Cosmetic Breast Augmentation with Autologous Ex Vivo-Expanded Adipose-Derived Mesenchymal Stem/Stromal Cell (Stemform®)-Enriched Fat Grafts: A Study of the First Twenty-Two Real-World Patients.

BACKGROUND: Fat grafting is commonly utilized in breast surgery, and since it was first described, clinicians and researchers have stridden towards improvement of graft retention. Current advancements include adding adipose-derived mesenchymal stem/stromal cells (MSC(AT)s), which have demonstrated promise for improved graft retention. OBJECTIVES: This study reports outcomes for the first twenty-two patients undergoing breast augmentation (Stemform BA) or artificial implant replacement (Stemform AIR) with MSC(AT)-enriched fat in a real-world setting. METHODS: Autologous MSC(AT)s were isolated and expanded ex vivo, then mixed with lipoaspirate and injected as enriched fat for Stemform BA and AIR. The breast volume was measured preoperatively and at 3 and 12 months postoperative using a 3D Infinity Dual-Lens Camera and LifeVizApp software. Additionally, independent plastic surgeons evaluated clinical images, and patient satisfaction was obtained at equal time points. RESULTS: Twenty-two patients were included. All completed 3 and 12 months clinical follow-up and 3 months volume measurements. Nineteen patients completed 12 months volume measurements. The median fat graft retention at 12 months was 95.7% (IQR = 82.44-103.12%) for Stemform BA patients and 113.0% (IQR = 94.8-131.2%) for Stemform AIR patients. The Stemform BA patients had a median breast enlargement of 172.0% (IQR = 156.7-241.0%). The implant replacement volume of Stemform AIR patients was 102% (IQR = 85.1-130.3%). The patient reported 92.8% and 100% would elect to repeat treatment if they had the opportunity for Stemform BA and Stemform AIR, respectively. CONCLUSION: Breast augmentation and breast implant replacement patients receiving ex vivo-expanded MSC(AT)-enriched fat grafts had high graft retention and patient satisfaction scores. The paper confirms the clinical efficacy of using ex vivo-expanded MSC(AT)s. Level of Evidence V 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 .

Donor Lymphocyte Infusion Is a Feasible Way to Improve Survival in Patients with Acute Myeloid Leukemia and Myelodysplastic Syndromes Who Relapse after Allogeneic Stem Cell Transplantation.

INTRODUCTION: Donor lymphocyte infusion (DLI) is used to induce remission in patients who relapse after allogeneic stem cell transplantation (allo-HSCT). During the last decade, the hypomethylating agent Azacitidine has been used together with DLI for a synergistic graft-versus-leukemia (GVL) effect. Here we report results of DLI/Azacitidine treatment from a retrospective single-center study. METHODS: 50 AML/MDS patients treated for relapse after allo-HSCT between 2001 and 2020 with DLI at the Department of Hematology, at Rigshospitalet, Copenhagen University Hospital were included for analyses. A subgroup of patients who obtained complete remission (CR) after reinduction chemotherapy, received DLI in combination with low-dose (32 mg/m2) Azacitidine. RESULTS: Overall survival in all patients after DLI treatment was 59% at 2 years and 20% at 5 years. Relapse-free survival in patients in CR prior to DLI was 32% after 2 years and 7% after 5 years. In the DLI+low-dose-Azacitidine group, 5-years relapse-free survival was 40%. CONCLUSION: DLI remains an effective treatment in post-transplant relapse leaving one fifth of patients long-term survivors. Our results support the concomitant use of low-dose Azacitidine in the future use of DLI in order to enhance the GVL effect of donor lymphocytes.

DMSO (Me2SO) concentrations of 1-2% in combination with pentaisomaltose are effective for cryopreservation of T cells.

T cell based treatments in the setting of allogenic haematopoietic stem cell transplantation (HSCT) have been used for decades. In addition, the use of chimeric antigen receptor (CAR) T cells has been introduced as a promising cancer immunotherapy. A prerequisite for many of these treatments is the ability to cryopreserve the cells safely and efficiently. In the present study, we compared freezing media combinations containing pentaisomaltose and 1-2 % DMSO (PIM1 and PIM2, respectively) to 10 % DMSO and commercially available cryosolutions (CS2 and CS10, Cryostor® containing 2 and 10 % DMSO, respectively) for cryopreservation of T cells. T cells isolated from buffy coats from healthy donors were cryopreserved with different freezing media and analysed for 1) viability immediately post-thaw and the following 24 h, 2) recovery, 3) proliferative potential and 4) migration towards a gradient of SDF-1α. The results showed that PIM2 was superior to 10 % DMSO and comparable to CS10 when assessing viability. Furthermore, the results indicated that the T cells cryopreserved with 10 % DMSO showed the lowest proliferative potential. The expression levels of CXCR3, CXCR4 and VLA-4 were similar in T cells independent of the freezing media used; however, T cells cryopreserved with PIM2 demonstrated the highest migratory potential. In summary, the combination of pentaisomaltose and 1-2 % DMSO improves the cryoprotective properties compared to 10 % DMSO while achieving comparable results with CS10 and even showing improved migration towards SDF-1α. Thus, our results show promising potential for pentaisomaltose in combination with low amounts of DMSO for the cryopreservation of T cells.

Adipose-Derived Stromal/Stem Cell Culture: Effects of Different Concentrations of Human Platelet Lysate in Media.

Adipose-derived stromal/stem cells (ASCs) are being tested as a possible treatment for a wide range of diseases to exploit the immunomodulatory and regenerative potential demonstrated in vitro. Pooled human platelet lysate (pHPL) has replaced fetal bovine serum (FBS) as the preferred growth supplement because of its xeno-free origin and improved cell proliferation. Much has been done toward reducing the concentration of pHPL required when expanding ASCs. However, little is known on how increasing the concentration of pHPL affects ASC potency, which could lead to changes with possible beneficial applications. This study investigated the effect of 5, 10, or 20% pHPL in culture media on ASC proliferation and phenotypic marker expression, including chemokine receptors CXCR2, CXCR3, CXCR4, and VLA-4. Adipogenic and osteogenic properties, as well as immunosuppressive properties, including the ability to induce indoleamine-pyrrole 2,3-dioxygenase 1 (IDO1) and suppress T cell proliferation, were also examined. We observed a significant increase in cell yield (approximately 2-fold) and a corresponding reduction in population doubling time and cell volume when doubling the concentration of pHPL in the growth media. ASCs maintained expression of phenotypic surface markers CD73, CD90, and CD105 and were negative for CD45 and CD31. The ability to induce IDO1 and suppress T cell proliferation was observed as well. Adipogenesis and osteogenesis, however, seem to be increased at higher concentrations of pHPL (20% > 10% > 5%), while expression of chemokine receptors CXCR2 and CXCR3 was lower. In conclusion, increasing the pHPL concentration to 20% could be used to optimize culture conditions when producing cells for clinical treatments and may even be used to enhance beneficial ASC properties depending on the desired therapeutic effect.

Lipoaspirate Storage Time and Temperature: Effects on Stromal Vascular Fraction Quality and Cell Composition.

The adipose tissue-derived stromal vascular fraction (SVF) is a promising candidate for use in cell therapy and tissue engineering due to its regenerative and immunomodulatory properties. Some therapies are based on using the complete SVF product, whereas others depend on the expansion of adipose-derived stromal cells (ASCs) in culture. The latter application often involves a time delay between adipose tissue harvest and SVF isolation. This study investigated how storage time and temperature affected cell quality and composition. Aliquots of lipoaspirate were stored cold (4°C), at room temperature (18-20°C), or at 37°C. SVF was isolated on sequential time points over a period of 48 h, and the following were assessed: cell viability, vitality, composition, and the proliferative potential of the ASCs. When the lipoaspirate was stored cold, the viability of the SVF remained stable for up to 48 h; however, the vitality of the SVF decreased significantly after 24 h. When stored at higher temperatures (room temperature or 37°C), the vitality of the SVF decreased after 8 h. The ASC fraction in the SVF decreased rapidly after 8 h when stored at higher temperatures, whereas this change was delayed significantly when the lipoaspirate was stored cold. Tendencies towards increases in the lag phase, population doubling time (PDt), and time to reach confluency were observed when the lipoaspirate was stored at higher temperatures. The vitality of the SVF was correlated significantly with the time of the lag phase and the time required to reach confluence, whereas no correlation was observed with the PDt. Both prolonged storage time and increased temperature during lipoaspirate storage negatively affected the quality of the obtained SVF. Our results suggest that lipoaspirate should be stored for no longer than 24 h at 4°C to maintain the optimal quality for the isolation of SVF and the expansion of ASCs.

Cryopreservation of adipose-derived stromal/stem cells using 1-2% Me2SO (DMSO) in combination with pentaisomaltose: An effective and less toxic alternative to comparable freezing media.

Mesenchymal stromal/stem cells (MSCs) derived from bone marrow, umbilical cord and especially adipose tissue are increasingly being explored for their therapeutic potential to treat a wide variety of diseases. A prerequisite for most allogeneic off-the-shelf and some autologous MSC therapies is the ability to safely and efficiently cryopreserve cells during production or for storage prior to treatment. Dimethyl sulfoxide (Me2SO) is still the commonly used gold standard cryoprotectant (CPA). However, undesirable cellular impacts and side effects of Me2SO have led to an increasing demand for the development of safe and effective alternatives. This study investigated the effect of pentaisomaltose as a CPA for cryopreservation of adipose-derived stromal/stem cells (ASCs). We compared pentaisomaltose-based freezing media containing 1% Me2SO (PIM1) or 2% Me2SO (PIM2) to our in-house freezing media formulation containing 10% Me2SO (STD10) and to CryoStor freezing media containing 2% or 10% Me2SO (CS2 and CS10). We assessed the recovery of viable ASCs, their phenotype, differentiation potential, proliferation potential, and migratory potential. Further, their immunomodulatory potential was assessed by measuring their ability to suppress T cell proliferation and express immunomodulatory markers. The results showed that the post-thaw viability of ASCs cryopreserved with STD10, CS10 and PIM2 was improved compared to that of CS2. The recovery of ASCs with PIM1 and PIM2 was also improved compared to that of CS2. Proliferation and migration were comparable among the tested freezing media. The results showed no difference in the induction of PDL1, PDL2 or IDO1 expression. Nevertheless, the potential of cryopreserved ASCs to suppress T cell proliferation was reduced when the Me2SO concentration was reduced (CS10>STD10>CS2 and PIM2>PIM1). Altogether, the migratory and immunomodulatory potential combined with improved recovery indicate that the addition of pentaisomaltose in the freezing media may allow for the reduction of the Me2SO concentration to 2% while retaining a more potent cell product that what is recovered using comparable freezing media. With the desire to reduce the amount of Me2SO, these results suggest that 2% and potentially even 1% Me2SO in combination with 10% pentaisomaltose could be an effective and less toxic alternative to comparable freezing media.

Apheresis principles in a patient with chronic myeloid leukemia during pregnancy: challenges in cell separation and assessing transcript levels.

BACKGROUND: Chronic myeloid leukemia (CML) is rarely diagnosed in pregnant women. CASE REPORT: We report a case of a pregnant woman who presented with a leukocyte count of 250 × 109 cells/L at gestational age (GA) 26 weeks and was diagnosed with CML in the chronic phase. Because the patient deliberately opted out of interferon α and tyrosine kinase inhibitor treatment, the main goal was to reduce the leukocyte count to postpone delivery beyond the number of weeks considered severely premature and avoid thromboembolic complications while continuously evaluating the clinical safety of the mother and fetus. Hence therapeutic leukapheresis was initiated, and we report the first application of an apheresis approach for this procedure using the Spectra Optia instrument without sedimentation agents. Leukapheresis was conducted 2 to 4 times per week for 9 weeks. RESULTS: During treatment the leukocyte count decreased remarkably, and the patient developed lymphopenia together with a paradoxical increase in her blood platelet count. Premature labor was induced at GA 35 weeks, and a healthy boy was delivered. Thereafter, the patient initiated imatinib treatment and was in major molecular and complete cytogenetic remission after 1 year. Despite the remarkable reduction of the leukocyte count, we observed a pronounced increase in expression of BCR-ABL1 transcripts, implying the need for close monitoring of patients with CML during pregnancy. CONCLUSIONS: We report a pregnant woman who was diagnosed with CML and treated solely with apheresis procedures using the Spectra Optia instrument for 9 weeks, ensuring the safe delivery of her child.

Depletion of αß+ T and B Cells Using the CliniMACS Prodigy: Results of 10 Graft-Processing Procedures from Haploidentical Donors.

BACKGROUND: Depletion of TCRαß+ T cells and B cells with the CliniMACS Plus® has been used for haploidentical hematopoietic stem cell transplantation for a decade. The depletion procedure is time and labour demanding and with variable reported efficiencies. Recently, an automated procedure was launched for the CliniMACS Prodigy® (Miltenyi Biotec) but reported data are scarce. Here, we report the results of the first ten TCRαß+ and B cell depletion procedures for clinical use performed at our centre. MATERIALS AND METHODS: All transplants were from a parent to a child. Collection of peripheral blood stem cells was performed after filgrastim mobilisation by use of the Spectra Optia® (TerumoBCT) set on the MNC program. Because of insufficient hematopoietic stem cell mobilisation, 1 donor received additional plerixafor. RESULTS: We performed ten uncomplicated processes with the CliniMACS Prodigy. We found the results of the depletion procedures satisfactory with a median log reduction of TCRαß+ cells of -4.21 (range -3.98 to -4.74), resulting in a median number of TCRαß+ cells in the depleted product of 28.6 × 103/kg recipient weight (range 14.9-69.7 × 103/kg). The median CD34 recovery was 83% (range 70-100). To achieve a sufficient number of CD34+ cells, we performed an additional CD34+ enrichment procedure using the CliniMACS Plus for 3 patients. The B cell depletion was slightly less efficient with a median log reduction of -3.72 (range -2.83 to -4.20). CONCLUSION: Overall, we found the TCRαß and CD19 depletion procedure on the CliniMACS Prodigy easy to handle and reliable, providing reproducible good results.

Changes in Gene Expression during G-CSF-Induced Emergency Granulopoiesis in Humans.

Emergency granulopoiesis refers to the increased production of neutrophils in bone marrow and their release into circulation induced by severe infection. Several studies point to a critical role for G-CSF as the main mediator of emergency granulopoiesis. However, the consequences of G-CSF stimulation on the transcriptome of neutrophils and their precursors have not yet been investigated in humans. In this work, we examine the changes in mRNA expression induced by administration of G-CSF in vivo, as a model of emergency granulopoiesis in humans. Blood samples were collected from healthy individuals after 5 d of G-CSF administration. Neutrophil precursors were sorted into discrete stages of maturation by flow cytometry, and RNA was subjected to microarray analysis. mRNA levels were compared with previously published expression levels in corresponding populations of neutrophil precursors isolated from bone marrow of untreated, healthy individuals. One thousand one hundred and ten mRNAs were differentially expressed >2-fold throughout terminal granulopoiesis. Major changes were seen in pathways involved in apoptosis, cytokine signaling, and TLR pathways. In addition, G-CSF treatment reduced the levels of four of five measured granule proteins in mature neutrophils, including the proantibacterial protein hCAP-18, which was completely deficient in neutrophils from G-CSF-treated donors. These results indicate that multiple biological processes are altered to satisfy the increased demand for neutrophils during G-CSF-induced emergency granulopoiesis in humans.

Short-term side effects and attitudes towards second donation: A comparison of related and unrelated haematopoietic stem cell donors.

The Nordic Register of Haematopoietic Stem Cell Donors (NRHSD) has registered related and unrelated donors from 10 transplant centres in Sweden, Norway, Finland and Denmark since 1998. We present a prospective, observational study of 1,957 donors, focusing mainly on the differences between related and unrelated donors. Related donors are reported to have more comorbidities, but similar side effects compared with unrelated donors. Side effects after BM or PBSC donation are generally of short duration and in this study no deaths, myocardial infarctions, splenic ruptures, or thromboembolic events are reported. Interestingly, related donors express more hesitancy towards donating again when asked 1 month after donation.

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.

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.

Low-molecular-weight carbohydrate Pentaisomaltose may replace dimethyl sulfoxide as a safer cryoprotectant for cryopreservation of peripheral blood stem cells.

BACKGROUND: Cryopreserved hematopoietic stem cell products are widely used for certain hematologic malignancies. Dimethyl sulfoxide (DMSO) is the most widely used cryoprotective agent (CPA) today, but due to indications of cellular toxicity, changes of the cellular epigenetic state, and patient-related side effects, there is an increasing demand for DMSO-free alternatives. We therefore investigated whether Pentaisomaltose (PIM), a low-molecular-weight carbohydrate (1 kDa), can be used for cryopreservation of peripheral blood stem cells, more specifically hematopoietic progenitor cell apheresis (HPC(A)) product. STUDY DESIGN AND METHODS: We cryopreserved patient or donor HPC(A) products using 10% DMSO or 16% PIM and quantified the recovery of CD34+ cells and CD34+ subpopulations by multicolor flow cytometry. In addition, we compared the frequency of HPCs after DMSO and PIM cryopreservation using the colony-forming cells (CFCs) assay. RESULTS: The mean CD34+ cell recovery was 56.3 ± 23.7% (11.4%-97.3%) and 58.2 ± 10.0% (45.7%-76.9%) for 10% DMSO and 16% PIM, respectively. The distribution of CD34+ cell subpopulations was similar when comparing DMSO or PIM as CPA. CFC assay showed mean colony numbers of 70.7 ± 25.4 (range, 37.8-115.5) and 67.7 ± 15.7 (range, 48-86) for 10% DMSO and 16% PIM, respectively. CONCLUSION: Our findings demonstrate that PIM cryopreservation of HPC(A) products provides recovery of CD34+ cells, CD34+ subpopulations, and CFCs similar to that of DMSO cryopreservation and therefore may have the potential to be used for cryopreservation of peripheral blood stem cells.

Bone marrow-derived mesenchymal stromal cell treatment in patients with severe ischaemic heart failure: a randomized placebo-controlled trial (MSC-HF trial).

AIMS: Regenerative treatment with mesenchymal stromal cells (MSCs) has been promising in patients with ischaemic heart failure but needs confirmation in larger randomized trials. We aimed to study effects of intra-myocardial autologous bone marrow-derived MSC treatment in patients with severe ischaemic heart failure. METHODS AND RESULTS: The MSC-HF trial is a randomized, double-blind, placebo-controlled trial. Patients were randomized 2 : 1 to intra-myocardial injections of MSC or placebo, respectively. The primary endpoint was change in left ventricular end-systolic volume (LVESV), measured by magnetic resonance imaging or computed tomography at 6 months follow-up. Sixty patients aged 30-80 years with severe ischaemic heart failure, New York Heart Association (NYHA) classes II-III, left ventricular ejection fraction (LVEF) <45% and no further treatment options were randomized. Fifty-five patients completed the 6-month follow-up (37 MSCs vs. 18 placebo). At 6 months, LVESV was reduced in the MSC group: -7.6 (95% CI -11.8 to -3.4) mL (P = 0.001), and increased in the placebo group: 5.4 (95% CI -0.4 to 11.2) mL (P = 0.07). The difference between groups was 13.0 (95% CI 5.9-20.1) mL (P = 0.001). Compared with placebo, there were also significant improvements in LVEF of 6.2% (P<0.0001), stroke volume of 18.4 mL (P < 0.0001), and myocardial mass of 5.7 g (P = 0.001). No differences were found in NYHA class, 6-min walking test and Kansas City cardiomyopathy questionnaire. No side effects were identified. CONCLUSION: Intra-myocardial injections of autologous culture expanded MSCs were safe and improved myocardial function in patients with severe ischaemic heart failure. STUDY REGISTRATION NUMBER: NCT00644410 (ClinicalTrials.gov).

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.

Addition of plerixafor for CD34+ cell mobilization in six healthy stem cell donors ensured satisfactory grafts for transplantation.

BACKGROUND: In allogeneic hematopoietic stem cell (HSC) transplantation, collection of a sufficient number of HSCs at a fixed time point is crucial. For HSC mobilization into the peripheral blood, the standard regimen, that is, granulocyte-colony-stimulating factor (G-CSF), may be inadequate. Use of plerixafor as adjuvant to G-CSF is so far off-label in healthy donors. STUDY DESIGN AND METHODS: We present six cases in which the "just-in-time" addition of plerixafor ensured proper CD34+ collection from healthy donors with insufficient G-CSF mobilization. In four of these cases a high number of CD34+ cells was needed due to subsequent CD34+ selection or haploidentical transplantation. RESULTS: From all six donors a sufficient number of CD34+ cells was obtained by using plerixafor as an adjuvant to G-CSF. This treatment regimen resulted in only mild side effects for the donor. CONCLUSION: We have presented six cases with different causes leading to insufficient G-CSF mobilization in allogeneic donors and in which the administration of plerixafor just-in-time ensured a proper graft for transplantation.

Mesenchymal Stromal/Stem Cell Therapy Improves Salivary Flow Rate in Radiation-Induced Salivary Gland Hypofunction in Preclinical in vivo Models: A Systematic Review and Meta-Analysis.

BACKGROUND: Mesenchymal stromal/stem cells (MSCs) have been suggested for salivary gland (SG) restoration following radio-induced salivary gland damage. This study aimed to determine the safety and effectiveness of MSC therapy on radio-induced SG damage and hypofunction in preclinical in vivo studies. METHODS: PubMed and EMBASE were systematically searched for preclinical in vivo interventional studies evaluating efficacy and safety of MSC treatment following radio-induced salivary gland damage published before 10th of January 2022. The primary endpoint was salivary flow rate (SFR) evaluated in a meta-analysis. The study protocol was published and registered on PROSPERO ( www.crd.ac.uk/prospero ), registration number CRD42021227336. RESULTS: A total of 16 preclinical in vivo studies were included for qualitative analysis (858 experimental animals) and 13 in the meta-analysis (404 experimental animals). MSCs originated from bone marrow (four studies), adipose tissue (10 studies) and salivary gland tissue (two studies) and were administered intravenously (three studies), intra-glandularly (11 studies) or subcutaneously (one study). No serious adverse events were reported. The overall effect on SFR was significantly increased with a standardized mean difference (SMD) of 6.99 (95% CI: 2.55-11.42). Studies reported improvements in acinar tissue, vascular areas and paracrine factors. CONCLUSION: In conclusion, this systematic review and meta-analysis showed a significant effect of MSC therapy for restoring SG functioning and regenerating SG tissue following radiotherapy in preclinical in vivo studies without serious adverse events. MSC therapy holds significant therapeutic potential in the treatment of radio-induced xerostomia, but comprehensive, randomized, clinical trials in humans are required to ascertain their efficacy in a clinical setting.

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 Dulbecco's modified Eagle's 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.