Stig-Frederik Trojahn Kølle

Enrichment of autologous fat grafts with ex-vivo expanded adipose tissue-derived stem cells for graft survival: a randomised placebo-controlled trial

BACKGROUND Autologous fat grafting is increasingly used in reconstructive surgery. However, resorption rates ranging from 25% to 80% have been reported. Therefore, methods to increase graft viability are needed. Here, we report the results of a triple-blind, placebo-controlled trial to compare the survival of fat grafts enriched with autologous adipose-derived stem cells (ASCs) versus non-enriched fat grafts. METHODS Healthy participants underwent two liposuctions taken 14 days apart: one for ASC isolation and ex-vivo expansion, and another for the preparation of fat grafts. Two purified fat grafts (30 mL each) taken from the second liposuction were prepared for each participant. One graft was enriched with ASCs (20 × 10(6) cells per mL fat), and another graft without ASC enrichment served as a control. The fat grafts were injected subcutaneously as a bolus to the posterior part of the right and left upper arm according to the randomisation sequence. The volumes of injected fat grafts were measured by MRI immediately after injection and after 121 days before surgical removal. The primary goal was to compare the residual graft volumes of ASC-enriched grafts with those of control grafts. This study is registered at www.clinicaltrialsregister.eu, number 2010-023006-12. FINDINGS 13 participants were enrolled, three of whom were excluded. Compared with the control grafts, the ASC-enriched fat grafts had significantly higher residual volumes: 23·00 (95% CI 20·57-25·43) cm(3) versus 4·66 (3·16-6·16) cm(3) for the controls, corresponding to 80·9% (76·6-85·2) versus 16·3% (11·1-21·4) of the initial volumes, respectively (p<0·0001). The difference between the groups was 18·34 (95% CI 15·70-20·98) cm(3), equivalent to 64·6% (57·1-72·1; p<0·0001). No serious adverse events were noted. INTERPRETATION The procedure of ASC-enriched fat grafting had excellent feasibility and safety. These promising results add significantly to the prospect of stem cell use in clinical settings, and indicate that ASC graft enrichment could render lipofilling a reliable alternative to major tissue augmentation, such as breast surgery, with allogeneic material or major flap surgery. FUNDING Danish Cancer Society, Centre of Head and Orthopaedics Rigshospitalet, and Moalem Weitemeyer Bendtsen.

Pooled human platelet lysate versus fetal bovine serum—investigating the proliferation rate, chromosome stability and angiogenic potential of human adipose tissue-derived stem cells intended for clinical use

BACKGROUND AIMS Because of an increasing focus on the use of adipose-derived stem cells (ASCs) in clinical trials, the culture conditions for these cells are being optimized. We compared the proliferation rates and chromosomal stability of ASCs that had been cultured in Dulbeccos modified Eagles Medium (DMEM) supplemented with either pooled human platelet lysate (pHPL) or clinical-grade fetal bovine serum (FBS) (DMEM(pHPL) versus DMEM(FBS)). METHODS ASCs from four healthy donors were cultured in either DMEM(pHPL) or DMEM(FBS), and the population doubling time (PDT) was calculated. ASCs from two of the donors were expanded in DMEM(pHPL) or DMEM(FBS) and cultured for the final week before harvesting with or without the addition of vascular endothelial growth factor. We assessed the chromosomal stability (through the use of array comparative genomic hybridization), the expression of ASC and endothelial surface markers and the differentiation and angiogenic potential of these cells. RESULTS The ASCs that were cultured in pHPL exhibited a significantly shorter PDT of 29.6 h (95% confidence interval, 22.3-41.9 h) compared with those cultured in FBS, for which the PDT was 123.9 h (95% confidence interval, 95.6-176.2 h). Comparative genomic hybridization analyses revealed no chromosomal aberrations. Cell differentiation, capillary structure formation and cell-surface marker expression were generally unaffected by the type of medium supplement that was used or by the addition of vascular endothelial growth factor. CONCLUSIONS We observed that the use of pHPL as a growth supplement for ASCs facilitated a significantly higher proliferation rate compared with FBS without compromising genomic stability or differentiation capacity.

Mesenchymal stem cell therapy for salivary gland dysfunction and xerostomia: a systematic review of preclinical studies.

The most severe forms of xerostomia and salivary gland dysfunction, as well as a severely reduced quality of life, are seen in Sjögren syndrome (SS) and after radiotherapy for head and neck cancer. For both conditions, no effective regenerative therapies yet exist. Thus, the aim of this article was to assess, through systematic review, the potential benefit of mesenchymal stem cell (MSC) therapy in radiation-induced and SS-related salivary gland dysfunction and xerostomia. We searched PubMed/MEDLINE, Embase, Web of Science, the Cochrane Database of Systematic Reviews, the World Health Organization Clinical Trials Registry Platform, and Google Scholar. We identified 6 separate study comparisons eligible for inclusion. Owing to the limited number of studies, we conclude that more randomized, adequately powered clinical trials are needed to validate the potential beneficial effect of MSCs on salivary gland dysfunction and xerostomia. Nonetheless, the preliminary studies identified in the present review were encouraging for further research.

Overcoming the bottleneck of platelet lysate supply in large-scale clinical expansion of adipose-derived stem cells: A comparison of fresh versus three types of platelet lysates from outdated buffy coat–derived platelet concentrates

BACKGROUND Platelet lysates (PL) represent a promising replacement for xenogenic growth supplement for adipose-derived stem cell (ASC) expansions. However, fresh platelets from human blood donors are not clinically feasible for large-scale cell expansion based on their limited supply. Therefore, we tested PLs prepared via three methods from outdated buffy coat-derived platelet concentrates (PCs) to establish an efficient and feasible expansion of ASCs for clinical use. METHODS PLs were prepared by the freeze-thaw method from freshly drawn platelets or from outdated buffy coat-derived PCs stored in the platelet additive solution, InterSol. Three types of PLs were prepared from outdated PCs with platelets suspended in either (1) InterSol (not manipulated), (2) InterSol + supplemented with plasma or (3) plasma alone (InterSol removed). Using these PLs, we compared ASC population doubling time, cell yield, differentiation potential and cell surface markers. Gene expression profiles were analyzed using microarray assays, and growth factor concentrations in the cell culture medium were measured using enzyme-linked immunosorbent assay (ELISA). RESULTS Of the three PL compositions produced from outdated PCs, removal of Intersol and resuspension in plasma prior to the first freezing process was overall the best. This specific outdated PL induced ASC growth kinetics, surface markers, plastic adherence and differentiation potentials comparable with PL from fresh platelets. ASCs expanded in PL from fresh versus outdated PCs exhibited different expressions of 17 overlapping genes, of which 10 were involved in cellular proliferation, although not significantly reflected by cell growth. Only minor differences in growth factor turnover were observed. CONCLUSION PLs from outdated platelets may be an efficient and reliable source of human growth supplement allowing for large-scale ASC expansion for clinical use.

Giant congenital melanocytic nevus: report from 30 years of experience in a single department.

AbstractGiant congenital melanocytic nevi (GCMN) occur in 1:20,000 livebirths and are associated with increased risk of malignant transformation. The treatment of GCMN from 1981 to 2010 in a tertiary referral center was reviewed evaluating the modalities used, cosmetic results, associated complications, and malignant transformation. Of 35 patients, 25 underwent surgery. Curettage was most frequently used (64%) followed by excision and tissue expansion (20%). Six percent of the patients treated with curettage, and 78% of the patients who received excision surgery required more than 1 planned procedure, and 25% versus 44% required unplanned additional surgery, respectively. Complications were noted in 25% and 67% of the patients, respectively. Cosmetic result was satisfying in 76% of patients without difference between the groups. No malignant transformation was found during a mean follow-up of 11 years. Curettage is a gentle alternative to excision with a lower complication rate and good cosmetic outcome.

Avoiding a Systematic Error in Assessing Fat Graft Survival in the Breast with Repeated Magnetic Resonance Imaging.

Summary: Several techniques for measuring breast volume (BV) are based on examining the breast on magnetic resonance imaging. However, when techniques designed to measure total BV are used to quantify BV changes, for example, after fat grafting, a systematic error is introduced because BV changes lead to contour alterations of the breast. The volume of the altered breast includes not only the injected volume but also tissue previously surrounding the breast. Therefore, the quantitative difference in BV before and after augmentation will differ from the injected volume. Here, we present a new technique to measure BV changes that compensates for this systematic error by defining the boundaries of the breast to immovable osseous pointers. This approach avoids the misinterpretation of tissue included within the expanded boundaries as graft tissue. This new method of analysis may be a reliable tool for assessing BV changes to determine fat graft retention and may be useful for evaluating and comparing available surgical techniques for breast augmentation and reconstruction using fat grafting.

Closure Of Thoracic Wall Defect Using Breast Implant Capsule Tissue As A Rotation Flap - A Case Report

Abstract A 70-year old woman underwent thoracic surgery resulting in rupture of a silicone implant. During re-implantation at a later time an iatrogenic thoracic wall defect was discovered. In order to complete re-implantation the defect was closed using a rotation flap constructed from capsular tissue from the previous silicone implant.

Use of autologous fat grafting for the correction of burn scar contracture in the hand: a case report

Abstract Severe burn injuries to the hand represent a topic of great concern due to long-term complications such as hypertrofic burn scar and contracture, which may result in loss of function. We present a case of burn scar contracture in the hand of a child undergoing Z-plasty and lipofilling.

Effect, Feasibility, and Clinical Relevance of Cell Enrichment in Large Volume Fat Grafting: A Systematic Review

Large volume fat grafting is limited by unpredictable volume loss; therefore, methods of improving graft retention have been developed. Fat graft enrichment with either stromal vascular fraction (SVF) cells or adipose tissue-derived stem/stromal cells (ASCs) has been investigated in several animal and human studies, and significantly improved graft retention has been reported. Improvement of graft retention and the feasibility of these techniques are equally important in evaluating the clinical relevance of cell enrichment. We conducted a systematic search of PubMed to identify studies on fat graft enrichment that used either SVF cells or ASCs, and only studies reporting volume assessment were included. A total of 38 articles (15 human and 23 animal) were included to investigate the effects of cell enrichment on graft retention as well as the feasibility and clinical relevance of cell-enriched fat grafting. Improvements in graft retention, the SVF to fat (SVF:fat) ratio, and the ASC concentration used for enrichment were emphasized. We proposed an increased retention rate greater than 1.5-fold relative to nonenriched grafts and a maximum SVF:fat ratio of 1:1 as the thresholds for clinical relevance and feasibility, respectively. Nine studies fulfilled these criteria, whereof 6 used ASCs for enrichment. We found no convincing evidence of a clinically relevant effect of SVF enrichment in humans. ASC enrichment has shown promising results in enhancing graft retention, but additional clinical trials are needed to substantiate this claim and also determine the optimal concentration of SVF cells/ASCs for enrichment. LEVEL OF EVIDENCE 4.