Platelet-Rich Fibrin in Fat Grafts for Facial Lipofilling: A Randomized, Controlled Split-Face Clinical Trial.

Objective: Previous studies have reported that platelet-rich fibrin (PRF) may enhance the efficacy of fat grafts in facial lipofilling. However, these studies either lacked objective data or were not randomized, controlled trials. Thus, we aimed to objectively evaluate the efficacy of PRF in facial lipofilling. Methods: A controlled, split-face, randomized trial (January 2018 to May 2019) based on 18 patients who underwent fat grafts for bilateral temple lipofilling was performed. Each patient received a combination of an autologous fat graft and PRF on one side and a fat graft combined with an equal volume of saline on the other side. The effects of PRF were evaluated by comparing the remaining bilateral fat graft volumes through a digital three-dimensional reconstruction technique. Improvements in the appearance and recovery time of each temple were assessed by both a surgeon and patients who were blinded to the treatment assignment. Complications were also recorded. Results: Bilateral temple lipofilling showed no evidence of fat embolism, vascular/nerve injury, infection, massive edema, or prolonged bruising. Three-dimensional reconstruction data and the assessments from both the surgeon and patients revealed no significant differences in fat graft retention volume between the PRF-positive and PRF-negative lipofilling groups. However, recovery time in the PRF-positive lipofilling sites was significantly shortened compared with that of the PRF-negative lipofilling sites. Conclusion: Facial filling with autologous fat grafts is effective and safe. Our results show that PRF does not markedly improve fat graft volume retention in the temple but significantly reduces postoperative recovery time. Trial Registration Number: ChiCTR2100053663.

Decellularized adipose matrix provides an inductive microenvironment for stem cells in tissue regeneration.

Stem cells play a key role in tissue regeneration due to their self-renewal and multidirectional differentiation, which are continuously regulated by signals from the extracellular matrix (ECM) microenvironment. Therefore, the unique biological and physical characteristics of the ECM are important determinants of stem cell behavior. Although the acellular ECM of specific tissues and organs (such as the skin, heart, cartilage, and lung) can mimic the natural microenvironment required for stem cell differentiation, the lack of donor sources restricts their development. With the rapid development of adipose tissue engineering, decellularized adipose matrix (DAM) has attracted much attention due to its wide range of sources and good regeneration capacity. Protocols for DAM preparation involve various physical, chemical, and biological methods. Different combinations of these methods may have different impacts on the structure and composition of DAM, which in turn interfere with the growth and differentiation of stem cells. This is a narrative review about DAM. We summarize the methods for decellularizing and sterilizing adipose tissue, and the impact of these methods on the biological and physical properties of DAM. In addition, we also analyze the application of different forms of DAM with or without stem cells in tissue regeneration (such as adipose tissue), repair (such as wounds, cartilage, bone, and nerves), in vitro bionic systems, clinical trials, and other disease research.

Transconjunctival Orbital Septum Fat Release and Preservation for Orbitopalpebral Sulcus in Lower Eyelid Blepharoplasty.

BACKGROUND: Compared to the traditional transcutaneous approach, a safe and effective lower eyelid blepharoplasty has been recognized. In 2007, Sadove first reported a series of patients treated with transconjunctival septal suturing, but the inferior orbitopalpebral sulcus was not totally improved. PURPOSE: Orbital septal fat release and preservation through the transconjunctival approach was used to treat 20 young patients with bulging bags and inferior orbitopalpebral sulcus. METHOD: The orbital septal fat was released and transferred to infraorbital rim to be a base for the inferior orbitopalpebral sulcus. RESULT: Obvious bulging fat was released, and the orbitopalpebral sulcus was flattened by released and excessive orbital septal fat. Satisfactory results were achieved. CONCLUSION: The results achieved from this series of patients indicate that orbital septal fat release and preservation through the transconjunctival approach for reducing the orbitopalpebral sulcus is a safe and effective treatment for bulging fat and orbitopalpebral sulcus in young patients. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Inhibition of both EGFR and IGF1R sensitized prostate cancer cells to radiation by synergistic suppression of DNA homologous recombination repair.

Reduced sensitivity of prostate cancer (PC) cells to radiation therapy poses a significant challenge in the clinic. Activation of epidermal growth factor receptor (EGFR), type 1 insulin-like growth factor receptor (IGF1R), and crosstalk between these two signaling pathways have been implicated in the development of radiation resistance in PC. This study assessed the effects of targeting both receptors on the regulation of radio-sensitivity in PC cells. Specific inhibitors of EGFR and IGF1R, Erlotinib and AG1024, as well as siRNA targeting EGFR and IGF1R, were used to radio-sensitize PC cells. Our results showed that co-inhibiting both receptors significantly dampened cellular growth and DNA damage repair, and increased radio-sensitivity in PC cells. These effects were carried out through synergistic inhibition of homologous recombination-directed DNA repair (HRR), but not via inhibition of non-homologous end joining (NHEJ). Furthermore, the compromised HRR capacity was caused by reduced phosphorylation of insulin receptor substrate 1 (IRS1) and its subsequent interaction with Rad51. The synergistic effect of the EGFR and IGF1R inhibitors was also confirmed in nude mouse xenograft assay. This is the first study testing co-inhibiting EGFR and IGF1R signaling in the context of radio-sensitivity in PC and it may provide a promising adjuvant therapeutic approach to improve the outcome of PC patients to radiation treatment.

Histone deacetylase inhibitor reduces hypertrophic scarring in a rabbit ear model.

BACKGROUND: Hypertrophic scars result from excessive collagen deposition at sites of healing dermal wounds and could be functionally and cosmetically problematic. The authors tested the ability of the histone deacetylase inhibitor trichostatin A to reduce hypertrophic scar formation in a rabbit ear model. METHODS: The authors have developed a reliable rabbit model that results in hypertrophic scarring. Four 1-cm, full-thickness, circular wounds were made on each ear. After the wounds reepithelialized, 0.02% trichostatin A was injected intradermally into the wounds in the treatment group. Expression of collagen I and fibronectin was detected by reverse transcription polymerase chain reaction and Western blot analysis at postoperative day 23. Scar hypertrophy was quantified by measurement of the scar elevation index at postoperative day 45. RESULTS: Compared with the control group, injection of trichostatin A led to much more normal-appearing scars in the rabbit ear. The scar elevation index at postoperative day 45 was significantly decreased after injection of trichostatin A compared with untreated scars. Furthermore, the authors confirmed the decreased expression of collagen I and fibronectin at postoperative day 23 (after the rabbits had been treated with trichostatin A for 1 week) in the treated scars compared with the control scars according to reverse transcription polymerase chain reaction and Western blot analysis. CONCLUSIONS: The introduction of trichostatin A can result in the decreased formation of hypertrophic scars in a rabbit ear model, which is corroborated by evidence of decreased collagen I and fibronectin synthesis.

Trichostatin A inhibits collagen synthesis and induces apoptosis in keloid fibroblasts.

Keloid, a fibro-proliferative benign tumor of skin, is characterized by an enriched milieu of growth factors and an abundant accumulation of extracellular matrix (ECM). Transforming growth factor (TGF)-ß1 is well known as the crucial fibrogenic cytokine promoting ECM production and tissue fibrosis in keloid forming. Epigenetic modifications have been shown to play a role in the pathogenesis of cancer as well as autoimmune and inflammatory disorders. Recent publication reports epigenetic modifications in keloid fibroblasts that include an altered pattern of DNA methylation and histone acetylation. Therefore, the field of epigenetics may provide a new therapeutic idea for keloid treatment strategies. Currently, there is some evidence from experimental studies that histone deacetylase (HDAC) inhibitor Trichostatin A (TSA) causes abrogation of TGF-ß1 induced collagen synthesis in skin fibroblasts. Furthermore, TSA could suppress proliferation and induce apoptosis in a broad spectrum of tumor cells both in vitro and in vivo. These findings suggest that TSA could also cause abrogation of TGF-ß1 induced collagen synthesis and induce apoptosis of proliferating keloid fibroblasts.

[Establishment of new vessels model by implantation of VEGF165 in mouse].

OBJECTIVE: To investigate the feasibility of establishing a murine new vessels model with Lentiviral vector (LVs) mediated human vascular endothelial growth factor-165 (pcDNA3.1/ VEGF165) gene. METHODS: Lentivirus plasmid carrying a human VEGF165 was constructed and was used to transfect mouse's NIH/3T3 cells. The NIH/3T3 cells with high secretion of VEGF were injected into the skeletal muscle of mouse to establish a mouse new vessels model by implantation of vascular endothelium growth factor (VEGF) gene. The external secretion of VEGF was measured with ELISA. Histological examination was carried out after injection. The expression of CD31 was assessed with immunohistochemical method. RESULTS: The lenti-VEGF165-EGFP was correctly constructed and confirmed by restriction endonuclease analysis, polymerase chain reaction and DNA sequencing analysis. Lentivirus plasmid carrying a human VEGF165 was constructed. lenti-VEGF165-EGFP was used to transfect mouse's NIH/ 3T3 cells, and human VEGF165 gene was assessed. NIH/3T3 cells mediated VEGF gene implantation can produce stable and effective mouse new vessels model. The external secretion of VEGF in peripheral blood was measured with ELISA. The legs became swollen in experimental group 14 d after injection. It found the cells expression of CD31 44 d after injection, and histological analysis showed the swollen tissue was composed of small new vessels. CONCLUSIONS: NIH/3T3 cells mediated VEGF gene implantation can produce stable and effective mouse new vessels model.

[Study on the effect of CD4+CD25+ regulatory T cell adoptive transfusion on humoral immune function in rat composite tissue allotransplantation model].

OBJECTIVE: To approach the effect of the donor antigenic specificity CD4+CD25+ regulatory T cell (Treg) on cellular immune tolerance function in rat composite tissue allotransplantation (CTA). METHODS: Use the method of immunomagnetic beads to separate CD4+CD25+ Treg, (1 x 10(6))CD4+CD25+ Treg was transfused to rat CTA model. Collected peripheral blood 30 days after operation, and used nylon wool column to separate B cell and T cell. With the stimulation of IgM, detected B cell proliferation and the level of IgG and IgA in serum. Observed the effect of CD4+CD25+ Treg on B cell and T cell function and the survival of allotransplants, and analyzed the data by statistics. RESULTS: The purity of separated CD4+CD25+ Treg was 95.6%. The CPM of T cell of normal control group, topical intervention group, systemic intervention group and non-intervention group were (2436 +/- 358), (2273 +/- 136), (2338 +/- 228) and (3749 +/- 245). The CPM of B cells of normal control group, topical intervention group, systemic intervention group and non-intervention group were (2418 +/- 348), (2252 +/- 127), (2315 +/- 218) and (3720 +/- 224), there was a significant difference in these groups (P < 0.01). The serum level of IgG and IgA of topical intervention group and systemic intervention group were (12.56 +/- 1.30), (2.38 +/- 0.21), (13.48 +/- 1.23) and (2.86 +/- 0.24) g/L, and of normal control group was (12.35 +/- 1.28), (2.36 +/- 0.12) g/L, had no significant difference (P > 0.05). But Treg of non-intervention group was (16.58 +/- 1.12), (3.75 +/- 0.37) g/L, there was a significant difference in the non-intervention group and the three above groups (P < 0.01). The survival time of CTA in intervention of local and systemic groups were (97 +/- 13) and (63 +/- 10) d, which were significant longer than the non-intervention group [(22 +/- 8) d, P < 0.01]. CONCLUSIONS: Donor antigen specific CD4+CD25+ Treg has significantly inhibited B cell and T cell function. It can induce immune tolerance and extend the survival time of CTA; as well local application is better than systemic.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist inhibits transforming growth factor-beta1 and matrix production in human dermal fibroblasts.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists are increasingly used in patients with diabetes, and some studies have suggested a beneficial effect on organ fibrosis, but their effects on dermal cell growth and extracellular matrix (ECM) turnover are unknown. To investigate the effect of the PPAR-gamma agonist troglitazone on cell growth and matrix production in human dermal fibroblasts (HDF), HDF were cultured and grown in a different concentration of troglitazone. PPAR-gamma expression and matrix production were measured in HDF in the presence of troglitazone. The mRNA expressions of TGF-beta1, collagen I (Col I) and fibronectin (FN) were determined by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). The protein of transforming growth factor-beta1 (TGF-beta1) was determined by enzyme-linked immunosorbent assay (ELISA) and proteins of Col I and FN were determined by Western blotting. The mRNA expression of TGF-beta1, Col I and FN were significantly decreased in HDF in 15-30 micromol l(-1) troglitazone compared to the control group with Dulbecco's modified Eagle's medium (P<0.01). An obvious decrease of TGF-beta1 protein was found in troglitazone-treated groups as compared to the control group (P<0.05). Exposure of HDF to troglitazone reduced col I secretion (P<0.05), and fibronectin secretion (P<0.05). This study suggests that PPAR-gamma agonist will provide a novel approach with therapeutic potential in dermal fibrosis, such as hypertrophic scar, keloid and so on.

[Experimental study on effect of hirudin in inhibiting hyperplastic scar fibroblasts].

OBJECTIVE: To study the effect of hirudin on the function of human hyperplastic scar fibroblasts (HSFBs). METHODS: HSFBs were cultured in vitro. Hirudin solution in the concentration of 1, 10, and 50 kU/L was respectively added into DMEM culture medium to form 1, 10, and 50 kU/L hirudin groups, with 9 wells in each group. HSFBs cultured without hirudin were set up as control group. Cell inhibition rate, secretion level of TGF-beta1 from cells, and expression levels of mRNA of type I and III precollagen were determined at 24, 48, and 72 h after culture. RESULTS: Inhibition rates of HSFBs growth was respectively (29.3 +/- 0.9)%, (30.1 +/- 0.3)%, and (45.2 +/- 1.9)% when cultured with 10 kU/L hirudin for 24, 48, and 72 hs, which were higher than those in control group [(0.0 +/- 0.0)%, P < 0.05]. There was statistically significant difference between control group and 1 and 50 kU/L hirudin groups in the inhibition rates of HSFBs at some time points (P < 0.05). Secretion level of TGF-beta1 of HSFBs in 1, 10, 50 kU/L hirudin groups was respectively (228.5 +/- 1.8), (210.5 +/- 11.1), and (168.5 +/- 14.1) pg/mL when cultured for 48 hs, of which the last 2 figures were significantly lower than that of control group [(265.0 +/- 1.5) pg/mL, P < 0.05]. Hirudin in the concentration of 10 and 50 kU/L could inhibit the expression of mRNA of type I and III precollagen in HSFBs. CONCLUSIONS: Hirudin solution in the concentration of 10 and 50 kU/L can inhibit the proliferation of HSFBs and secretion of TGF-beta1 and collagen in certain degree.

Effect of camptothecin on collagen synthesis in fibroblasts from patients with keloid.

Keloids are distinguished by substantial deposition of collagen in the dermis, resulting in an imbalanced production and aggregation of extra cellular matrix. This study was undertaken to evaluate the effects of the topoisomerase I inhibitor camptothecin (CPT) on collagen synthesis in the activated dermal fibroblasts from healthy donors and patients with keloid. The fibroblasts were cultured in the presence or absence of CPT. Cellular toxicity assay was determined by MTT analysis. The expression of type I collagen and type III collagen was studied both at the transcriptional and post-transcriptional levels, using conventional quantitative real-time reverse transcription PCR and Western blotting. Results showed that there was predominantly a clear and dose-dependent decrease in the synthesis of collagen 1, not collagen 3, in keloid fibroblasts without significantly cellular toxicity. The CPT had an activity on the regulation of the ratio of type I/III collagen in the metabolism of keloid fibroblasts by inhibiting the secretion of type I collagen. The data suggest that the inhibitory effect of CPT, a topoisomerase I inhibitor, on collagen synthesis may be an effective treatment for limiting fibrosis in keloid patients.

Activation of peroxisome proliferator-activated receptor-gamma inhibits transforming growth factor-beta1 induction of connective tissue growth factor and extracellular matrix in hypertrophic scar fibroblasts in vitro.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) ligands have been recently reported to have beneficial effects on organ fibrosis. However, their effects on extracellular matrix (ECM) turnover in hypertrophic scar fibroblasts (HSFs), and the related molecular mechanisms are unknown. HSFs were cultured and exposed to different concentration PPAR-gamma ligands in the presence of transforming growth factor-beta1 (TGF-beta1). In growth-arrested HSFs, a PPAR-gamma natural ligand (15-deoxy-D12,14-prostaglandin J2, 15d-PGJ2) and a synthetic ligand (GW7845) dose-dependently attenuated TGFbeta1-induced expression of Connective tissue growth factor (CTGF), collagens and fibronectin. Furthermore, the suppression of CTGF mRNA and protein expression are relieved by pretreatment with an antagonist of PPAR-gamma (GW9662). Moreover, GW7845 and 15d-PGJ2 partially inhibited the expression and phosphorylation of the TGF-beta1/Smad pathway. These results suggest that in TGFbeta1-stimulated HSFs, PPAR-gamma ligands caused an antiproliferative effect and reduced ECM production through mechanisms that included reducing CTGF expression, and a crosstalk between PPAR-gamma and Smad may be involved in the inhibitory effects of PPAR-gamma ligands.

Angiotensin II activates connective tissue growth factor and induces extracellular matrix changes involving Smad/activation and p38 mitogen-activated protein kinase signalling pathways in human dermal fibroblasts.

Angiotensin II (Ang II) stimulation has been shown to regulate proliferation of skin fibroblasts and the production of extracellular matrix, which are very important processes in skin wound healing and fibrosis; however, there is little knowledge about the mechanisms involved in this process. We investigated the molecular aspects of this system with regards to Ang II in human dermal fibroblasts (HDF) and its potential role in fibrosis. Fibroblasts derived from human skin were subjected to examine differential relative gene and protein expression after transfection with specific reporter expression vectors and Ang II in vitro. In growth-arrested HDFs, Ang II treatment for 20 min caused acute activation of Smad2 phosphorylation, Smad overexpression and Smad-dependent gene transcription. The angiotensin type 1 (AT1) antagonist losartan diminished Ang II-induced Smad activation. The blockade of endogenous transforming growth factor-beta1 did modify the activation of Smad caused by Ang II. The p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 diminished Ang II-induced Smad2 phosphorylation. Transient transfection with Smad7, which interferes with receptor-mediated activation of Smad2, diminished Ang II-induced connective tissue growth factor promoter activation, gene and protein expression and fibronectin, type I procollagen and type III procollagen overexpression, showing that Smad activation is involved in Ang II-induced dermal fibrosis. Our results show that Ang II activation of Smad2 occurs via the AT1 receptor, but not the AT2 receptor. Activation of Smad2 required p38 MAPK but not p42/p44 MAPK or the epidermal growth factor receptor.

Possibilities and potential roles of estrogen in the pathogenesis of proliferation hemangiomas formation.

Hemangiomas, often categorized as angiogenic diseases, are the most common tumors of infancy, the life span of which is generally divided into proliferating phase, involuting phase, and involuted phase. Despite their high prevalence, the mechanism leading to proliferation hemangiomas formation is poorly understood and the best approach to their management remains controversial. None of the current therapeutic modalities is ideal, partly because the pathogenesis of hemangioma and the mechanism of its proliferation are far from clear. Many clues reveal that estrogen has an important role in developing the vascular system, experimental and clinical evidences accumulated in recent years also suggest the potential for estrogen to influence neovascularization. Based on those, we hypothesize that estrogen play a potential role in the development of hemangiomas, mainly by regulating some key angiogenic factors, including MMP-9, EPCs, VEGF, NO, etc. Accepting the hypothesis to be correct, a therapy that identify estrogen as a potential target for the design of new, more specific treatments can be used to prevent the proliferation hemangiomas formation. The hypothesis may lead a new direction in the study of mechanisms for proliferation hemangiomas formation, and further study of the precise mechanisms for estrogen-induced hemangiomas will produce effective antiestrogens and estrogen receptor antagonists as new medication for the very difficult problem.

Infantile hemangioma is originated from placental trophoblast, fact or fiction?

Infantile hemangiomas are common, benign tumors, distinctive for their perinatal presentation, rapid growth and subsequent involution. Hemangiomas can pose serious concerns to the cosmetic and psychosocial development of the afflicted child, but none of the current therapeutic modalities is ideal to date, partly because the origin of the pathogenic ECs in infantile hemangioma is unknown. Many clues and evidences suggest a link between infantile hemangiomas and the maternal placental trophoblasts. Shared expression of distinct endothelial markers in hemangioma and placental tissues raises a possibility that infantile hemangioma is originated from placental trophoblast. Moreover, the findings of a very high similarity between the transcriptomes of placenta and hemangioma provide strong support for this theory. Furthermore, epidemiologic and clinical evidences accumulated in recent years also suggest the placental trophoblast as the cell of origin for infantile hemangioma. These findings imply a unique relationship between hemangioma and the placental trophoblast and suggest a hypothesis that infantile hemangioma is originated from placental trophoblast. The hypothesis could provide new understanding of these vascular tumors of childhood and may become the most promising research fields for the etiology of infantile hemangiomas. Further study of the precise mechanisms for the placental trophoblast originated hemangiomas will produce new preventive strategies and therapeutic avenues, possibly immunologic treatment, to the very difficult problem.

Inhibition of vascular endothelial growth factor expression in keloid fibroblasts by vector-mediated vascular endothelial growth factor shRNA: a therapeutic potential strategy for keloid.

Vascular endothelial growth factor (VEGF) plays important roles in the regulation of angiogenesis and inflammation in both pathological and physiological wound repair. Several strategies have been developed for keloid therapy; however, a universally effective treatment has not been explored to date. In this study, three potential short interfering RNA (siRNA) sequences for the VEGF gene were cloned into expression plasmids and transfected into keloid fibroblasts. PGC-VEGF shRNA 2 (short hairpin RNA 2) plasmid significantly inhibited VEGF expression determined by real-time polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA), and fibroblasts growth was also significantly by (methyl thiazolyl tetrazolium) MTT assay and apoptosis detection, whereas the control transfection showed no obviously effects. Plasminogen activator inhibitor-1 (PAI-1) expression in pGC-VEGF shRNA2 group was also obviously downregulated when compared to the pGC-VEGF shRNA negative control and mock group. These results suggest that modulation of VEGF production by vector-based RNAi in keloid fibroblasts may be a therapeutic potential strategy for keloid.

Proliferation hemangiomas formation through dual mechanism of vascular endothelial growth factor mediated endothelial progenitor cells proliferation and mobilization through matrix metalloproteinases 9.

Infantile hemangioma is the most common tumor of infancy and the mechanism leading to proliferation hemangiomas formation is poorly understood and currently no successful treatment modality exists. We hypothesize that EPCs formed during proliferation hemangiomas, as the result of vascular endothelial growth factor (VEGF) stimulation through MMP9, play the major role in the control of cell proliferation and capillary-like vessels production. Accepting the hypothesis to be correct, a therapy that inhibits EPC mobilization and proliferation can be used to prevent the proliferation hemangiomas formation. Current therapies are only partially effective and safe because they could not eliminate all the relative factors of proliferation hemangiomas formation at all, such as: EPCs in the peripheral blood, and at the same time inducing death (apoptosis and necrosis) of other normal cells. A more efficient prevention of proliferation hemangiomas could be achieved using specific drugs or biologic methods that inhibit EPC mobilization and proliferation. Therapy based on gene therapy, capable to specifically inhibit VEGF and MMP9 expression in gene level, can be possibly effective.

[Effects of mouse NIH3T3 cells transfected with VEGF gene on neovascularization of ischemic flaps].

OBJECTIVE: To investigate the feasibility of applying NIH3T3 cells transfected by VEGF gene to the treatment of ischemic random skin flaps. METHODS: Plasmid PcDNA3.1(-)/VEGF(165) containing VEGF gene was transduced into the mouse NIH3T3 cells by liposome. Immunohistochemistry was used to detect the expression of VEGF protein of mouse NIH/3T3 cells in vitro. The NIH3T3 cells were stained with CM-DiI before the transplantation. Thirty mice were randomized into 3 groups: Groups A, B and C, and were respectively injected with NIH/3T3 cells transfected with PcDNA3.1(-)/VEGF(165) plasmid, NIH/3T3 cells and medium only. On the 4th day after the injection, random dorsal skin flaps with an area of 4.0 cm x 1.5 cm were established. The survival, neovascularization and blood flow recovery of the flaps were detected. RESULTS: VEGF-transduced NIH3T3 cells expressed VEGF highly in vitro and in vivo. The results showed that flap survival rate in group A (95.1% +/- 3.1%) was significantly higher than those in group B (37.4% +/- 6.3%) and group C (26.2% +/- 5.6%). The capillary density and the blood perfusion of the flaps in group A were significantly higher than those in other two groups. CONCLUSIONS: VEGF-transfected NIH3T3 cells can improve ischemic flap neovascularization and extend survival areas.

[Experimental study of transplanted endothelial progenitor cells transfected with VEGF165 gene augment the survival volume of transplanted fat tissue].

OBJECTIVE: To investigate the feasibility of transplanting endothelial progenitor cells (EPCs) transfected with VEGF165 gene to free transplanted fat tissue for increasing neovascularization and the survival. METHODS: EPCs isolated from human cord blood were cultured in vitro and identified by immunocytochemistry. After transfection by VEGF165 gene, the expression of VEGF was assessed using ELISA. Then EPCs with (VEGF gene transfection group) and without VEGF165 gene transfection (EPCs group) were transplanted to free transplanted fat tissue at 18 nude mice's back, and nine nude mice transplanted with free fat tissue were injected with M199 (control group). CM-DiI was used to trace the transplanted cells. The capillary density of transplanted fat tissue was detected by CD34 immunohistochemistry. RESULTS: EPCs expressed cell markers CD34, KDR and CD133. After transfection, the expression of VEGF was positive. Transplanted EPCs survived and proliferated, and transplanted EPCs were incorporated into the capillary networks in the transplanted fat tissue. The percent of survival volume of transplanted fat tissue of VEGF gene transfection group was (96.2 +/- 8.6)%, significantly higher than that of the EPCs group [(75.3 +/- 6.8)%, P < 0.05) and M199 group [(40.2 +/- 2.5)%, P < 0.05). The capillary density of transplanted fat tissue of VEGF gene transfection group was significantly higher than those of the EPCs group and M199 group (P < 0.05). CONCLUSIONS: EPCs from human cord blood can increase free transplanted fat tissue neovascularization and the survival volume, and the ability of promoting neovascularization of EPCs transfected with VEGF165 gene is more potent than EPCs alone.