Safety and Potential Effect of Intrauterine Infusion of Autologous Adipose Tissue-Derived Regenerative Cells in Patients With Implantation Failure: A Pilot Study

BACKGROUND

Implantation failure due to thin endometrium has emerged as a major cause of infertility. In this study, we aimed to assess the safety and preliminary efficacy of adipose tissue-derived regenerative cells (ADRCs), a source of adipose-derived stem cells, in infertility patients with implantation failure.

METHODS

Five infertile women with implantation failure despite artificial reproductive technology were enrolled in this study and treated with ADRCs via the intrauterine route. The primary outcome was the incidence of adverse events. Additional outcomes were endometrial thickness after ADRC treatment and pregnancy success after embryo transfer.

RESULTS

There were no adverse events in any patient. There was no elevation of white blood cell count, C-reactive protein, or D-dimer levels. There was a significant difference in endometrial thickness in the secretory phase before versus after intrauterine transplantation of ADRCs (3.8 ± 1.3 mm versus 8.8 ± 2.8 mm, respectively; p<0.05). A gestational sac and fetal heartbeat were detected on transvaginal ultrasound in two of five patients.

CONCLUSION

Intrauterine infusion of autologous ADRCs is a simple and safe procedure that may ameliorate the endometrial microenvironment in infertile women with implantation failure.

Effects of Sepsis Serum on the Fate of Adipose Tissue-Derived Stem Cells

BACKGROUND

Adipose tissue-derived stem cells (ADSCs), a type of mesenchymal stem cell, have been used extensively in clinical trials for the treatment of multiple conditions, including sepsis. However, increasing evidence indicates that ADSCs vanish from tissues within days of administration. Consequently, it would be desirable to establish the mechanisms underlying the fate of ADSCs following transplantation.

METHODS

In this study, sepsis serum from mouse models was used to mimic microenvironmental effects. Healthy donor-derived human ADSCs were cultured in vitro in the presence of mouse serum from normal or lipopolysaccharide (LPS)-induced sepsis models for the purposes of discriminant analysis. The effects of sepsis serum on ADSC surface markers and cell differentiation were analyzed by flow cytometry, and the proliferation of ADSCs was assessed using a Cell Counting Kit-8 (CCK-8) assay. Quantitative real-time PCR (qRT-PCR) was applied to assess the degree of ADSC differentiation. The effects of sepsis serum on the cytokine release and migration of ADSCs were determined based on ELISA and Transwell assays, respectively, and ADSC senescence was assessed by β-galactosidase staining and western blotting. Furthermore, we performed metabolic profiling to determine the rates of extracellular acidification and oxidative phosphorylation and the production of adenosine triphosphate and reactive oxygen species.

RESULTS

We found that sepsis serum enhanced the cytokine and growth factor secretion and migratory capacities of ADSCs. Moreover, the metabolic pattern of these cells was reprogrammed to a more activated oxidative phosphorylation stage, leading to an increase in osteoblastic differentiation capacity and reductions in adipogenesis and chondrogenesis.

CONCLUSIONS

Our findings in this study reveal that a septic microenvironment can regulate the fate of ADSCs.

Co-transfection with BMP2 and FGF2 via chitosan nanoparticles potentiates osteogenesis in human adipose-derived stromal cells in vitro

OBJECTIVE

To investigate if co-transfection of human bone morphogenetic protein 2 (BMP-2, BMP2) and human fibroblast growth factor 2 (FGF2, FGF2) via chitosan nanoparticles promotes osteogenesis in human adipose tissue-derived stem cells (ADSCs) in vitro.

MATERIALS AND METHODS

Recombinant BMP2 and/or FGF2 expression vectors were constructed and packaged into chitosan nanoparticles. The chitosan nanoparticles were characterized by atomic force microscopy. Gene and protein expression levels of BMP-2 and FGF2 in ADSCs in vitro were evaluated by real-time polymerase chain reaction (PCR), western blot, and enzyme-linked immunosorbent assay. Osteocalcin (OCN) and bone sialoprotein (BSP) gene expression were also evaluated by real-time PCR to assess osteogenesis.

RESULTS

The prepared chitosan nanoparticles were spherical with a relatively homogenous size distribution. The BMP2 and FGF2 vectors were successfully transfected into ADSCs. BMP-2 and FGF2 mRNA and protein levels were significantly up-regulated in the co-transfection group compared with the control group. OCN and BSP mRNA levels were also significantly increased in the co-transfection group compared with cells transfected with BMP2 or FGF2 alone, suggesting that co-transfection significantly enhanced osteogenesis.

CONCLUSIONS

Co-transfection of human ADSCs with BMP2/FGF2 via chitosan nanoparticles efficiently promotes the osteogenic properties of ADSCs in vitro.

Enhanced expression of cyclooxygenase-2 related multi-drug resistance gene in melanoma and osteosarcoma cell lines by TSG-6 secreted from canine adipose-derived mesenchymal stem/stromal cells

BACKGROUND

Multiple drug resistance (MDR) of cancer cells is the main cause of intrinsic or acquired desensitization to chemotherapy in many cancers. A number of studies have found high expression of COX-2 to be a factor for expression of MDR gene in several cancer. Furthermore, adipose tissue derived mesenchymal stem/stromal cells (ADSC) have been found to increase cyclo-oxygenase-2 (COX-2) expression in some tumour cells. The mechanism for this, however, is not yet clear and needs further study.

OBJECTIVE

The purpose of this study was to determine whether tumour necrosis factor-alpha stimulated gene/protein 6 (TSG-6) secreted from ADSCs is associated with an increase in MDR genes by inducing COX-2 gene expression in melanoma and osteosarcoma cell lines.

METHODS

ADSCs were transfected with TSG-6 siRNA or Control RNA respected, and cancer cell line were transfected with COX-2 siRNA or Control RNA respected. Using trans well coculture system, the interactions of ADSCs with tumour cells were investigated.

RESULTS

Increased COX-2 expression was observed in cancer cell co-cultured with ADSCs. Additionally, we identified that COX-2 expression was related to drug resistance genes (P-glycoprotein, multidrug resistance-associated protein). Transfecting canine ADSCs with small interfering RNA, TSG-6 secreted from ADSCs was found to be a major factor in the regulation of COX-2 expression and drug resistance genes in osteosarcoma and melanoma cell lines.

CONCLUSION

TSG-6 mediated COX-2 up-regulation is a possible mechanism of chemoresistance development induced by ADSCs. These findings provide better understanding about the mechanism associated with ADSC-induced chemoresistance in cancer.

CXCL5 secreted from adipose tissue-derived stem cells promotes cancer cell proliferation

Accumulating data suggest that adipose tissue facilitates breast tumor initiation and progression through paracrine and endocrine pathways, and that adipose tissue-derived stem cell (ASC) is likely the major cell type responsible for tumorigenesis and tumor development. However, it remains unknown how ASCs exert their effects. In the present study, in cultured breast cancer cell lines, including estrogen receptor (ER)-positive MCF-7 cells and ER-negative MDA-MB-231 cells, the effects on tumor proliferation of isolated ASCs from human breasts were examined. The expression of 174 cytokines was additionally identified in this medium. With an anti-human C-X-C motif ligand 5 (CXCL5) monoclonal antibody, the effects of neutralization of CXCL5 on the actions of ASCs in a co-culture medium of ASCs and tumor cells were studied The results demonstrated that ASCs significantly increased the number of breast cancer cells compared with controls. Similarly, the co-culture medium of ASCs with breast cancer cells exhibited potent effects on tumor cell proliferation. In the co-culture medium of ASCs with breast cancer cells, CXCL5 levels were significantly increased. In addition, depletion of CXCL5 with its specific antibody in ASC-conditioned medium blocked the stimulatory effect of ASCs on the proliferation of breast cancer cells. To the best of our knowledge, these results indicate for the first time that ASC-secreted CXCL5 is a key factor promoting breast tumor cell proliferation.

Impact of Polo-like kinase 1 inhibitors on human adipose tissue-derived mesenchymal stem cells

Polo-like kinase 1 (Plk1) has been established as one of the most promising targets for molecular anticancer intervention. In fact, various Plk1 inhibitors have been identified and characterized. While the data derived from the bench are prospective, the clinical outcomes are less encouraging by showing modest efficacy. One of the explanations for this discrepancy could be unintendedly targeting of non-malignant cells by Plk1 inhibitors. In this work, we have addressed the effect of Plk1 inhibition in adipose tissue-derived mesenchymal stem cells (ASCs). We show that both visceral and subcutaneous ASCs display monopolar spindles, reduced viability and strong apoptosis induction upon treatment with BI 2536 and BI 6727, the Plk1 kinase domain inhibitors, and with Poloxin, the regulatory Polo-box domain inhibitor. While Poloxin triggers quickly apoptosis, BI 2536 and BI 6727 result in mitotic arrest in ASCs. Importantly, survived ASCs exhibit DNA damage and a pronounced senescent phenotype. In addition, Plk1 inhibition impairs ASCs' motility and homing ability. These results show that Plk1 inhibitors target slowly proliferating ASCs, an important population of anti-inflammation and immune modulation. The toxic effects on primary cells like ASCs could be partially responsible for the reported moderate antitumor activity in patients treated with Plk1 inhibitors.

Effect of Recombinant Human Bone Morphogenetic Protein-2 and Adipose Tissue-Derived Stem Cell on New Bone Formation in High-Speed Distraction Osteogenesis

PURPOSE

The effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) and osteogenically differentiated adipose tissue-derived stem cells (ADSC) on new bone formation in high-speed distraction osteogenesis of adult rabbit cranium were investigated.

MATERIALS AND METHODS

A total of 41 adult rabbits were used in the study. Distraction began after a 5-day latency period at a rate of 1.5 mm twice a day until 10-mm length gain was obtained both in the control group, where a bone defect was induced, and in the experimental group, in which ADSC (group A), rhBMP-2 (group B), or both (group C) were injected in the distraction gap after distraction. At 4, 8, and 12 weeks after distraction, computed tomography analysis was done to determine the bone defect dimension and bone mineral density (BMD), while histologic examination was also done to calculate bone formation ratio.

RESULTS

Bone defect dimension significantly decreased in groups B and C, compared with the control group, at 4 and 12 weeks after distraction. BMD was significantly increased in groups B and C at 4 weeks. On histologic examination, bone formation ratio was significantly increased in group C only at 12 weeks.

CONCLUSION

This study suggests that the use of rhBMP-2 in combination with or without ADSC is helpful to promote bone regeneration in high-speed distraction osteogenesi s of adult rabbit cranium.