Effects of adipose-derived stem cells on keloid fibroblasts based on paracrine function

Ameliorating Fibrotic Phenotypes of Keloid Dermal Fibroblasts through an Epidermal Growth Factor-Mediated Extracellular Matrix Remodeling

Keloid and hypertrophic scars are skin fibrosis-associated disorders that exhibit an uncontrollable proliferation of fibroblasts and their subsequent contribution to the excessive accumulation of extracellular matrix (ECM) in the dermis. In this study, to elucidate the underlying mechanisms, we investigated the pivotal roles of epidermal growth factor (EGF) in modulating fibrotic phenotypes of keloid and hypertrophic dermal fibroblasts. Our initial findings revealed the molecular signatures of keloid dermal fibroblasts and showed the highest degree of skin fibrosis markers, ECM remodeling, anabolic collagen-cross-linking enzymes, such as lysyl oxidase (LOX) and four LOX-like family enzymes, migration ability, and cell–matrix traction force, at cell–matrix interfaces. Furthermore, we observed significant EGF-mediated downregulation of anabolic collagen-cross-linking enzymes, resulting in amelioration of fibrotic phenotypes and a decrease in cell motility measured according to the cell–matrix traction force. These findings offer insight into the important roles of EGF-mediated cell–matrix interactions at the cell–matrix interface, as well as ECM remodeling. Furthermore, the results suggest their contribution to the reduction of fibrotic phenotypes in keloid dermal fibroblasts, which could lead to the development of therapeutic modalities to prevent or reduce scar tissue formation.

Efficient co-cultivation of human fibroblast cells (HFCs) and adipose-derived stem cells (ADSs) on gelatin/PLCL nanofiber

In this study, we investigated whether the nanofibers produced by natural-synthetic polymers can probably promote the proliferation of co-cultured adipose-derived stem cells/human fibroblast cells (ADSs/HFCs) and synthesis of collagen. Nanofiber was fabricated by blending gelatin and poly (L-lactide co-ɛ-caprolactone) (PLCL) polymer nanofiber (Gel/PLCL). Cell morphology and the interaction between cells and Gel/PLCL nanofiber were evaluated by FESEM and fluorescent microscopy. MTS assay and quantitative real-time polymerase chain reaction were applied to assess the proliferation of co-cultured ADSs/HFCs and the collagen type I and III synthesis, respectively. The concentrations of two cytokines including fibroblast growth factor-basic and transforming growth factor-β1 were also measured in culture medium of co-cultured ADSs/HDCs using enzyme-linked immunosorbent assay assay. Actually, nanofibers exhibited proper structural properties in terms of stability in cell proliferation and toxicity analysis processes. Gel/PLCL nanofiber promoted the growth and the adhesion of HFCs. Our results showed in contact co-culture of ADSs/HFCs on the Gel/PLCL nanofiber increased cellular adhesion and proliferation synergistically compared to non-coated plate. Also, synthesis of collagen and cytokines secretion of co-cultured ADSs/HFCs on Gel/PLCL scaffolds is significantly higher than non-coated plates. To conclude, the results suggest that Gel/PLCL nanofiber can imitate physiological characteristics in vivo and enhance the efficacy of co-cultured ADSs/HFCs in wound healing process.

Optimal Condition of Isolation from an Adipose Tissue-Derived Stromal Vascular Fraction for the Development of Automated Systems

BACKGROUND

The stromal vascular fraction (SVF) isolated from adipose tissue, which contains stem cells as well as other cell types, has been applied in various research fields. Although different enzymatic concentrations and treatment durations have been applied to isolate the SVF, optimal conditions have not been established. Thus, we aimed to establish the optimal conditions for isolation of the SVF from adipose tissue by automated systems.

METHODS

The SVF was collected from removed adipose tissues of five donors during surgery. The SVF was treated with 0.1% or 0.2% collagenase type I for 20, 40, or 60 min. Then, colony forming unit (CFU) assays and flow cytometry were performed to characterize the adipose stem cells (ASCs). A cytokine array was used to investigate the correlation between colony-formation ability and the secretion of isolated ASCs.

RESULTS

Treatment with 0.1% collagenase type I for 60 min resulted in a higher SVF yield, whereas treatment with 0.1% collagenase for 40 min resulted in higher CFU values. In addition, expression of interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1 in the SVF was higher in the high-CFU group than in the low-CFU group.

CONCLUSION

The optimal conditions for isolation of the SVF from adipose tissue were treatment with 0.1% collagenase type I for 40 min. We identified the conditions required for efficient SVF isolation based on high CFU values, and our results will facilitate the development of automated systems.

Extracellular Vesicles in Neurodegenerative Diseases: A Double-Edged Sword

Extracellular vesicles (EVs), a heterogenous group of membrane-bound particles, are virtually secreted by all cells and play important roles in cell-cell communication. Loaded with proteins, mRNAs, non-coding RNAs and membrane lipids from their donor cells, these vesicles participate in normal physiological and pathogenic processes. In addition, these sub-cellular vesicles are implicated in the progression of neurodegenerative disorders. Accumulating evidence suggests that intercellular communication via EVs is responsible for the propagation of key pathogenic proteins involved in the pathogenesis of amyotrophic lateral sclerosis, Parkinson's diseases, Alzheimer's diseases and other neurodegenerative disorders. For therapeutic perspective, EVs present advantage over other synthetic drug delivery systems or cell therapy; ability to cross biological barriers including blood brain barrier (BBB), ability to modulate inflammation and immune responses, stability and longer biodistribution with lack of tumorigenicity. In this review, we summarized the current state of EV research in central nervous system in terms of their values in diagnosis, disease pathology and therapeutic applications.