The Role of Microenvironment in Preserving the Potency of Adult Porcine Pulmonary Valve Stem Cells In Vitro

Abstract

Background and ObjectiveThe potency of tissue resident stem cells is regulated primarily by inputs from the local microenvironment. Isolation of stem cells through enzymatic digestion of tissue may affect epigenetic regulation of cell fate and performance. Here we employ a non-enzymatic method to harvest and investigate tissue resident stem cells from the adult porcine pulmonary valve.Methods and ResultsThe presence of c-Kit+ stem cells within the valve tissue was confirmed by immunohistochemistry. An in vitro culture of minced valve leaflets was developed under the standard conditions (37°C with 5% CO2). The viability of the cellular outgrowths was evaluated over the subsequent 12 weeks. Under this culture condition, we identified a population of non-adherent c-Kit+ cells and multiple cellular structures mimicking the phenotype of embryonic stem cells at different stages of development. Formation of multinucleated cells through cell fusion provided an active niche area for homing and interaction of the non-adherent c-Kit+ cells. Expression of pluripotency markers Oct-4 and Nanog was detected in the newly formed multinucleated cells but not in mature colonies. Partial cell fusion was shown by fluorescent live-cell tracking, which confirmed intercellular molecular exchange between donor and recipient cells, resulting in altered cytoplasmic protein expression by the recipient cell.ConclusionsThese results suggest a role for the microenvironment in decrypting the potential of the valve somatic stem cells in vitro. In addition, our data provide evidence for cell fusion, which may play a critical role in reversing somatic cell fate and spontaneous cellular reprogramming.

Fructose vs. Glucose: Modulating Stem Cell Growth and Function Through Sugar Supplementation

“…They greatly vary not only in their origins but also in their potency 6 . This can be attributed partially to the special microenvironment surrounding them that contains the required nutrient, oxygen level, and cytokines suitable for survival and differentiation 4,6 . Any change in the pericellular environment will consequently modulate cell signals, cytokines, that will act directly on the cell itself (autocrine effect) or neighboring cells (paracrine effect) 3,4,6 .…”

“…Our bodies contain various types of stem cells that play a vital role in tissue regeneration and wound healing 45,46 . They greatly vary not only in their origins but also in their potency 6 . This can be attributed partially to the special microenvironment surrounding them that contains the required nutrient, oxygen level, and cytokines suitable for survival and differentiation 4,6 .…”

“…However, the acessibility of these resources in the pericellular environment greatly varies from organ to organ 3–5 . This divergence in resource availability leads to variations in the potency and differentiation potential of stem cells 4,6 . Moreover, hexose and oxygen levels modulate cytokine production which is crucial for cell-cell communication 7,8 as well as growth, and differentiation of stem cell 9,10 . Hence, this study aims to explore the distinct effects of glucose and fructose, as well as different oxygen tensions, on the growth dynamics, cytokine production, and differentiation of stem cells.…”

Fructose vs. glucose: modulating stem cell growth and function through sugar supplementation

“…Stem cells play a vital role in tissue regeneration and wound healing [49,50]. They greatly vary not only in their origins but also in their potency [51]. This can be attributed partially to the special microenvironment surrounding them that contains the required nutrient, oxygen level, and cytokines suitable for survival and differentiation [51,52].…”

“…They greatly vary not only in their origins but also in their potency [51]. This can be attributed partially to the special microenvironment surrounding them that contains the required nutrient, oxygen level, and cytokines suitable for survival and differentiation [51,52]. Any change in the pericellular environment will consequently modulate cell signals, cytokines, that will act directly on the cell itself (autocrine effect) or neighboring cells (paracrine effect) [51–53].…”