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Abstract Tissue nanotransfection (TNT) topically delivers Etv2, Foxc2, and Fli1 (EFF) plasmids increasing vasculogenic fibroblasts (VF) and promoting vascularization in ischemic murine skin. Human dermal fibroblasts respond to EFF nanoelectroporation with elevated expression of endothelial genes in vitro, which is linked to increased ten-eleven translocase 1/2/3 (TET) expression. Single cell RNA sequencing dependent validation of VF induction reveals a TET-dependent transcript signature. TNTEFF also induces TET expression in vivo, and fibroblast-specific EFF overexpression leads to VF-transition, with TET-activation correlating with higher 5-hydroxymethylcytosine (5-hmC) levels in VF. VF emergence requires TET-dependent demethylation of endothelial genes in vivo, enhancing VF abundance and restoring perfusion in diabetic ischemic limbs. TNTEFF improves perfusion and wound closure in diabetic mice, while increasing VF in cultured human skin explants. Suppressed in diabetes, TET1/2/3 play a critical role in TNT-mediated VF formation which supports de novo blood vessel development to rescue diabetic ischemic tissue.

Autologous fat grafting, or lipotransfer, is an important surgical approach to relocate adipose tissue within an individual to create volume. While used extensively in plastic and reconstructive surgery, significant drawbacks exist, including unpredictable volume retention. Thus, considerable research has been undertaken to identify surgical or therapeutic approaches that improve outcomes, primarily utilizing a xenograft immunocompromised mouse model. Large animal models are an important step in translating preclinical laboratory studies to the clinic, and previous studies utilizing pigs have been applied successfully for fat grafting research, but protocol variability exists across studies, and no previous publication has adequately described the impact of the swine breed on the experimental outcomes. In this report, we provide information on the critical attributes of the swine fat grafting model, including the following: (1) model selection; (2) donor site and surgical harvest approach; (3) tissue processing; (4) recipient site location and preparation; (5) post-operative care; and (6) longitudinal fat grafting assessments. Our experience comparing the use of Yorkshire and Yucatan breeds in our model showed that Yorkshire adipose tissue was fibrotic, extremely difficult to obtain through liposuction, and labor intensive to process into injectable formats. Alternatively, Yucatan adipose was more similar to human tissue, could be readily obtained through the surgical excision of inguinal fat pads, was amenable to mincing with surgical scissors, and yielded injectable tissue with a 95% efficiency. We determined that generation of a surgical pocket reduced the graft migration and spread, consequently facilitating the graft retrieval without significantly impacting retention. Using 5 cc grafts, the ultimate 3-month volume retention in 16 grafts was 19% ± 17% (or 1.14 cc ± 1.08 cc). While the use of ultrasound did not readily enable graft volume approximation during the study, it was a useful method to visualize the graft placement and ensure injection into the subcutaneous adipose layers.

Abstract Background Radiation therapy often leads to late radiation-induced skin fibrosis (RISF), causing movement impairment and discomfort. We conducted a comprehensive study to assess the effectiveness of metformin and adipose-derived stem cells (ASCs), whether autologous or allogeneic, individually or in combination therapy, in mitigating RISF. Methods Using a female C57BL/6J mouse model subjected to hind limb irradiation as a representative RISF model, we evaluated metformin, ASCs, or their combination in two contexts: prophylactic (started on day 1 post-irradiation) and therapeutic (initiated on day 14 post-irradiation, coinciding with fibrosis symptoms). We measured limb movement, examined skin histology, and analyzed gene expression to assess treatment efficacy. Results Prophylactic metformin and ASCs, whether autologous or allogeneic, effectively prevented late fibrosis, with metformin showing promising results. However, combination therapy did not provide additional benefits when used prophylactically. Autologous ASCs, alone or with metformin, proved most effective against late-stage RISF. Prophylactic intervention outperformed late therapy for mitigating radiation skin damage. Co-culture studies revealed that ASCs and metformin downregulated inflammation and fibrotic gene expression in both mouse and human fibroblasts. Conclusions Our study suggests metformin's potential as a prophylactic measure to prevent RISF, and the combination of ASCs and metformin holds promise for late-stage RISF treatment. These findings have clinical implications for improving the quality of life for those affected by radiation-induced skin fibrosis.

Summary: Radiation therapy can lead to late radiation-induced skin fibrosis (RISF), causing movement restriction, pain, and organ dysfunction. This study evaluated adipose-derived extracellular matrix (Ad-ECM) as a mitigator of RISF. Female C57BL/6J mice that were irradiated developed fibrosis, which was mitigated by a single local Ad-ECM injection, improving limb movement and reducing epithelium thickness and collagen deposition. Ad-ECM treatment resulted in decreased expression of pro-inflammatory and fibrotic genes, and upregulation of anti-inflammatory cytokines, promoting M2 macrophage polarization. Co-culture of irradiated human fibroblasts with Ad-ECM down-modulated fibrotic gene expression and enhanced bone marrow cell migration. Ad-ECM treatment also increased interleukin (IL)-4, IL-5, and IL-15 expression in endothelial cells, stimulating M2 macrophage polarization and alleviating RISF. Prophylactic use of Ad-ECM showed effectiveness in mitigation. This study suggests Ad-ECM’s potential in treating chronic-stage fibrosis.

Background:. Fat grafting is an effective treatment for craniofacial deformities. Stromal vascular fraction (SVF) is a concentrated form of adipose derived stem cells that can be isolated from fat. The aim of this clinical trial was to assess the impact of SVF enrichment on craniofacial fat grafting. Methods:. Twelve subjects with at least two regions of craniofacial volume deficit were enrolled, and they underwent fat grafting with SVF-enriched or standard fat grafting to each area. All patients had bilateral malar regions injected with SVF-enriched graft on one side and control standard fat grafting to the contralateral side. Outcome assessments included demographic information, volume retention determined by CT scans, SVF cell populations assessed by flow cytometry, SVF cell viability, complications, and appearance ratings. Follow-up was 9 months. Results:. All patients had improvement in appearance. There were no serious adverse events. There was no significant difference in volume retention between the SVF-enriched and control regions overall (50.3% versus 57.3%, P = 0.269) or comparing malar regions (51.4% versus 56.7%, P = 0.494). Patient age, smoking status, obesity, and diagnosis of diabetes did not impact volume retention. Cell viability was 77.4% ± 7.3%. Cellular subpopulations were 60.1% ± 11.2% adipose derived stem cells, 12.2 ± 7.0% endothelial cells, and 9.2% ± 4.4% pericytes. A strong positive correlation was found between CD146+ CD31-pericytes and volume retention (R = 0.863, P = 0.027). Conclusions:. Autologous fat transfer for reconstruction of craniofacial defects is effective and safe, leading to reliable volume retention. However, SVF enrichment does not significantly impact volume retention.

In 2009, the Association of Academic Chairmen of Plastic Surgery, now known as the American Council of Academic Plastic Surgeons (ACAPS), published a white paper endorsing the conversion of plastic surgery divisions into autonomous departments, motioning for other national organizations to follow suit. ACAPS’ rationale outlined 11 factors intended to promote the favorability of attaining departmental status within an institution. Through surveying division chiefs turned founding department chairs who successfully executed this transition, we evaluate the practicality and efficacy of these guidelines. A survey was distributed to founding chairs of plastic surgery departments that were established after ACAPS’ 2009 white paper. Information pertaining to institutions’ demographic information and respondents’ utilization of the principles and suggestions espoused in the white paper was obtained. The survey achieved an 86% response rate. The average time needed for the transition was 22 ± 12 months. Four of seven chairs were familiar with the 2009 ACAPS white paper. Garnering support from hospital administrators and institutional stakeholders, having fiscal profitability within the institution, and coordinating an integrated plastic surgery training program were ranked as the top three most important factors, respectively. This study assesses ACAPS’ recommendations on transitioning from a division to a department on the basis of perceived utility by academic leaders who recently navigated the process. The most frequently cited factors for a successful transition included rallying support from institutional stakeholders and ensuring profitability. Additionally, aligning the timing with a concurrent transition of leadership can expedite the process.

Abstract Acute radiation syndrome (ARS) is the radiation toxicity that can affect the hematopoietic, gastrointestinal, and nervous systems upon accidental radiation exposure within a short time. Currently, there are no effective and safe approaches to treat mass population exposure to ARS. Our study aimed to evaluate the therapeutic potential of allogeneic adipose‐derived stem cells (ASCs) for total body irradiation (TBI)‐induced ARS and understand the underlying mitigation mechanism. We employed 9.25 Gy TBI dose to C57BL/6 mice and studied the effect of allogeneic ASCs on mice survival and regeneration of the hematopoietic system. Our results indicate that intraperitoneal‐injected ASCs migrated to the bone marrow, rescued hematopoiesis, and improved the survival of irradiated mice. Our transwell coculture results confirmed the migration of ASCs to irradiated bone marrow and rescue hematopoietic activity. Furthermore, contact coculture of ASCs improved the survival and hematopoiesis of irradiated bone marrow in vitro. Irradiation results in DNA damage, upregulation of inflammatory signals, and apoptosis in bone marrow cells, while coculture with ASCs reduces apoptosis via activation of DNA repair and the antioxidation system. Upon exposure to irradiated bone marrow cells, ASCs secrete prosurvival and hematopoietic factors, such as GM‐CSF, MIP1α, MIP1β, LIX, KC, 1P‐10, Rantes, IL‐17, MCSF, TNFα, Eotaxin, and IP‐10, which reduces oxidative stress and rescues damaged bone marrow cells from apoptosis. Our findings suggest that allogeneic ASCs therapy is effective in mitigating TBI‐induced ARS in mice and may be beneficial for clinical adaptation to treat TBI‐induced toxicities. Further studies will help to advocate the scale‐up and adaptation of allogeneic ASCs as the radiation countermeasure.

Background: Mesenchymal stromal cell (MSC)-based cytotherapies fuel the hope for reduction of chronic systemic immunosuppression in allotransplantation, and our group has previously shown this capability for both swine and human cells. MSCs harvested from distinct anatomical locations may have different behavior and lead to different outcomes in both preclinical research and human trials. To provide an effective reference for cell therapy studies, we compared human and porcine MSCs from omental fat (O-ASC), subcutaneous fat (SC-ASC) and bone marrow (BM-MSC) under rapid culture expansion with endothelial growth medium (EGM).Methods: MSCs isolated from pigs and deceased human organ donors were compared for yield, viability, cell size, population doubling times (PDT), surface marker expression and differentiation potential after rapid expansion with EGM. Immunosuppressant toxicity on MSCs was investigated in vitro for four different standard immunosuppressive drugs. Immunomodulatory function was compared in mixed lymphocyte reaction assays (MLR) with/without immunosuppressive drug influence.Results: Human and porcine omental fat yielded significantly higher cell numbers than subcutaneous fat. Initial PDT was significantly shorter in ASCs than BM-MSCs and similar thereafter. Viability was reduced in BM-MSCs. Porcine MSCs were positive for CD29, CD44, CD90, while human MSCs expressed CD73, CD90 and CD105. All demonstrated confirmed adipogenic differentiation capacity. Cell sizes were comparable between groups and were slightly larger in human cells. Rapamycin revealed slight, mycophenolic acid strong and significant dose-dependent toxicity on viability/proliferation of almost all MSCs at therapeutic concentrations. No relevant toxicity was found for Tacrolimus and Cyclosporin A. Immunomodulatory function was dose-dependent and similar between groups. Immunosuppressants had no significant adverse effect on MSC immunomodulatory function.Discussion: MSCs from different harvest locations and donor species differ in terms of isolation yields, viability, PDT, and size. We did not detect relevant differences in immunomodulatory function with or without the presence of immunosuppressants. Human and pig O-ASC, SC-ASC and BM-MSC share similar immunomodulatory function in vitro and warrant confirmation in large animal studies. These findings should be considered in preclinical and clinical MSC applications.

Purpose: Burn and blast injuries to the face and extremities are highly morbid injuries affecting quality of life, ability to work, and psychosocial well-being. Without exception, extensive burn injuries require surgical debridement, with standard of care reconstruction involving autologous skin grafting to restore cutaneous integrity. This treatment modality is limited in extensive burns or in highly visible areas by lack of donor site and/or soft tissue deficits resulting in significant disfigurement. Hypodermal restoration via autologous adipose transplantation provides padding for the overlying skin, helps restore native features, and enhances contour and texture. However, this technique is limited by graft retention and often requires multiple rounds of grafting and consequently, multiple rounds of surgery, each with separate anesthesia, to achieve adequate results. The goal of this study was to demonstrate the therapeutic validity and efficacy of utilizing cryopreserved adipose to avoid multiple liposuction events when serial skin and fat grafting procedures are performed to restore epidermal, dermal, and hypodermal integrity after full-thickness burn. Methods: Adipose was collected from female Yorkshire swine and processed day-of-collection for immediate cryopreservation. This adipose was preserved for 3 months prior to initiation of the next stage of the experiment. After three-month elapse, female Yorkshire swine received 16, 4x4 cm full-thickness burns using an electric brand. After 48 hours, eschar was removed down to fascia. Skin grafts were collected as split-thickness skin grafts. The pigs were maintained for 8 weeks from time of engraftment and interval serum, photography, ultrasound, and biopsies were collected. At 8 weeks post-engraftment animals were sacrificed and all wounds were collected for histology and proteomic evaluation. Results: Split thickness skin graft take was greater than 95% in all injuries. Adipose grafts from Group B, were noted to remain present and incorporated into the granulation tissue in absence of skin graft with viability confirmed on biopsy. Initial increase in granulation layer thickness was noted in presence of fat graft with Group B vs. Group A. On serial ultrasound assessment, penetrating adipose grafts from Group D were noted to be present without gross resorption at all time points. Cryopreserved adipose remained viable throughout the duration of the experiment with histologic evidence of incorporation at 8 weeks post-operative. Conclusion: Burn and blast injuries predominantly affect military personnel and first responders for whom improvement in protective equipment has decreased mortality without resolving the risk of morbidity to the face or extremities. Hypodermal augmentation with lipografting as part of a strategy of autologous skin grafting addresses contour deficits and skin quality, however is limited by the need for multiple liposuction and grafting procedures, requiring multiple trips to the operating room with increased surgical and anesthetic risk and high economic burden. Here we demonstrate cryopreservation of adipose as an avenue to alleviate that burn.

Purpose: Autologous fat grafting is a widely used technique in aesthetic and reconstructive surgery, however, unpredictable volume reabsorption may lead to unsatisfactory outcomes. Previously, we demonstrated that a fat-soluble Vitamin D3 analogue, calcitriol, significantly improved fat retention in a xenograft mouse model by 25% across multiple donors when injected systemically (p < 0.05). While calcitriol has minimal toxicity, is FDA approved, and has positive immunomodulatory and antioxidant properties, systemic administration bypasses key Vitamin D synthesis regulatory steps, thus increasing risk with high-dose use. We hypothesize that systemic supplementation with Vitamin D3 (cholecalciferol) will likewise improve fat-graft retention similar to calcitriol while avoiding potential regulatory and iatrogenic risk. In this study we compared in vivo human fat graft retention in mice treated with systemic cholecalciferol, calcitriol or vehicle control in a mouse xenograft model. In vitro adipose lipoaspirate culture was used to interrogate the therapeutic mechanism of action. Methods: Lipoaspirate was harvested from 6 unique donors using a 2mm cannula and used in parallel for both in vitro and in vivo studies. In vivo: 0.3mL of lipoaspirate was injected bilaterally on dorsal flanks of homozygous Foxn1nu immunocompromised mice. Calcitriol (50ng), cholecalciferol (50ng, 500ng, 5000ng) or vehicle control was administered thrice weekly by IP injection. Graft volume retention was measured at 12 weeks. In vitro: 1mL of lipoaspirate was submerged in phenol-red free DMEM (10% FBS) containing calcitriol or cholecalciferol (15.6nM, 62.5 nM or 250 nM) for 7 days with one media change. Terminal analyses include tissue weight, stromal cell viability, concentration of active vitamin D metabolite (1,25(OH)2D3), and gene upregulation by qRT-PCR. Results: Previously, we demonstrated that systemic administration of 50ng calcitriol thrice weekly significantly improved human fat graft retention across multiple donors in a mouse xenograft model. Our current in vivo data suggest 5000ng cholecalciferol is similarly effective. In-vitro assays show 62.5nM and 250nM cholecalciferol significantly increased adipose stromal cell viability compared to controls (85.3+/-2.9% and 87.7+/-3.7 versus 77.6+/-2.8%, respectively p

Critically sized defects in subcutaneous white adipose tissue result in extensive disfigurement and dysfunction and remain a reconstructive challenge for surgeons; as larger defect sizes are correlated with higher rates of complications and failure due to insufficient vascularization following implantation. Our study demonstrates, for the first time, a method to engineer perfusable, pre-vascularized, high-density adipose grafts that combine patient-derived adipose cells with a decellularized lung matrix (DLM). The lung is one of the most vascularized organs with high flow, low resistance, and a large blood–alveolar interface separated by a thin basement membrane. For our work, the large volume capacity within the alveolar compartment was repurposed for high-density adipose cell filling, while the acellular vascular bed provided efficient graft perfusion throughout. Both adipocytes and hASCs were successfully delivered and remained in the alveolar space even after weeks of culture. While adipose-derived cells maintained their morphology and functionality in both static and perfusion DLM cultures, perfusion culture offered enhanced outcomes over static culture. Furthermore, we demonstrate that endothelial cells seamlessly integrate into the acellular vascular tree of the DLM with adipocytes. These results support that the DLM is a unique platform for creating vascularized adipose tissue grafts for large defect filling.

Background:. Biomaterials derived from human adipose extracellular matrix have shown promise in vitro and in animal studies as an off-the-shelf adipogenic matrix for sustained volume replacement. Herein, we report the results of a randomized prospective study conducted with allograft adipose matrix (AAM) grafted into the pannus of presurgical abdominoplasty patients 3 or 6 months before scheduled surgery. This is the first report of a longitudinal histologic analysis of AAM in clinical use. Methods:. Ten healthy patients undergoing elective abdominoplasty were recruited to receive AAM before surgery. Enrolled subjects were randomized into either a 3-month follow-up cohort or a 6-month follow-up cohort. Subjects were monitored for adverse events associated with AAM grafting in addition to undergoing serial biopsy. Following surgical excision of the pannus, representative samples from the AAM surgical sites were stained and evaluated with hematoxylin and eosin for tissue morphology, Masson’s trichrome for collagen, and perilipin for adipocytes. Results:. All subjects tolerated AAM with no severe adverse events reported. At 3 months following implantation, AAM remained visible within the confines of the subjects’ native surrounding adipose tissue with sparse adipocytes apparent within the matrix. By 6 months, AAM had remodeled and was primarily composed of perilipin-positive adipocytes. Histologic analysis confirmed tissue remodeling (hematoxylin and eosin), adipogenesis (perilipin), and angiogenesis (Masson’s trichrome) occurred with the presence of AAM. Conclusions:. AAM is a safe, allogeneic, off-the-shelf regenerative matrix that is adipogenic and noninflammatory and promotes angiogenesis.

Background:. Variable retention outcomes remain a significant issue in autologous fat grafting procedures. Among seemingly similar patients, using identical harvesting procedures, variability in graft retention is noted. Recent data suggest that the inherent characteristics of donor adipose tissue dictate graft healing outcomes. The goal of this study was to elucidate intrinsic qualities of human adipose tissue that confer resistance to ischemic stress to therapeutically target such mechanisms and improve overall results of fat grafts. Methods:. Whole fat from 5 female patients was cultured in vitro under severe (1% O2) and mild (8% O2) hypoxic conditions. Microarray analysis of 44 hypoxia-related genes was performed. Perilipin was used to visualize viable adipocytes. Macrophage phenotypes were identified using PCR. Results:. Analysis of adipocyte survival with perilipin suggested improved viability for tissue obtained from high BMI donors. Microarray data revealed a significant positive correlation for induced expression of ANGPTL4, a survival gene, and subject BMI (P = 0.0313) during hypoxic conditions whereas HIF1α and HIF2α genes were negatively correlated with donor BMI (P = 0.0003 and 0.0303). Interestingly, induced differentiation of proinflammatory M1 macrophages was negatively correlated with BMI under hypoxia (P = 0.0177). Conclusions:. The innate resilience of adipocytes to hypoxia and relative macrophage activation play a crucial role in fat graft retention. This study suggests that adipose tissue from high BMI donors demonstrates greater resistance to hypoxia-induced apoptosis associated with an increased expression of ANGPTL4. Therefore, therapeutic interventions that target this factor may improve clinical adipose graft survival.

Background:. Neuropathic pain is one of the more severe types of chronic pain and presents a great challenge as response to medical therapy remains often unpredictable. With the opioid epidemic and the search for ways to avoid narcotics, physicians are seeking other modalities to treat neuropathic pain. In recent years, surgeons have explored various surgical avenues to improve outcomes. The aim of this review was to evaluate the current clinical evidence regarding the efficacy of fat grafting for the treatment of neuropathic pain. Methods:. A critical review was conducted to examine the current clinical evidence of fat grafting as a therapy for neuropathic pain caused by neuromas, peripheral neuralgia, migraine and headaches, neuropathic scar pain, and postmastectomy pain syndrome. Results:. The precise mechanism role of fat grafting in modulating neuropathic pain remains unclear, but it appears to reduce pain levels through the anti-inflammatory effects of adipose-derived stem cells and mechanical cushioning by fat. Conclusions:. Fat grafting is an emerging therapy for chronic neuropathic pain of various etiologies. Although promising results have been reported, sample size and level of evidence of current studies are low. The encouraging results, however, are worthy of further clinical and scientific study. The minimally invasive nature of fat grafting and favorable risk profile make this an attractive therapy for neuropathic pain.

Purpose: Digital amputation represents a common injury requiring acute hand surgery intervention. These injuries are often complicated by pain, hypersensitivity, dysesthesia, cold intolerance, and contour deficits/pulp atrophy. Many secondary procedures exist to address these concerns; however, they are often limited by undesirable donor site morbidity and/or complex rehabilitation. There is currently no single gold standard for treatment of the dysesthetic digit. Free adipose transfer via lipofilling offers to correct these defects by providing soft, healthy bulk to the amputated site with minimal comorbidity. Here we describe a protocol and preliminary data for providers considering adipose transfer to the dysesthetic digit. Methods: We examined 113 patients who sustained digit amputations between 2010 and 2019. Patients sustained an average of 1.6+/-0.9 amputations per trauma. 13 patients were identified with chronic pain, dysethesia, cold intolerance, or hypersensitivity that persisted after therapy. Controlling for reversible nail bed pathology, 10 patients demonstrated primary chronic dysesthesia. Results: 4 of 10 patients presenting for chronic amputation stump dysesthesia elected for fat grafting to the fingertip. All patients reported improved pain and reduced dysesthesia/hypersensitivity post-intervention. 3 patients required no further intervention after one round of grafting; 1 patient underwent repeat grafting. Of the non-grafted group, 66.7% (4/6) progressed to revision amputation. There were no operative revision amputations after grafting. Conclusions: Fat grafting to the fingertip offers a simple, safe, and easily accessible technique to augment soft tissue bulk at the digital stump. Our preliminary data suggests that this may be an effective option to manage digital dysesthesia/hyperesthesia.

BackgroundVascularized composite allotransplantation opens new possibilities in reconstructive transplantation such as hand or face transplants. Lifelong immunosuppression and its side-effects are the main drawbacks of this procedure. Mesenchymal stem cells (MSCs) have clinically useful immunomodulatory effects and may be able to reduce the burden of chronic immunosuppression. Herein, we assess and compare characteristics and immunomodulatory capacities of bone marrow- and adipose tissue-derived MSCs isolated from the same human individual across defined human leukocyte antigen (HLA) barriers.Materials and methodsSamples of omental (o.) adipose tissue, subcutaneous (s.c.) adipose tissue, and bone marrow aspirate from 10 human organ donors were retrieved and MSCs isolated. Cells were characterized by flow cytometry and differentiated in three lineages: adipogenic, osteogenic, and chondrogenic. In mixed lymphocyte reactions, the ability of adipose-derived mesenchymal stem cells (ASCs) and bone marrow-derived mesenchymal stem cells (BMSCs) to suppress the immune response was assessed and compared within individual donors. HLA mismatched or mitogen stimulations were analyzed in co-culture with different MSC concentrations. Supernatants were analyzed for cytokine contents.ResultsAll cell types, s.c.ASC, o.ASC, and BMSC demonstrated individual differentiation potential and cell surface markers. Immunomodulating effects were dependent on dose and cell passage. Proliferation of responder cells was most effectively suppressed by s.c.ASCs and combination with BMSC resulted in highly efficient immunomodulation. Immunomodulation was not cell contact-dependent and cells demonstrated a specific cytokine secretion.ConclusionWhen human ASCs and BMSCs are isolated from the same individual, both show effective immunomodulation across defined HLA barriers in vitro. We demonstrate a synergistic effect when cells from the same biologic system were combined. This cell contact-independent function underlines the potential of clinical systemic application of MSCs.

The immunomodulatory potential of cell therapies using adipose-derived stem cells (ASCs) and bone marrow-derived mesenchymal stem cells (BM-MSCs) has been studied in vascularized composite allotransplantation (VCA). Most cell therapy-based experimental and clinical protocols integrate some degree of recipient conditioning/induction with antibodies or other immunosuppressive agents on the functional and morphological properties of stem cell, and consequent efficacy of therapy outcomes. We investigate the susceptibility of ASCs and BM-MSCs to anti-lymphocyte serum (ALS) and tacrolimus. Rat ASCs and BM-MSCs were exposed to varying concentrations of tacrolimus and ALS in vitro. Serum from ALS-treated animals was added to cell cultures. Viability, susceptibility, and cytotoxicity parameters were evaluated. ALS inhibited ASC and BM-MSC viability and susceptibility in vitro in a dose dependent manner. ASCs were more susceptible to both ALS and tacrolimus than BM-MSCs. Trypsinized and adherent ASCs were significantly smaller than BM-MSCs. This is the first report on the viability and susceptiblity characteristics of BM-MSCs or ASCs to collateral effects of ALS and tacrolimus. These in vitro insights are important regarding choice of cell type as well as concomitant conditioning agents and the logistical coordination of the timing, dosing and frequency of drug or cell therapy in SOT or VCA protocols.

Conventional breast cancer extirpation involves resection of parts of or the whole gland, resulting in asymmetry and disfiguration. Given the unsatisfactory aesthetic outcomes, patients often desire postmastectomy reconstructive procedures. Autologous fat grafting has been proposed for reconstructive purposes for decades to restore form and anatomy after mastectomy. Fat has the inherent advantage of being autologous tissue and the most natural-appearing filler, but given its inconsistent engraftment and retention rates, it lacks reliability. Implementation of autologous fat grafts with cellular adjuncts, such as multipotent adipose-derived stem cells (ADSCs), has shown promising results. However, it is pertinent and critical to question whether these cells could promote any residual tumor cells to proliferate, differentiate, or metastasize or even induce de novo carcinogenesis. Thus far, preclinical and clinical study findings are discordant. A trend towards potential promotion of both breast cancer growth and invasion by ADSCs found in basic science studies was indeed not confirmed in clinical trials. Whether experimental findings eventually correlate with or will be predictive of clinical outcomes remains unclear. Herein, we aimed to concisely review current experimental findings on the interaction of mesenchymal stem cells and breast cancer, mainly focusing on ADSCs as a promising tool for regenerative medicine, and discuss the implications in clinical translation.

Background: Conventional suction-assisted lipectomy (SAL) often results in contour irregularity. Selective photothermal heating of adipose tissue by polymer-coated gold nanorods energized by an external near-infrared exposure at 800 nm is introduced in this work to facilitate fat removal. Methods: The effects of NanoLipo were examined in food-grade porcine abdominal tissue (skin, fat, and fascia) by histology. The efficacy of NanoLipo was compared with that of conventional SAL in vivo in Yucatan mini pigs by quantification of removed subcutaneous tissue and fatty acids and ultrasound measurement of adipose layer thickness. Results: NanoLipo led to the appearance of disruptions in adipose tissue that were not apparent in control groups in ex vivo samples. NanoLipo allowed removal of more subcutaneous tissue (~33% vs ~25% of removed material, P < 0.05) and approximately twice as much free fatty acids (~60% vs ~30% of removed tissue, P < 0.05) in comparison with conventional SAL. Most importantly, NanoLipo led to a greater decrease in adipose layer thickness at 1 month post surgery (P < 0.001). Conclusions: NanoLipo facilitates removal of a greater quantity of fat and requires less suction time (4 vs 10 minutes) than conventional SAL. As the safety of poly(ethylene-glycol)-coated gold nanorods is well-established, a clinical trial is currently being organized.

To test the hypothesis that the transplantation of adipose precursor cells (APCs) improves nerve regeneration and functional recovery, human APCs were transplanted into the lumen of a nerve guide in a 6-mm unilateral sciatic nerve defect in athymic rats. The three control groups for the study were biodegradable, polycaprolactone-based nerve conduit without APCs, autograft, and empty defect. Behavioral tests were performed every 3 weeks, and the sciatic functional index (SFI) was calculated based on measurements from the hindlimb prints. After 12 weeks, the nerve as well as right and left gastrocnemius muscles were removed and preserved for histological evaluation. Full regeneration of the sciatic nerve occurred on the rats that received the autograft, the guide, and the guide with APCs; no regeneration was observed on any of the rats in which the defect was left untreated (empty defect). APCs survived transplantation for up to 12 weeks in the injured peripheral nerve. No significant colocalization was observed between the immunostaining for glial fibrillary protein and anti-human lamin A/C, implying that the APCs did not differentiate into Schwann cells at the site of injury. In comparison with the rats with untreated defects, a decrease in muscle atrophy was observed on those rats that received the autograft and the guide with cells as indicated by the gastrocnemius muscle weight ratio and the muscle fiber ratio. Significant differences in SFI were observed 3 weeks postinjury between the rats in which the guide was left empty and those that received the guide with APCs; however, these differences were not observed at 12 weeks. The transplantation of APCs promoted the formation of a more robust nerve as evidenced by the results from the cross-sectional area of regenerated nerve, and the transplantation of APCs produced a decrease in muscle atrophy.