Autograft cellular composition and outcome in myeloma patients: Results of the prospective multicenter GOA study.

BACKGROUND: Autologous stem cell transplantation (auto-SCT) is a widely used treatment option in multiple myeloma (MM) patients. The optimal graft cellular composition is not known. STUDY DESIGN AND METHODS: Autograft cellular composition was analyzed after freezing by flow cytometry in 127 MM patients participating in a prospective multicenter study. The impact of graft cellular composition on hematologic recovery and outcome after auto-SCT was evaluated. RESULTS: A higher graft CD34+ cell content predicted faster platelet recovery after auto-SCT in both the short and long term. In patients with standard-risk cytogenetics, a higher graft CD34+ count (>2.5 × 106 /kg) was linked with shorter progression-free survival (PFS; 28 vs. 46 months, p = 0.04), but there was no difference in overall survival (OS) (p = 0.53). In a multivariate model, a higher graft CD34+ CD133+ CD38- (>0.065 × 106 /kg, p = 0.009) and NK cell count (>2.5 × 106 /kg, p = 0.026), lenalidomide maintenance and standard-risk cytogenetics predicted better PFS. In contrast, a higher CD34+ count (>2.5 × 106 /kg, p = 0.015) predicted worse PFS. A very low CD3+ cell count (≤20 × 106 /kg, p = 0.001) in the infused graft and high-risk cytogenetics remained predictive of worse OS. CONCLUSIONS: Autograft cellular composition may impact outcome in MM patients after auto-SCT. More studies are needed to define optimal graft composition.

Effects of mechanical loading on human mesenchymal stem cells for cartilage tissue engineering.

Today, articular cartilage damage is a major health problem, affecting people of all ages. The existing conventional articular cartilage repair techniques, such as autologous chondrocyte implantation (ACI), microfracture, and mosaicplasty, have many shortcomings which negatively affect their clinical outcomes. Therefore, it is essential to develop an alternative and efficient articular repair technique that can address those shortcomings. Cartilage tissue engineering, which aims to create a tissue-engineered cartilage derived from human mesenchymal stem cells (MSCs), shows great promise for improving articular cartilage defect therapy. However, the use of tissue-engineered cartilage for the clinical therapy of articular cartilage defect still remains challenging. Despite the importance of mechanical loading to create a functional cartilage has been well demonstrated, the specific type of mechanical loading and its optimal loading regime is still under investigation. This review summarizes the most recent advances in the effects of mechanical loading on human MSCs. First, the existing conventional articular repair techniques and their shortcomings are highlighted. The important parameters for the evaluation of the tissue-engineered cartilage, including chondrogenic and hypertrophic differentiation of human MSCs are briefly discussed. The influence of mechanical loading on human MSCs is subsequently reviewed and the possible mechanotransduction signaling is highlighted. The development of non-hypertrophic chondrogenesis in response to the changing mechanical microenvironment will aid in the establishment of a tissue-engineered cartilage for efficient articular cartilage repair.

Autograft immune effector cells and survival in autologous peripheral blood hematopoietic stem cell transplantation.

In addition to stem cells, T-cells, natural killer cells, dendritic cells, and monocytes are also collected and infused from the autograft in patients undergoing autologous peripheral blood hematopoietic stem cell transplantation. Recent reports have shown that these autograft immune effector cells can affect the clinical outcome postautologous peripheral blood hematopoietic stem cell transplantation. In this article, I will review the clinical impact on the survival of these autograft immune effector cells conferring the concept of autologous graft versus tumor effect.

Improvement in the Retention Rate of Transplanted Fat in Muscle by Denervation.

BACKGROUND: Improvement in the retention rate of transplanted fat is currently a topic of interest. The retention of transplanted fat relies heavily on the reestablishment of blood supply and the function of the adipose-derived stem cells (ADSCs), which may both be impeded by mechanical force. However, the effect of mechanical force on the retention of adipose implants remains unclear. OBJECTIVES: This study aimed to evaluate the effectiveness of immobilization on fat retention rate. METHODS: Immobilization was carried out by denervation of the hind limb of rats to reduce the mechanical force. Sprague-Dawley (SD) rats were used, and the two hind limbs were assigned at random to the immobilization side and the control side. On average, 0.4 mL of fat was injected into the bilateral muscle and subcutaneous space of the hind limb, and 6 rats were sacrificed at each time point. The outcome measures included the retention rate, the histologic evaluation, and the density of new vessels and proliferative ADSCs. RESULTS: For the muscle fat, the retention rate improved, and more proliferative ADSCs and new vessels were found in the immobilization group. The histologic evaluation between the two sides was of no statistical significance. For the fat in the subcutaneous space, no statistical difference was observed in all the outcome measures between the two sides. CONCLUSIONS: Regional immobilization of the recipient site by denervation can improve the retention of the fat graft in muscles owing to improved density of the new vessels and proliferative ADSCs.

Plerixafor as preemptive strategy results in high success rates in autologous stem cell mobilization failure.

Plerixafor in combination with granulocyte-colony stimulating factor (G-CSF) is approved for autologous stem cell mobilization in poor mobilizing patients with multiple myeloma or malignant lymphoma. The purpose of this study was to evaluate efficacy and safety of plerixafor in an immediate rescue approach, administrated subsequently to G-CSF alone or chemotherapy and G-CSF in patients at risk for mobilization failure. Eighty-five patients mobilized with G-CSF alone or chemotherapy were included. Primary endpoint was the efficacy of the immediate rescue approach of plerixafor to achieve ≥2.0 × 106 CD34+ cells/kg for a single or ≥5 × 106 CD34+ cells/kg for a double transplantation and potential differences between G-CSF and chemotherapy-based mobilization. Secondary objectives included comparison of stem cell graft composition including CD34+ cell and lymphocyte subsets with regard to the mobilization regimen applied. No significant adverse events were recorded. A median 3.9-fold increase in CD34+ cells following plerixafor was observed, resulting in 97% patients achieving at least ≥2 × 106 CD34+ cells/kg. Significantly more differentiated granulocyte and monocyte forming myeloid progenitors were collected after chemomobilization whereas more CD19+ and natural killer cells were collected after G-CSF. Fifty-two patients underwent transplantation showing rapid and durable engraftment, irrespectively of the stem cell mobilization regimen used. The addition of plerixafor in an immediate rescue model is efficient and safe after both, G-CSF and chemomobilization and results in extremely high success rates. Whether the differences in graft composition have a clinical impact on engraftment kinetics, immunologic recovery, and graft durability have to be analysed in larger prospective studies.

Allografts supercharged with bone-marrow-derived mesenchymal stem cells possess equivalent osteogenic capacity to that of autograft: a study with long-term follow-ups of human biopsies.

PURPOSE: Bone-marrow-derived mesenchymal stem cells (BM-MSCs) have been proposed to enhance bone formation in allografts. However, it is not known whether a combination of MSCs, contained in bone marrow concentrate (BMC) and structural allograft could be better than an allograft without MSCs and equivalent to a femoral head autograft in terms of histologic bone formation and long-term cellularity in the graft. After ten years of follow-up, three types of grafts: those initially loaded with BM-MSCs; dead, irradiated allografts; autografts. MATERIALS AND METHODS: Twenty patients received acetabular grafting during hip surgery and subsequently underwent femoral hip revision eight to 13 years later (average 10 years). Revision surgery was for reasons other than graft failure. These 20 patients had received eight allografts initially loaded with BM-MSCs: six dead irradiated allografts and six autografts. The number of MSCs present in the three types of graft were evaluated at the time of initial surgery and at revision. New bone formation associated in the acetabular graft was assessed by histology and calculated as a percentage of total available bony area. RESULTS: At the most recent follow-ups (average 10 years), concentration of MSCs in allografts previously loaded with BM-MSCs was higher than that found in autografts. There were low or no MSCs found in uncharged allografts. New-bone-formation analysis showed that allografts loaded with BM-MSCs produced more new bone (35 %; range 20-50 %) compared with either uncharged allografts (9 %; range 2-15 %) or autografts (24 %; range 12-32 %). CONCLUSIONS: Our observations with allografts charged with BM-MSCs provides evidence in support of a long-term benefit of supercharging bone allografts with autologous BM-MSCs.

Immunologic Autograft Engineering and Survival in Non-Hodgkin Lymphoma.

Retrospective studies have reported that the collected and infused autograft absolute lymphocyte count (A-ALC) affects clinical outcomes after autologous peripheral hematopoietic stem cell transplantation (APHSCT). We hypothesized that manipulation of the apheresis machine to target a higher A-ALC dose would translate into prolonged progression-free survival (PFS) in patients with non-Hodgkin lymphoma (NHL) undergoing APHSCT. Between December 2007 and October 2010, we performed a double-blind, phase III, randomized study randomly assigning 122 patients with NHL to undergo collection with the Fenwal Amicus Apheresis system with our standard settings (mononuclear cells offset of 1.5 and RBC offset of 5.0) or at modified settings (mononuclear cells offset of 1.5 and RBC of 6.0). The primary endpoint was PFS. Neither PFS (hazard ratio [HR] of modified to standard, 1.13; 95% confidence interval [CI], .62 to 2.08; P = .70) nor overall survival (OS) (HR modified to standard, .85; 95% CI, .39 to 1.86; P = .68) were found to differ by collection method. Collection of A-ALC between both methods was similar. Both PFS (P = .0025; HR, 2.77; 95% CI, 1.39 to 5.52) and OS (P = .004; HR, 3.38; 95% CI, 1.27 to 9.01) were inferior in patients infused with an A-ALC < .5 × 10(9) lymphocytes/kg compared with patients infused with an A-ALC ≥ .5 × 10(9) lymphocytes/kg, regardless of the method of collection. We did not detect significant differences in clinical outcomes or in the A-ALC collection between the modified and the standard Fenwal Amicus settings; however, despite physician discretion on primary number of collections and range of cells infused, higher A-ALC infused dose were associated with better survival after APHSCT.

Blood graft cellular composition and posttransplant outcomes in myeloma patients mobilized with or without low-dose cyclophosphamide: a randomized comparison.

BACKGROUND: Autologous stem cell transplantation is a standard treatment in multiple myeloma (MM). Blood grafts are usually collected after mobilization with granulocyte-colony-stimulating factor (G-CSF) alone or in a combination with cyclophosphamide (CY). There is limited knowledge of the possible effects of different mobilization regimens on blood graft characteristics and posttransplant outcomes. STUDY DESIGN AND METHODS: Thirty-eight patients with MM were included in this study. The patients were randomly assigned at registration to mobilization with either low-dose CY plus G-CSF (Arm A) or G-CSF alone (Arm B) and received three cycles of lenalidomide, bortetzomib, and dexamethasone induction. Flow cytometry analysis of lymphocyte subsets in the blood grafts after cryopreservation was performed. Hematologic and immune recovery were evaluated up to 12 months posttransplant. RESULTS: The blood grafts in Arm A contained significantly more CD34+ cells but in Arm B there was a greater proportion of CD34+CD38- cells and higher numbers of T and B lymphocytes as well as natural killer (NK) cells. The engraftment was comparable but lymphocyte count at 15 days posttransplant was higher in Arm B (0.8 × 10(9) /L vs. 0.5 × 10(9) /L, p = 0.033). At 3 and 6 months posttransplant the total number of NK cells was also higher in G-CSF-mobilized patients. There was no difference in progression-free survival between the study arms. CONCLUSION: CY plus G-GSF yields more CD34+ cells but seems to diminish lymphocyte and NK cell counts in the grafts and hampers immune recovery after transplantation. Thus G-CSF alone might be a preferred mobilization method due to more rapid immune recovery posttransplant.

Kinetics of the use of cryopreserved autologous stem cell grafts: a GITMO-SIDEM survey.

BACKGROUND AIMS: Hematopoietic stem cell cryopreservation significantly contributed to autologous stem cell transplantation (ASCT). Cryopreserved stem cell units (SCU) are expected to be used soon after harvesting for most purposes, but, in a number of cases, they remain stored for some time, creating an increasing load for SCU depositories. Disposal policies vary widely in each center, and the existing guidelines are insufficient. METHODS: We conducted a survey of seven Gruppo Italiano Trapianto di Midollo Osseo centers to investigate the outcome of SCU harvested from January 2005 to December 2009 for ASCT. The data from 1603 collections were gathered, for a total of 5822 SCU. RESULTS: In our cohort, 79% of patients collected >5 × 106 CD34+ cells/kg, and 3.4% collected <2 × 106 CD34+ cells/kg. Up to 21% of all the patients and 42% of those with acute leukemia did not undergo reinfusion, and 37% of the cryopreserved SCU were excess, resulting from patients not reinfusing or partially reinfusing. Less than one-third of the excess SCU was disposed, and the major causes of disposal were death and, in a minority of cases, withdrawal of the indication for ASCT. In our analysis, very few first reinfusions occurred after 2 years, and those after 5 years were exceptional. Through the use of a multivariate analysis, we sought to identify the risk factors for collection non-use, independent of the centers' policies. Non-use of SCU was significantly associated with patients with acute leukemia, collections of <2 × 106 CD34/kg and lower age groups. CONCLUSIONS: These data serve as a valid basis to support rational recommendations for cost-effective storage and disposal of SCU.

Studying nerve transfers: Searching for a consensus in nerve axons count.

Axonal count is the base for efficient nerve transfer; despite its capital importance, few studies have been published on human material, most research approaches being performed on experimental animal models of nerve injury. Thus, standard analysis methods are still lacking. Quantitative data obtained have to be reproducible and comparable with published data by other research groups. To share results with the scientific community, the standardization of quantitative analysis is a fundamental step. For this purpose, the experiences of the Italian, Austrian, German, Greek, and Iberian-Latin American groups have been compared with each other and with the existing literature to reach a consensus in the fiber count and draw up a protocol that can make future studies from different centers comparable. The search for a standardization of the methodology was aimed to reduce all the factors that are associated with an increase in the variability of the results. All the preferential methods to be used have been suggested. On the other hand, alternative methods and different methods have been identified to achieve the same goal, which in our experience are completely comparable; therefore, they can be used indifferently by the different centers according to their experience and availability.

Protocols for Full Thickness Skin Wound Repair Using Prevascularized Human Mesenchymal Stem Cell Sheet.

Split thickness skin grafts (STSGs) are one of the standard treatments available for full thickness wound repair when full thickness grafts (FTGs) are not viable, such as in the case of wounds with large surface areas. The donor sites of STSGs may be harvested repeatedly, but STSG transplants are still limited by insufficient blood supply at the early stages of wound healing. Prevascularized human mesenchymal stem cell (hMSC) sheets may accelerate wound healing and improve regeneration by providing preformed vessel structures and angiogenic factors to overcome this limitation. This book chapter provides the protocol of co-culturing hMSCs and endothelial cells to attain a prevascularized hMSC cell sheet (PHCS). The protocols for implantation of the prevascularized stem cell sheet for full thickness skin wound repair in a rat autologous skin graft model as well as the evaluation of the wound healing effects are also provided.

Cell-Enriched Fat Grafting Improves Graft Retention in a Porcine Model: A Dose-Response Study of Adipose-Derived Stem Cells versus Stromal Vascular Fraction.

BACKGROUND: Cell-enrichment of fat grafts has produced encouraging results, but the optimal concentrations and types of added cells are unknown. The authors investigated the effects of enrichment with various concentrations of ex vivo-expanded adipose-derived stem/stromal cells and stromal vascular fraction on graft retention in a porcine model. METHODS: Adipose-derived stem/stromal cells were culture-expanded, and six fat grafts (30 ml) were prepared for each minipig (n = 13). The authors investigated grafts enriched with 2.5 × 10 to 20 × 10 adipose-derived stem cells/ml and stromal vascular fraction and nonenriched control grafts. Each pig served as its own control. Magnetic resonance imaging was performed immediately after grafting and 120 days postoperatively before the pigs were euthanized, and histologic samples were collected. RESULTS: The authors recorded an enhanced relative graft retention rate of 41 percent in a pool of all cell-enriched grafts compared to the nonenriched control (13.0 percent versus 9.2 percent; p = 0.0045). A comparison of all individual groups showed significantly higher graft retention in the 10 × 10-adipose-derived stem/stromal cells per milliliter group compared with the control group (p = 0.022). No significant differences were observed between the cell-enriched groups (p = 0.66). All fat grafts showed a significantly better resemblance to normal fat tissue in the periphery than in the center (p < 0.009), but no differences in overall graft morphology were observed between groups (p > 0.17). CONCLUSIONS: Cell-enriched fat grafting improved graft retention and was feasible in this porcine model. No significant differences in graft retention were observed among the various adipose-derived stem/stromal cell concentrations or between adipose-derived stem/stromal cell and stromal vascular fraction enrichment. Future studies using this model can help improve understanding of the role of adipose-derived stem/stromal cells in cell-enriched fat grafting.

Autograft microskin combined with adipose-derived stem cell enhances wound healing in a full-thickness skin defect mouse model.

OBJECTIVE: Autograft microskin transplantation has been widely used as a skin graft therapy in full-thickness skin defect. However, skin grafting failure can lead to a pathological delay wound healing due to a poor vascularization bed. Considering the active role of adipose-derived stem cell (ADSC) in promoting angiogenesis, we intend to investigate the efficacy of autograft microskin combined with ADSC transplantation for facilitating wound healing in a full-thickness skin defect mouse model. MATERIAL AND METHODS: An in vivo full-thickness skin defect mouse model was used to evaluate the contribution of transplantation microskin and ADSC in wound healing. The angiogenesis was detected by immunohistochemistry staining. In vitro paracrine signaling pathway was evaluated by protein array and Gene Ontology, Kyoto Encyclopedia of Genes and Genomes pathway, and protein-protein interaction network analysis. RESULTS: Co-transplantation of microskin and ADSC potentiated the wound healing with better epithelization, smaller scar thickness, and higher angiogenesis (CD31) in the subcutaneous layer. We found both EGF and VEGF cytokines were secreted by microskin in vitro. Additionally, secretome proteomic analysis in a co-culture system of microskin and ADSC revealed that ADSC could secrete a wide range of important molecules to form a reacting network with microskin, including VEGF, IL-6, EGF, uPAR, MCP-3, G-CSF, and Tie-2, which most likely supported the angiogenesis effect as observed. CONCLUSION: Overall, we concluded that the use of ADSC partially modulates microskin function and enhances wound healing by promoting angiogenesis in a full-thickness skin defect mouse model.

Autologous Bone Harvest in Anterior Cervical Spine Surgery: A Quantitative and Qualitative In Vitro Analysis of Cadaveric Tissue.

BACKGROUND: The cervical spine may be used as a harvesting site of local autograft material during anterior cervical discectomy and fusion procedures. We analyzed the quality and composition of bone grafts obtained from different parts of the cervical vertebrae in a cadaveric model. METHODS: Five fresh adult human cadavers with intact cervical spines were used. Using a Smith-Robinson anterior approach to expose C4-5 and C5-6 vertebrae, samples from 4 vertebral sites were harvested under a microscope. Anterior osteophytes were removed piecemeal by a Leksell rongeur (sample A). A high-speed burr was used to drill the endplates of C4-5 and C5-6 (sample C) and uncovertebral joints of C4-5 (sample B) and C5-6 (sample D). Then 20 slides (4 per cadaver) were prepared and analyzed. RESULTS: Tissue fragmentation was associated with use of the high-speed burr. Sample A had minimal tissue fragmentation. Samples B-D showed moderate to high fragmentation. Cartilage was found in all samples. Of the 20 slides, 6 contained soft tissues (sample A in 4, sample D in 2). Disc material was identified in 6 slides (sample A in 1, sample B in 4, sample D in 1). Sample A had the greatest number of intact osteocytes and chondrocytes, and sample B had the least. CONCLUSIONS: Anterior osteophytes provide the highest number of osteocytes, with the highest osteocyte/chondrocyte ratio. Osteocyte viability is a function of vertebral body site and collection technique, with fragmentation caused by use of a high-speed burr decreasing the number of viable osteocytes.

Delivery of Allogeneic Adipose Stem Cells in Polyethylene Glycol-Fibrin Hydrogels as an Adjunct to Meshed Autografts After Sharp Debridement of Deep Partial Thickness Burns.

Harvesting of autografts results in donor site morbidities and is limited in scenarios such as large total body surface area burns. In these instances, coverage is increased by meshing grafts at the expense of delayed biologic closure. Moreover, graft meshing increases the likelihood of contraction and hypertrophic scarring, limits range of motion, and worsens cosmesis. Many tissue engineering technologies have touted the promise of adipose-derived stem cells (ASCs) for burn wounds. The primary objective of the current study was to determine feasibility and efficacy of in situ ASC delivery via PEGylated fibrin (FPEG) hydrogels as adjuncts to meshed split thickness skin grafts in a porcine model. Deep partial thickness burns were created on the dorsum of anesthetized Yorkshire pigs, and subsequently debrided on post-burn day 4. After debridement, wounds were treated with: split thickness skin grafts (STSG); meshed STSG (mSTSG); and mSTSG + FPEG with increasing doses of ASCs. We show that FPEG hydrogels can be delivered in situ to prevent the contraction seen after meshing of STSG. Moreover, ASCs delivered in FPEG dose-dependently increase blood vessel size which significantly correlates with CD31 protein levels. The current study reports a dual-action adjunct therapy to autografting administered in situ, wherein FPEG acts as both scaffolding to prevent contraction, and as a delivery vehicle for ASCs to accelerate angiogenesis. This strategy may be used to incorporate other biologics for generating tissue engineered products aimed at improving wound healing and minimizing donor sites or scarring. Stem Cells Translational Medicine 2018;7:360-372.

Combination of Follicular and Epidermal Cell Suspension as a Novel Surgical Approach in Difficult-to-Treat Vitiligo: A Randomized Clinical Trial.

Importance: Epidermal cell suspension (ECS) and follicular cell suspension (FCS) are successful surgical modalities for the treatment of stable vitiligo. However, repigmentation in generalized and acrofacial vitiligo and over acral or bony sites (eg, elbows, knees, iliac crests, and malleoli), which are difficult to treat, is challenging. Objective: To study the efficacy of transplanting a combination of autologous, noncultured ECS and FCS (ECS + FCS) compared with ECS alone in stable vitiligo. Design, Setting, and Participants: A prospective, observer-blinded, active-controlled, randomized clinical trial was conducted at a tertiary care hospital, with treatment administered as an outpatient procedure. Thirty participants who had stable vitiligo with symmetrical lesions were recruited between October 18, 2013, and October 28, 2016. All of the lesions were resistant to medical modalities with minimum lesional stability of 1 year. Intent-to-treat analysis was used. Interventions: ECS + FCS was prepared by mixing equal amounts (in cell number) of FCS with ECS. After manual dermabrasion, ECS was applied to 1 lesion and ECS + FCS was applied to the anatomically based paired lesion of the same patient. No adjuvant treatment was given. Main Outcomes and Measures: Patients were followed up at 4, 8, and 16 weeks by a blinded observer and extent of repigmentation, color match, pattern of repigmentation, patient satisfaction and complications were noted. Both the visual and the computerized image analysis methods were used for outcome assessment. Cell suspensions were assessed post hoc for OCT4+ stem cell counts using flow cytometry; expression of stem cell factor and basic fibroblast growth factor was evaluated using quantitative relative messenger RNA expression. Results: Of the 30 patients included in the study, 18 (60%) were women; mean (SD) age was 23.4 (6.4) years. Seventy-four percent of the lesions (62 of 84) were difficult-to-treat vitiligo. ECS + FCS showed superior repigmentation outcomes compared with ECS: extent (76% vs 57%, P < .001), rapidity (48% vs 31%, P = .001), color match (73% vs 61%, P < .001), and patient satisfaction (mean [SD] patient global assessment score, 23.30 [6.89] vs 20.81 [6.61], P = .047). Melanocyte stem cell counts (2% in ECS + FCS vs 0.5% in ECS) as well as expression of basic fibroblast growth factor (11.8-fold) and stem cell factor (6.0-fold) were higher in ECS + FCS suspension (P<.05 for both). Conclusions and Relevance: The findings from this study establish ECS + FCS as a novel approach in vitiligo surgery for attaining good to excellent repigmentation in a short period with good color match, even in difficult-to-treat vitiligo. Trial Registration: ctri.nic.in Identifier: CTRI/2017/05/008692.

The Fate of the Adipose-Derived Stromal Cells during Angiogenesis and Adipogenesis after Cell-Assisted Lipotransfer.

BACKGROUND: Cell-assisted lipotransfer is a process in which fat grafting is supplemented with autologous adipose-derived stromal cells. Since the efficacy of the technique was demonstrated, studies have focused on the mechanism by which cell-assisted lipotransfer enhances the rate of graft survival. However, the microenvironmental changes in donor and recipient tissue associated with cell-assisted lipotransfer remain unclear. METHODS: The authors introduced an animal model of cell-assisted lipotransfer using two different transgenic reporter mice. Donor fat from green fluorescent protein-expressing C57BL/6J mice and donor adipose-derived stromal cells from DsRed-expressing C57BL/6J mice were co-transplanted into recipient C57BL/6J mice. During adipose remodeling after cell-assisted lipotransfer, the fate of each donor adipocyte and donor adipose-derived stromal cell was traced using immunofluorescent staining with the whole-mount method. RESULTS: Adipose-derived stromal cell supplementation altered inflammation and promoted angiogenesis and subsequent revascularization in recipient tissue. Tracing at postoperative week 4 revealed that surviving donor adipose-derived stromal cells participated in angiogenesis by differentiating into endothelial cells. Moreover, newly differentiated fat from donor adipose-derived stromal cells and recipient tissue integrated with surviving donor fat, leading to improved retention of the graft. Adipose-derived stromal cell supplementation resulted in a quantitative difference in angiogenesis and adipogenesis during adipose remodeling according to the concentration of adipose-derived stromal cells. CONCLUSIONS: The authors characterized the dynamic changes occurring in donor adipose-derived stromal cells and fat and recipient tissue by tracing these cellular components following cell-assisted lipotransfer. The authors' findings highlight the therapeutic value of cell-assisted lipotransfer in tissue transplantation.

Basic Science and Clinical Application of Reamed Sources for Autogenous Bone Graft Harvest.

Autologous bone graft remains the only clinically available source of graft material with osteogenic, osteoinductive, and osteoconductive properties. Although iliac crest autologous bone graft has long served as the benchmark, reamed autogenous bone graft offers several advantages. Reamed autograft has a biochemical and cellular profile that is at least equivalent, and perhaps superior, to that of iliac crest autograft. In addition, larger volumes of reamed autograft can be obtained via less-invasive techniques, giving surgeons an accessible source of mesenchymal stem cells that can be reliably and repeatedly harvested. Early clinical experience involving reamed autogenous bone graft in the management of nonunion, bone defects, and arthrodesis has been encouraging and has demonstrated the necessary properties to warrant regular consideration of reamed graft for these applications.

Early Macrophage Infiltration Improves Fat Graft Survival by Inducing Angiogenesis and Hematopoietic Stem Cell Recruitment.

BACKGROUND: Fat grafting is a popular soft-tissue filler method; however, its results are variable and technique-dependent. Macrophages are present in fat grafts and closely associated with tissue regeneration. The authors hypothesized that activation/depletion of early macrophages in transferred fat improves/impairs fat graft survival. METHODS: Mouse inguinal fat (approximately 150 mg) was transferred autologously. Fat grafting was first performed without other manipulations to obtain baseline information. Then, liposome-encapsulated clodronate and macrophage-colony stimulating factor were used in a mouse fat grafting model for local macrophage depletion or activation. The authors examined the graft stromal vascular fraction by fluorescence-activated cell sorting at 1, 2, 4, and 12 weeks after transplantation in manipulation and control groups. Graft weight, vascularization, and secreted factors were also compared. RESULTS: Early depletion of macrophages resulted in incompetent angiogenesis, feeble Sca-1/CD45 stem cell recruitment, and eventually a poor retention rate (34 ± 6 mg versus control 84 ± 15 mg; p = 0.006), whereas up-regulated macrophages allowed better angiogenesis and survival (117 ± 12 mg versus control, 84 ± 15 mg; p = 0.043). CONCLUSIONS: In fat grafting, macrophages and their polarization initiated changes in the levels of dominant secreted factors and influenced blood-derived stem cell infiltration, indicating that macrophages were crucial for tissue revascularization. The macrophage manipulation models described here show that graft macrophage number can profoundly influence graft survival.

An innovative regenerative treatment of scars with dermal micrografts.

BACKGROUND: Pathological scars occur following injuries and are often considered esthetically unattractive. Several strategies have been attempted to improve these types of scars using both surgical and nonsurgical methods. The most common treatments include cryotherapy, intralesional corticosteroid injections, 5-fluorouracil, bleomycin, interferon, and verapamil. AIMS: In this study, we aim to investigate the effectiveness of dermal autologous micrografts in the treatment of pathological scars resulting from burns, trauma, or any iatrogenic source. METHODS: We used a new clinical practice called Rigenera Protocol to obtain autologous micrografts which were in turn injectable in the patients. RESULTS: A significant improvement was observed in appearance and texture of the exaggerated scars in all cases following already 4 months of autologous micrograft treatment We have also shown that these micrografts are composed of mesenchymal stem cells and in addition, histological evaluation verified restoration of the structural layers immediately below the epidermis and a horizontal realignment of collagen fibers in the papillary dermis. CONCLUSION: Our results clearly demonstrate the optimal outcomes obtained following treatment with dermal micrografts on exaggerated scars with different etiologies. However, further studies are required to confirm the efficacy of this new technique.