Aging of mesenchymal stem cell in vitro

BACKGROUND: A hot new topic in medical treatment is the use of mesenchymal stem cells (MSC) in therapy. The low frequency of this subpopulation of stem cells in bone marrow (BM) necessitates their in vitro expansion prior to clinical use. We evaluated the effect of long term culture on the senescence of these cells. RESULTS: The mean long term culture was 118 days and the mean passage number was 9. The average number of PD decreased from 7.7 to 1.2 in the 10th passage. The mean telomere length decreased from 9.19 Kbp to 8.7 kbp in the 9th passage. Differentiation potential dropped from the 6th passage on. The culture's morphological abnormalities were typical of the Hayflick model of cellular aging. CONCLUSION: We believe that MSC enter senescence almost undetectably from the moment of in vitro culturing. Simultaneously these cells are losing their stem cell characteristics. Therefore, it is much better to consider them for cell and gene therapy early on

Donor Variability in Growth Kinetics of Healthy hMSCs Using Manual Processing:Considerations for Manufacture of Cell Therapies

Human mesenchymal stromal cells (hMSCs) are excellent candidates for cell therapy but their expansion to desired clinical quantities can be compromised by ex vivo processing, due to differences between donor material and process variation. The aim of this article is to characterize growth kinetics of healthy baseline "reference" hMSCs using typical manual processing. Bone-marrow derived hMSCs from ten donors are isolated based on plastic adherence, expanded, and analyzed for their growth kinetics until passage 4. Results indicate that hMSC density decreases with overall time in culture (p < 0.001) but no significant differences are observed between successive passages after passage 1. In addition, fold increase in cell number dropped between passage 1 and 2 for three batches, which correlated to lower performance in total fold increase and expansion potential of these batches, suggesting that proliferative ability of hMSCs can be predicted at an early stage. An indicative bounded operating window is determined between passage 1 and 3 (PDL < 10), despite the high inter-donor variability present under standardized hMSC expansion conditions used. hMSC growth profile analysis will be of benefit to cell therapy manufacturing as a tool to predict culture performance and attainment of clinically-relevant yields, therefore stratifying the patient population based on early observation

Ankylosing Spondylitis and Mesenchymal Stromal/Stem Cell Therapy: A New Therapeutic Approach

Ankylosing spondylitis (AS) is an inflammatory rheumatoid disease categorized within spondyloarthropathies (SpA) and manifested by chronic spinal arthritis. Several innate and adaptive immune cells and secreted-mediators have been indicated to play a role in AS pathogenesis. Considering the limitations of current therapeutic approaches (NSAIDs, glucocorticoids, DMARDs and biologic drugs), finding new treatments with fewer side effects and high therapeutic potentials are required in AS. Mesenchymal stem cells (MSCs) with considerable immunomodulatory and regenerative properties could be able to attenuate the inflammatory responses and help tissue repair by cell-to-cell contact and secretion of soluble factors. Moreover, MSCs do not express HLA-DR, which renders them a favorable therapeutic choice for transplantation in immune-mediated disorders. In the present review, we describe immunopathogenesis and current treatments restrictions of AS. Afterwards, immunomodulatory properties and applications of MSCs in immune-mediated disorders, as well as recent findings of clinical trials involving mesenchymal stem cell therapy (MSCT) in ankylosing spondylitis, will be discussed in detail. Additional studies are required to investigate several features of MSCT such as cell origin, dosage, administration route and, specifically, the most suitable stage of disease for ideal intervention