Human Wharton’s Jelly Mesenchymal Stem Cells Plasticity Augments Scar-Free Skin Wound Healing with Hair Growth

<div><p>Human mesenchymal stem cells (MSCs) are a promising candidate for cell-based transplantation and regenerative medicine therapies. Thus in the present study Wharton’s Jelly Mesenchymal Stem Cells (WJ-MSCs) have been derived from extra embryonic umbilical cord matrix following removal of both arteries and vein. Also, to overcome the clinical limitations posed by fetal bovine serum (FBS) supplementation because of xenogeneic origin of FBS, usual FBS cell culture supplement has been replaced with human platelet lysate (HPL). Apart from general characteristic features of bone marrow-derived MSCs, wharton jelly-derived MSCs have the ability to maintain phenotypic attributes, cell growth kinetics, cell cycle pattern, <i>in vitro</i> multilineage differentiation plasticity, apoptotic pattern, normal karyotype-like intrinsic mesenchymal stem cell properties in long-term <i>in vitro</i> cultures. Moreover, the WJ-MSCs exhibited the <i>in vitro</i> multilineage differentiation capacity by giving rise to differentiated cells of not only mesodermal lineage but also to the cells of ectodermal and endodermal lineage. Also, WJ-MSC did not present any aberrant cell state upon <i>in vivo</i> transplantation in SCID mice and <i>in vitro</i> soft agar assays. The immunomodulatory potential assessed by gene expression levels of immunomodulatory factors upon exposure to inflammatory cytokines in the fetal WJ-MSCs was relatively higher compared to adult bone marrow-derived MSCs. WJ-MSCs seeded on decellularized amniotic membrane scaffold transplantation on the skin injury of SCID mice model demonstrates that combination of WJ-MSCs and decellularized amniotic membrane scaffold exhibited significantly better wound-healing capabilities, having reduced scar formation with hair growth and improved biomechanical properties of regenerated skin compared to WJ-MSCs alone. Further, our experimental data indicate that indocyanin green (ICG) at optimal concentration can be resourcefully used for labeling of stem cells and <i>in vivo</i> tracking by near infrared fluorescence non-invasive live cell imaging of labelled transplanted cells, thus proving its utility for therapeutic applications.</p></div

Isolation and primary characterization of WJ-MSCs.

<p>(A) WJ-MSCs Passage 5 in HPL; (B) WJ-MSCs masson’s trichrome staining; (C) Adipocyte differentiation of WJ-MSCs; (D) Oil Red O Staining; Osteocyte differentiation, Von kossa Staining (E) and Alkaline Phosphatase staining (F); (G) Chondrocyte Differentiation, Safranin O Staining; (H) Flow cytometry Analysis of WJ-MSCs; (I) Neural Differentiation, Neuroglia2 immunostaining (J); (K) Smooth muscle actin staining; (L) Photoreceptor cell differentiation, Rhodopsin staining (M); (N) Pancreatic Progenitor differentiation, (O) Insulin, (P) PDX1.</p

Mice skin injury model and <i>in vivo</i> tracking of cells.

<p>(A) Dermal injury; (B) Amniotic membrane containing WJ-MSCs grafting; Area of injury after 14 days, (C) Control, (D) WJ-MSCs injection, (E) Amniotic membrane + WJ-MSCs; H&E staining, (F) Control, (G) WJ-MSCs injection, (H) Amniotic membrane + WJ-MSCs; <i>in vitro</i> analysis of ICG, (I) 2D, (J) 3D; (K) Total flux of ICG in different concentration; (L) GFP labeled WJ-MSCs seeded on amniotic membrane, (i) Phase contrast, (ii) fluorescent image and (iii) merged image. (M) IVIS image of amniotic membrane containing ICG labeled WJ-MSCs grafted mice showing fluorescence for 11 days, (N) decrease in total flux of ICG with passage of time; (O) Singer score of regenerated tissue.</p

Novel nano-composite hydrogels with honey effective against multi-resistant clinical strains of Acinetobacter baumannii and Pseudomonas aeruginosa

Novel alginate hydrogels with silver nanoparticles (AgNPs) and honey components were produced with the aim to target multidrug-resistant bacterial strains causing nosocomial wound infections. AgNP synthesis was optimized in highly concentrated honey solutions so that a 5-month stable, colloid solution with 50% of honey and similar to 8 nm AgNPs at neutral pH was obtained. The colloid solution was further used to produce nano-composite Ag/alginate hydrogels in different forms (microbeads, microfibers and discs) that retained all AgNPs and high fractions of honey components (40-60%) as determined by the phenol-sulfuric acid and Folin-Ciocalteu methods. The hydrogels were characterized by UV-Vis spectroscopy and Fourier-transform infrared-attenuated total reflectance spectroscopy while the antibacterial activity was investigated against a broad spectrum of Gram-negative and Gram-positive bacteria, including 13 multi-resistant clinical strains of Acinetobacter baumannii, one clinical strain of Pseudomonas aeruginosa and one clinical strain of Staphylococcus aureus. At the total released silver concentration of similar to 9 mu g/ml, the hydrogels exhibited strong bactericidal activity against standard and most of the investigated multi-resistant hospital strains with the exemption of 3 clinical strains of A. baumannii in which antibacterial effects were absent. These results reveal the need for further in-depth studies of bacterial resistance mechanisms and, in the same time, potentials of the novel Ag/alginate hydrogels with honey components to combat wound infections and enhance healing as non-sticky, antibacterial, and bioactive dressings