Objective To explore the effect of the platelet-rich plasma (PRP) on proliferation and osteogenic differentiation of the bone marrow mesenchymal stem cells (MSCs) in China goat in vitro. Methods MSCs from the bone marrow of China goat were cultured. The third passage of MSCs were treated with PRP in the PRP group (the experimental group), but the cells were cultured with only the fetal calf serum (FCS) in the FCS group (the control group). The morphology and proliferation of the cells were observed by an inverted phase contrast microscope. The effect of PRP on proliferation of MSCs was examined by the MTT assay at 2,4,6 and 8 days. Furthermore, MSCs were cultured withdexamethasone（DEX）or PRP; alkaline phosphatase (ALP) and the calcium stainingwere used to evaluate the effect of DEX or PRP on osteogenic differatiation of MSCs at 18 days. The results from the PRP group were compared with those from the FCS group. Results The time for the MSCs confluence in the PRP group was earlier than that in the FCS group when observed under the inverted phase contrast microscope. The MTT assay showed that at 2, 4, 6 and 8 days the mean absorbance values were 0.252±0.026, 0.747±0.042, 1.173±0.067, and 1.242±0.056 in the PRP group, but 0.137±0.019, 0.436±0.052, 0.939±0.036, and 1.105±0.070 in the FCS group. The mean absorbance value was significantly higher in the PRP group than in the FCS group at each observation time (P＜0.01). Compared with the FCS group, the positive-ALP cells and the calcium deposition were decreased in the PRP group; however, DEX could increase boththe number of the positiveALP cells and the calcium deposition. Conclusion The PRP can promote proliferation of the MSCs of China goats in vitro but inhibit osteogenic differentiation.
Objective To study the mechanism of compound of calcium phosphate(TCP) and platelet-rich plasma(PRP) in the treatment of femoral head necrosis.Methods The left femoral heads of 48 New Zealand white rabbits were frozen by liquid nitrogen as to make themodel of femoral head necrosis.Twenty-four rabbits were randomly chosen as theexperimental group and their femoral heads were filled with TCP/PRP. The other 24 rabbits were used as the control group and their femoral heads were filled only with TCP. They were sacrificed at 2, 4,8,12 weeks after operation. The specimens were examined with X-ray and histological study.Results At 2 weeks after operation,there was no significant difference in femoral headdensity between the two groups. Four weeks after operation, femoral head density decreased in both groups, while it decreased more in the control group. At 8,12 weeks after operation, the density of the femoral heads in both groups increased, and it was higher in the experimental group. Histology examination showed thatthere was no difference between the two groups 2 weeks after operation. The head became flat at 4 weeks. Control group had more defects. At 4,8,12 weeks, more repairs were observed in the experimental group than that in the control group. The amount and maturity of osteogenesis in experimental group were much more greaterthan those in control group．Bone histomorphometry showed that the volum of thetrabecular was larger in the experimental group (36.65%±7.22%,38.29%±4.28%，39.24%±3.42%) than that of control group(P＜0.05). Conclusion TCP/PRP does not only provide osteoblasts scaffold, butalso promotes bone formation and the head repair. TCP/PRP is a good biomaterialfor the treatment of femur head necrosis.
OBJECTIVE: To study the effect of platelet-rich plasma in the repair of bone defect. METHODS: Segmental bone defects of 1 cm were created in the mid-upper part of bilateral radius of 24 New Zealand white rabbits. One side was randomly chosen as the experimental side, which was filled with artificial bone with platelet-rich plasma (PRP). The other side filled with artificial bone without PRP as the control. After 2, 4, 8 and 12 weeks of implantation, the gross, radiological, histological observations, and computer graphic analysis were performed to investigate the bone healing of the defect in both sides. RESULTS: Two weeks after operation, new bone and fibrous tissue formation in both the experimental and the control sides were observed only in the areas adjacent to the cut ends of the host bone, but the amount of new tissue in the experimental side was much more than that in the control side. In the 4th and 8th weeks, the surface of the artificial bone was covered with a large amount of new bones, the artificial bone was bridged tightly with the host bone by callus in the experimental side, while new bone was limited mainly in the cut ends and was less mature in the control side. In the 12th weeks, bone defects were entirely healed in the experimental side, which were covered completely with cortical bone, while new bone formation was only observed in the ends of artificial bone and there were not continuous bone callus on the surface in the control side. CONCLUSION: Artificial bone with PRP is effective in the repair of segmental bone defects, and PRP could improve the healing of bone defect.
ObjectiveTo identify a more popularized preparation protocol of leukocytes-rich platelet-rich plasma (L-PRP) for higher tolerance rate.MethodsThe peripheral blood samples of 76 volunteers (45.0 mL/case) were mixed with 5 mL sodium citrate injection for blood transfusion, and L-PRP was prepared by twice centrifugations. All blood samples were divided into three groups according to the parameters of twice centrifugation: experimental group A (12 cases, 400×g, 10 minutes for the first time and 1 100×g, 10 minutes for the second time), experimental group B (27 cases, 800×g, 10 minutes for the first time and 1 100×g, 10 minutes for the second time), and control group (37 cases, 1 360×g, 10 minutes for the first time and 1 360×g, 10 minutes for the second time). The platelet recovery rate and platelet and leukocyte enrichment coefficient of L-PRP in each group were calculated and compared.ResultsAfter removal of abnormal blood samples (platelet recovery rate was more than 100% or white thrombus), the remaining 55 cases were included in the statistical analysis, including 10 cases in experimental group A, 21 cases in experimental group B, and 24 cases in control group. The platelet enrichment coefficient and platelet recovery rate of experimental group B were significantly higher than those of experimental group A and control group (P<0.05); there was no significant difference between experimental group A and control group (P>0.05). There was no significant difference in leukocyte enrichment coefficient between experimental groups A, B, and control group (P>0.05).ConclusionThe preparation quality of PRP is affected by various factors, including centrifugal force, centrifugal time, temperature, and operation process, etc. Twice centrifugation (800×g, 10 minutes for the first time and 1 100×g, 10 minutes for the second time) is an ideal and feasible centrifugation scheme, which can obtain satisfactory platelet recovery rate and enrichment coefficient with thicker buffy coat, which can reduce the fine operation requirements for operators, improve the fault tolerance rate and generalization.
ObjectiveTo investigate the early effects of acellular xenogeneic nerve combined with adipose-derived stem cells (ADSCs) and platelet rich plasma (PRP) in repairing facial nerve injury in rabbits.MethodsThe bilateral sciatic nerves of 15 3-month-old male Sprague-Dawley rats were harvested and decellularized as xenografts. The allogeneic ADSCs were extracted from the neck and back fat pad of healthy adult New Zealand rabbits with a method of digestion by collagenase type Ⅰ and the autologous PRP was prepared by two step centrifugation. The 3rd generation ADSCs with good growth were labelled with CM-Dil living cell stain, and the labelling and fluorescence attenuation of the cells were observed by fluorescence microscope. Another 32 New Zealand rabbits were randomly divided into 4 groups and established the left facial nerve defect in length of 1 cm (n=8). The nerve defects of groups A, B, C, and D were repaired with CM-Dil-ADSCs composite xenogeneic nerve+autologous PRP, CM-Dil-ADSCs composite xenogeneic nerve, xenogeneic nerve, and autologous nerve, respectively. At 1 and 8 weeks after operation, the angle between the upper lip and the median line of the face (angle θ) was measured. At 4 and 8 weeks after operation, the nerve conduction velocity was recorded by electrophysiological examination. At 8 weeks after operation, the CM-Dil-ADSCs at the distal and proximal ends of regenerative nerve graft segment in groups A and B were observed by fluorescence microscopy; after toluidine blue staining, the number of myelinated nerve fibers in regenerated nerve was calculated; the structure of regenerated nerve fibers was observed by transmission electron microscope.ResultsADSCs labelled by CM-Dil showed that the labelling rate of cells was more than 90% under fluorescence microscope, and the labelled cells proliferated well, and the fluorescence attenuated slightly after passage. All the animals survived after operation, the incision healed well and no infection occurred. At 1 week after operation, all the animals in each group had different degrees of dysfunction. The angle θ of the left side in groups A, B, C, and D were (53.4±2.5), (54.0±2.6), (53.7±2.4), and (53.0±2.1)°, respectively; showing significant differences when compared with the healthy sides (P<0.05). At 8 weeks after operation, the angle θ of the left side in groups A, B, C, and D were (61.9±4.7), (56.8±4.2), (54.6±3.8), and (63.8±5.8)°, respectively; showing significant differences when compared with the healthy sides and with the values at 1 week (P<0.05). Gross observation showed that the integrity and continuity of regenerated nerve in 4 groups were good, and no neuroma and obvious enlargement was found. At 4 and 8 weeks after operation, the electrophysiological examination results showed that the nerve conduction velocity was significantly faster in groups A and D than in groups B and C (P<0.05), and in group B than in group C (P<0.05); no significant difference was found between groups A and D (P>0.05). At 8 weeks after operation, the fluorescence microscopy observation showed a large number of CM-Dil-ADSCs passing through the distal and proximal transplants in group A, and relatively few cells passing in group B. Toluidine blue staining showed that the density of myelinated nerve fibers in groups A and D were significantly higher than those in groups B and C (P<0.05), and in group B than in group C (P<0.05); no significant difference was found between groups A and D (P>0.05). Transmission electron microscope observation showed that the myelinated nerve sheath in group D was large in diameter and thickness in wall. The morphology of myelin sheath in group A was irregular and smaller than that in group D, and there was no significant difference between groups B and C.ConclusionADSCs can survive as a seed cell in vivo, and can be differentiated into Schwann-like cells under PRP induction. It can achieve better results when combined with acellular xenogeneic nerve to repair peripheral nerve injury in rabbits.
ObjectiveTo explore the clinical efficacy of the ultrasound-guided intra-articular injection of platelet-rich plasma (PRP) in the treatment of patients with different stages of knee osteoarthritis.MethodsWe retrospectively analyzed the clinical characteristics and X-ray data of patients with knee osteoarthritis who received ultrasound-guided intra-articular injection of PRP in the Department of Rehabilitation Medicine at Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University between May 2018 and June 2019. The patients were grouped according to the Kellgren & Lawrence Classification (K&L 0, Ⅰ, Ⅱ, Ⅲ, and Ⅳ). All the patients received four injections with a one-week interval. The Visual Analogue Scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were used to evaluate the clinical efficacy before the injection, and 3 and 6 months after the injection. Adverse reactions were recorded.ResultsA total of 102 patients were included without any grade 0 cases. There were 20 patients in K&L Ⅰ group, 37 in Ⅱ group, 31 in Ⅲ group, and 14 in Ⅳ group. No adverse event was reported. Significant differences of VAS scores and WOMAC index were observed in Ⅰ, Ⅱ and Ⅲ groups at the 3rd and 6th month follow-up (P<0.05). VAS and WOMAC scores of the three groups at the 3rd and 6th month after the treatment were significantly improved compared with those before the treatment (P<0.05). There was no significant difference in VAS score at the 3rd or 6th month after the treatment three groups (P>0.05). For K&L Ⅰ group, there was no statistically significant difference in WOMAC score at the 3rd or 6th month after the treatment (P>0.05). However, the WOMAC scores at the 3rd month after the treatment were better than those at the 6th month in K&L Ⅱ and Ⅲ groups (P<0.05). There was no significant time-depended changes in VAS score or WOMAC score in K&L Ⅳ group (P>0.05).ConclusionThe ultrasound-guided intra-articular PRP injection is safe and effective for pain relief and function improvement in patients with knee osteoarthritis at the early and middle stage.
Objective To calculate the recovery rate and enrichment factor and to analyse the correlation by measuring the concentrations of platelets, leukocyte, and growth factors in platelet-rich plasma (PRP) so as to evaluate the feasibil ity and stabil ity of a set of PRP preparation. Methods The peripheral blood (40 mL) was collected from 30 volunteers accorded with the inclusion criteria, and then 4 mL PRP was prepared using the package produced by Shandong Weigao Group Medical Polymer Company Limited. Automatic hematology analyzer was used to count the concentrations of platelets and leukocyte in whole blood and PRP. The enrichment factor and recovery rate of platelets or leukocyte were calculated; the platelet and leukocyte concentrations of male and female volunteers were measured, respectively. The concentrations of platelet-derived growth factor (PDGF), transforming growth factor β (TGF-β), and vascular endothel ial growth factor (VEGF) were assayed by ELISA. Results The platelet concentrations of whole blood and PRP were (131.40 ± 29.44) × 109/L and (819.47 ± 136.32) × 109/L, respectively, showing significant difference (t=—27.020, P=0.000). The recovery rate of platelets was 60.85% ± 8.97%, and the enrichment factor was 6.40 ± 1.06. The leukocyte concentrations of whole blood and PRP were (5.57 ± 1.91) × 1012/L and (32.20 ± 10.42) × 1012/L, respectively, showing significant difference (t=—13.780, P=0.000). The recovery rate of leukocyte was 58.30% ± 19.24%, and the enrichment factor was 6.10 ± 1.93. The concentrations of platelets and leukocyte in PRP were positively correlated with the platelet concentration (r=0.652, P=0.000) and leukocyte concentration (r=0.460, P=0.011) in whole blood. The concentrations of platelet and leukocyte in PRP between male and female were not significantly different (P gt; 0.05). The concentrations of PDGF, TGF-β, and VEGF in PRP were (698.15 ± 64.48), (681.36 ± 65.90), and (1 071.55 ± 106.04) ng/ mL,which were (5.67 ± 1.18), (6.99 ± 0.61), and (5.74 ± 0.83) times higher than those in the whole blood, respectively. PDGF concentration (r=0.832, P=0.020), TGF-β concentration (r=0.835, P=0.019), and VEGF concentration (r=0.824, P=0.023) in PRP were positively correlated with platelet concentration of PRP. Conclusion PRP with high concentrations of platelets, white blood cells and growth factors can be prepared stably by this package.