Isolation of Multipotent Mesenchymal Stromal Cells from Cryopreserved Human Umbilical Cord Tissue

Long-term cryopreservation of whole gingival tissue

Stem cells obtained from the body tissue, such as adipose tissue, dental pulp and gingival tissue. Fresh tissue is often used to isolate and culture for regenerative medicine. However, availability of tissue as and when required is one of the measure issue in regenerative medicine. Cryopreservation of tissue provides benefit over tissue availability, storage for significant amount of period and helps preserve the original cell structures. The effects of cryopreservation of gingival tissue for mesenchymal stem cell (MSC) are not well documented; however this process is of increasing importance for regenerative therapies. This study examined the effect of cryopreservation on the long term survival the whole gingival biopsy tissue. We studied cell outgrowth, cell morphology, MSC surface-markers and differentiation of mesenchymal stem cells derived from cryopreserved gingiva. In this study, gingival tissue was cryopreserved for 3, 6, 9 months. Cryopreserved tissue has been thawed and cells were isolated by using explant culture method. The fresh and cryopreserved gingival tissue cells were cultured and characterized for surface marker analysis, CFU-f, population doubling time, and osteogenic, chondrogenic and adipogenic differentiation. The fresh and cryopreserved tissue has similar stem cell properties. Results indicate that cryopreservation of the entire gingival tissue does not affect the properties of stem cells. This opens door for gingival tissue banking for future use in periodontology and regenerative medicine.

Optimisation of processing methods to improve success in the derivation of human multipotent mesenchymal stromal cells from cryopreserved umbilical cord tissue fragments

Wharton's Jelly (WJ)-derived Mesenchymal Stromal Cells (MSC) are currently in the spotlight for the development of innovative MSC-based therapies due to their ease of sourcing, high proliferation capacity and improved immunopotency over MSC from other tissue sources. However, the short time window for derivation from donated fresh umbilical cord (UC) tissue fragments does not allow to consider biological features of the donor beyond serological safety testing. This limits the scope of MSC banking to rapid, prospective derivation of MSC, WJ lines without considering biological and genetic characteristics of the donor that may influence their suitability for clinical use (e.g. HLA type, inherited gene variants). In the present study, we describe a simple, efficient and reproducible approach for the cryopreservation of UC tissue fragments, compatible with established workflows in existing public frameworks for cord blood and tissue collection while guaranteeing pharmaceutical grade of starting materials for further processing under GMP standards. Herein we demonstrated the feasibility of time and cost-saving methods for cryopreservation of unprocessed UC tissue fragments directly at reception of the donated tissues using 10% Me₂SO-based cryosolution and a commercial clinical-grade defined cryopreservation medium (Cryostor®), showing the preservation of all Critical Quality Attributes in terms of identity, potency and kinetic parameters. In summary, our study provides evidence that cryopreservation of large unprocessed UC tissue fragments (5-13.5 cm) supports subsequent progenitor cell isolation and derivation of MSC,WJ, preserving their viability, identity, proliferation rates and potency.

Human Umbilical Cord Tissue-Derived Multipotent Mesenchymal Stromal Cells Exhibit Maximum Secretory Activity in the Presence of Umbilical Cord Blood Serum

Using multiplex analysis, we performed a comparative study of cytokine and growth factor production by human umbilical cord tissue-derived multipotent mesenchymal stromal cells (UC-MSC) cultured under standard conditions and in the presence of human umbilical cord blood serum (UCBS). It was found that the secretion of most studied molecules, including well-known inductors of regeneration HGF, G-CSF, GM-CSF, and VEGF by UCMSC considerably increased in the presence of 5% UCBS. The use of UCBS allows not only obtaining xenogenic-free cellular and cell-free therapeutic products, but also increasing the secretion of most biologically active molecules capable of stimulating repair processes.

Human Umbilical Cord Blood Serum/Plasma: Cytokine Profile and Prospective Application in Regenerative Medicine

The concentrations of cytokines and growth factors in human umbilical cord blood serum and plasma samples were measured by multiplex analysis. It was found that in comparison with peripheral blood serum of adult donors, umbilical cord blood serum and plasma contain significantly higher concentrations of the most studied molecules including IL-4, 5, 6, 7, 10 and 15, MCP-1, SCF, and SDF, as well as growth factors directly involved in the processes of regeneration (G-CSF, HGF, PDGF-BB, and VEGF). Thus, umbilical cord blood plasma and especially serum are a rich source of cytokines and growth factors with anti-inflammatory, anti-apoptotic, and angiogenic effects and can be used in various fields of regenerative medicine.

Effect of Storage Conditions on the Integrity of Human Umbilical Cord Mesenchymal Stromal Cell-Derived Microvesicles

We studied the effect of storage conditions on the safety of microvesicles produced by human multipotent umbilical cord mesenchymal stromal cells into the conditioned medium. It was found that microvesicles can be stored without serious degradation for up to 1 week at 4°С, but were almost completely destroyed during freezing and thawing cycles irrespective of the storage temperatures (-20°С, -70°С, or -196°С). Similar results were obtained for lyophilized medium conditioned by human multipotent umbilical cord mesenchymal stromal cells. Addition of a cryoprotectant (5-10% DMSO) followed by freezing and/or lyophilization preserved microvesicles at a nearly initial level. These findings indicate that during storage, microvesicles, being membrane structures, behave similar to living cells and require appropriate conditions for prolonged storage.

Comparative Analysis of Secretome of Human Umbilical Cord- and Bone Marrow-Derived Multipotent Mesenchymal Stromal Cells

Production of cytokines and growth factors by cultured human umbilical cord tissue- and bone marrow-derived multipotent mesenchymal stromal cells was measured by multiplex analysis. In most cases, the concentrations of bioactive factors in the culture medium conditioned by umbilical cord-derived cells was ten- to hundred-times higher than in the medium conditioned by bone marrow-derived cells. These results suggest that both multipotent mesenchymal stromal cells from the umbilical cord and cell-free products can have more pronounced therapeutic effect in comparison with mesenchymal stromal cells obtained from "adult" sources.

DMSO-Free Cryopreservation of Human Umbilical Cord Tissue

Human umbilical cord represents a source of multipotent stromal cells of a supreme therapeutic potential. The cells can be isolated from either fresh or cryopreserved umbilical cord tissues. DMSO is a cryoprotectant most commonly used for preservation of umbilical cord tissues; however, cyto- and genotoxicity of this compound is evident and well documented. In the present study we performed successful cryopreservation of the umbilical cord tissue using other cryoprotectants: propylene glycol, ethylene glycol, and glycerol. Of these, 1.5 M ethylene glycol and 20% glycerol turned out to be the best in terms of the preservation of living cells within the frozen tissue, early onset of migration of these cells out of the thawed explants, and overall efficacy of multipotent stromal cell isolation. Cryobanking of tissues can improve availability of multiple cell products for medical purposes and promote the development of personalized medicine.

Umbilical cord tissue cryopreservation: a short review

In this review we present current evidence on the possibility of umbilical cord tissue cryopreservation for subsequent clinical use. Protocols for obtaining umbilical cord-derived vessels, Wharton’s jelly-based grafts, multipotent stromal cells, and other biomedical products from cryopreserved umbilical cords are highlighted, and their prospective clinical applications are discussed. Examination of recent literature indicates we should expect high demand for cryopreservation of umbilical cord tissues in the near future.

Nicotine-enhanced stemness and epithelial-mesenchymal transition of human umbilical cord mesenchymal stem cells promote tumor formation and growth in nude mice

Cigarette smoking is a well-known risk factor in the development and progression of malignant diseases. Nicotine, the major constituent in cigarette smoke, has also shown negative effects on stem cells. Mesenchymal stem cells (MSCs) have been widely demonstrated to migrate into tumors and play key roles in cancer progression. However, the mechanisms by which nicotine impacts MSCs and tumorigenesis of lung cancer are still undetermined. In this study we investigated the effects of nicotine on human umbilical cord mesenchymal stem cells (hUC-MSCs) and the impacts of nicotine-treated hUC-MSCs on tumor formation and progression. We found that nicotine has a toxic effect on hUC-MSCs and changes the morphology, inhibits proliferation and promotes apoptosis of hUC-MSCs in a dose-dependent manner. Nicotine-treated hUC-MSCs produce higher level of IL-6. Moreover, nicotine promotes migration, stemness and epithelial-mesenchymal transition (EMT) of hUC-MSCs by inhibiting E-cadherin expression and upregulating mesenchymal markers such as N-cadherin and Vimentin, leading to the induction of stem cell markers Sox2, Nanog, Sall4, Oct4 and CD44. Migration and proliferation of non-small cell lung cancer A549 cells and breast cancer MCF-7 cells are promoted after their coculture with nicotine-treated hUC-MSCs in a cell-cell contact-independent manner. Furthermore, nicotine-treated hUC-MSCs promote tumor formation and growth of A549 cells in nude mice. These studies demonstrated that the enhanced stemness and EMT of hUC-MSCs induced by nicotine are critical for the development of tobacco-related cancers.

The Short-Chain Fatty Acid Propionate Inhibits Adipogenic Differentiation of Human Chorion-Derived Mesenchymal Stem Cells Through the Free Fatty Acid Receptor 2

Free fatty acid receptor 2 (FFAR2, also known as GPR43) is a G-protein-coupled receptor activated by short-chain fatty acids that are produced by gut microbiota through fermentation of nondigestible carbohydrates. FFAR2 functions as a metabolic sensor and is expressed in metabolically active tissues, such as adipose tissue. Earlier studies proved the connection between FFAR2 and adipocyte differentiation in mice. The aim of this study was to investigate the implication of FFAR2 receptor in adipogenesis in human chorion-derived mesenchymal stem cells (cMSCs). The short-chain fatty acid, propionate, and phenylacetamide a selective FFAR2 agonist resulted in a marked suppression of lipid droplet accumulation during the adipogenic differentiation of cMSCs. Western blot studies revealed that FFAR2 was detectable at any time point of the differentiation period. The direct involvement of FFAR2 in the differentiation into adipocytes was proven by the downregulation of its gene expression in cMSCs by lentiviral messenger RNA (mRNA) silencing transduction particles. Our results showed that a significant suppression in lipid accumulation upon FFAR2 agonist treatments was elicited by FFAR2-silencing. Based on these results we suggest that propionate inhibits the formation of adipocytes from MSCs and acts on adipogenesis predominantly via FFAR2.

Umbilical Cord-Derived Mesenchymal Stem Cells Relieve Hindlimb Ischemia through Enhancing Angiogenesis in Tree Shrews

Hindlimb ischemia is still a clinical problem with high morbidity and mortality. Patients suffer from consequent rest pain, ulcers, cool limbs, and even amputation. Angiogenesis is a promising target for the treatment of ischemic limbs, providing extra blood for the ischemic region. In the present study, we investigated the role of umbilical cord-derived mesenchymal stem cells (UC-MSCs) in regulating angiogenesis and relieving hindlimb ischemia. UC-MSCs were isolated from the umbilical cord of tree shrews. Angiography results showed that UC-MSCs injection significantly promoted angiogenesis in tree shrews. Moreover, the ankle brachial index, transcutaneous oxygen pressure, blood perfusion, and capillary/muscle fiber ratio were all markedly increased by the application of UC-MSCs. In addition, the conditioned culture of human umbilical vein endothelial cells using medium collected from UC-MSCs showed higher expression of angiogenic markers and improved migration ability. In short, the isolated UC-MSCs notably contributed to restoring blood supply and alleviating the symptoms of limb ischemia through enhancing angiogenesis.