壁法分离培养骨髓间充质干细胞;取第3代骨髓间充质干细胞,分别应用体积分数10%自体激活富血小板血浆和体积分数10%胎牛血清培养液进行体外培养,观察其向成软骨细胞分化情况。结果与结论：分离培养的兔骨髓间充质干细胞呈长梭形,传代后细胞生长迅速。流式细胞仪检测发现第3代细胞高表达CD29、CD44,而低表达CD45。免疫荧光细胞化学染色显示经自体激活富血小板血浆诱导的骨髓间充质干细胞表达Ⅱ型胶原;实时荧光定量PCR检测发现经自体激活富血小板血浆诱导的骨髓间充质干细胞Ⅱ型胶原α1链基因和聚集蛋白聚糖基因表达明显高于经胎牛血清诱导的骨髓间充质干细胞（P〈0.01）。可见自体激活富血小板血浆具有促进兔骨髓间充质干细胞向软骨细胞方向分化的潜能。     

Allogeneic platelet‐rich plasma affects monocyte differentiation to dendritic cells causing an anti‐inflammatory microenvironment,putatively fostering wound healing

Autologous platelet‐rich plasma (PRP) is used clinically to induce repair of different tissues through the release of bioactive molecules. In some patients, the production of efficient autologous PRP is unfeasible due to their compromised health. Allogeneic PRP mismatched for AB0 and Rh antigens was developed. The effect of allogeneic PRP on immune response should be defined to use it in clinical practice avoiding side effects. Thus, whether PRP affects the differentiation of peripheral blood monocytes to dendritic cells upon stimulation with granulocyte monocyte colony stimulating factor and interleukin‐4 was investigated. Indeed, these cells are the main players of immune response and tissue repair. PRP inhibited the differentiation of monocytes to CD1a⁺ dendritic cells and favoured the expansion of phagocytic CD163⁺CD206⁺ fibrocyte‐like cells. These cells produced interleukin‐10 and prostaglandin‐E₂, but not interferon‐γ, upon stimulation with lipopolysaccharides. Moreover, they promoted the expansion of regulatory CD4⁺CD25⁺FoxP3⁺ T cells upon allostimulation or antigen specific priming. Finally, the conditioned medium harvested from monocytes differentiated with PRP triggered a strong chemotactic effect on mesenchymal cells in both scratch and transwell migration assays. These results strongly suggest that allogeneic PRP can foster the differentiation of monocytes to a regulatory anti‐inflammatory population, possibly favouring wound healing. Copyright © 2016 John Wiley & Sons, Ltd.