Redox homeostasis plays a crucial role in the regulation of self-renewal and differentiation of stem cells. However, the behavioral actions of mesenchymal stem cells in redox imbalance state remain elusive. In the present study, the effect of redox imbalance that was induced by either hydrogen peroxide (H2O2) or ascorbic acid on human cardiac-resident (hC-MSCs) and non-resident (umbilical cord) mesenchymal stem cells (hUC-MSCs) was evaluated. Both cells were sensitive and responsive when exposed to either H2O2 or ascorbic acid at a concentration of 400 µmol/L. Ascorbic acid pre-treated cells remarkably ameliorated the reactive oxygen species level when treated with H2O2. The endogenous antioxidative enzyme gene (Sod1, Sod2, TRXR1 and Gpx1) expressions were escalated in both MSCs in response to reactive oxygen species elevation. In contrast, ascorbic acid pre-treated hUC-MSCs attenuated considerable anti-oxidative gene (TRXR1 and Gpx1) expressions, but not the hC-MSCs. Similarly, the cardiogenic gene (Nkx 2.5, Gata4, Mlc2a and β-MHC) and ion-channel gene ( IKDR, IKCa, Ito and INa.TTX) expressions were significantly increased in both MSCs on the oxidative state. On the contrary, reduced environment could not alter the ion-channel gene expression and negatively regulated the cardiogenic gene expressions except for troponin-1 in both cells. In conclusion, redox imbalance potently alters the cardiac-resident and non-resident MSCs stemness, cardiogenic, and ion-channel gene expressions. In comparison with cardiac-resident MSC, non-resident umbilical cord-MSC has great potential to tolerate the redox imbalance and positively respond to cardiac regeneration. Impact statement Human mesenchymal stem cells (h-MSCs) are highly promising candidates for tissue repair in cardiovascular diseases. However, the retention of cells in the infarcted area has been a major challenge due to its poor viability and/or low survival rate after transplantation. The regenerative potential of mesenchymal stem cells (MSCs) repudiate and enter into premature senescence via oxidative stress. Thus, various strategies have been attempted to improve the MSC survival in 'toxic' conditions. Similarly, we investigated the response of cardiac resident MSC (hC-MSCs) and non-resident MSCs against the oxidative stress induced by H2O2. Supplementation of ascorbic acid (AA) into MSCs culture profoundly rescued the stem cells from oxidative stress induced by H2O2. Our data showed that the pre-treatment of AA is able to inhibit the cell death and thus preserving the viability and differentiation potential of MSCs.
Mesenchymal stem cell (MSC) transplant may offer an alternative to liver transplantation in patients with end-stage liver disease. However, its efficacy remains uncertain. MSC was performed on a 50-year-old male with decompensated (Child-Turcotte-Pugh grade C) alcoholic liver cirrhosis due to an absence of donors for adult-deceased and living-related liver transplantation. Autologous bone marrow-derived MSCs were harvested from the patient and cultured using standard protocols. The MSCs were subsequently re-administrated into the liver via hepatic intra-arterial infusion on two separate occasions. After infusion, there was an improvement in biochemical parameters (serum total bilirubin, serum albumin), and a reduction of diuretic use for ascites for up to 8 weeks. However, all biochemical and clinical parameters deteriorated on long-term follow-up without any further infusions. The patient eventually succumbed to his disease. MSC transplantation may have a clinical benefit on adult patients with end-stage liver cirrhosis, but this appears to be transitory.
Immune cell-based therapies using natural killer (NK) cells and cytotoxic T cells are under constant scrutiny, with the aim to design an effective and reduced-toxicity therapy, which will benefit patients via improved quality of life and improved prognosis. Four patients with stage IV colon cancer were administered 1, 3, 5 and 6 effector cell intravenous infusions, respectively. Peripheral blood was collected from the patients and the ex vivo activation and expansion of NK and T cells was performed in Good Manufacturing Practice-certified clean rooms for ~12-15 days. Immunophenotypic analysis of the peripheral blood mononuclear cells (PBMCs) and expanded NK and T cells was conducted using flow cytometry and the patients were followed up. On average, 4.8×107 initial PBMCs and 2.7×109 total expanded cells were obtained. The intravenous infusions of the expanded cells were not accompanied by adverse reactions. Improved prognosis, reflected by a considerable decrease in the cancer markers, accompanied by an improved quality of life in the patients were observed. In conclusion, potential strategies are currently under development for the large-scale production of effectors cells; therefore, autologous immune enhancement therapy (AIET) may be considered as a viable approach to cancer treatment.
Despite the surgical and other insertional interventions, the complete recuperation of myocardial disorders is still elusive due to the insufficiency of functioning myocardiocytes. Thus, the use of stem cells to regenerate the affected region of heart becomes a prime important. In line with this human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have gained considerable interest due to their potential use for mesodermal cell based replacement therapy and tissue engineering. Since MSCs are harvested from various organs and anatomical locations of same organism, thus the cardiac regenerative potential of human cardiac-derived MSCs (hC-MSCs) and human umbilical cord Wharton's Jelly derived MSC (hUC-MSCs) were tested concurrently. At in vitro culture, both hUC-MSCs and hC-MSCs assumed spindle shape morphology with expression of typical MSC markers namely CD105, CD73, CD90 and CD44. Although, hUC-MSCs and hC-MSCs are identical in term of morphology and immunophenotype, yet hUC-MSCs harbored a higher cell growth as compared to the hC-MSCs. The inherent cardiac regenerative potential of both cells were further investigated with mRNA expression of ion channels. The RT-PCR results demonstrated that both MSCs were expressing a notable level of delayed rectifier-like K(+) current (I KDR ) ion channel, yet the relative expression level was considerably varied between hUC-MSCs and hC-MSCs that Kv1.1(39 ± 0.6 vs 31 ± 0.8), Kv2.1 (6 ± 0.2 vs 21 ± 0.12), Kv1.5 (7.4 ± 0.1 vs 6.8 ± 0.06) and Kv7.3 (27 ± 0.8 vs 13.8 ± 0.6). Similarly, the Ca2(+)-activated K(+) current (I KCa ) channel encoding gene, transient outward K(+) current (I to ) and TTX-sensitive transient inward sodium current (I Na.TTX ) encoding gene (Kv4.2, Kv4.3 and hNE-Na) expressions were detected in both groups as well. Despite the morphological and phenotypical similarity, the present study also confirms the existence of multiple functional ion channel currents IKDR, IKCa, Ito, and INa.TTX in undifferentiated hUC-MSCs as of hC-MSCs. Thus, the hUC-MSCs can be exploited as a potential candidate for future cardiac regeneration.
Age-associated changes in natural killer (NK) cell population, phenotype, and functions are directly attributed to the risk of several diseases and infections. It is predicted to be the major cause of the increase in mortality. Based on the surface density of CD56, NK cells are subdivided into two types, such as CD56bright and CD56dim cells, which represent cytokine production and cytotoxicity. In our study, we have examined the age-associated changes in the NK cell population and their subsets at different age groups of males and females (at a range from 41 to 80 years). We found that the total lymphocyte count significantly dropped upon aging in both genders. Although, the level of total immune cells also dropped on aging, and surprisingly the total NK cell population was remarkably increased with the majority of NK cells being CD56dim. Subsequently, we evaluated the proliferation potential of NK cells and our results showed that the NK cell proliferation ability declines with age. Overall, our findings prove that there is an increase in the circulating NK cell population upon aging. However, the proliferation rate upon aging declines when compared to the young age group (<41 yrs).