Independent thesis Advanced level (professional degree), 20 credits / 30 HE credits
Abstract
Background
Mesenchymal stem cells (MSC) are non-hematopoietic multipotent stromal cells that can differentiate into lineages such as adipocytes, osteocytes and chondrocytes. MSC are immune privileged and also possess immunosuppressive properties, which in combination with their differentiative properties makes them excellent candidates for tissue engineering, an alternative treatment solution for of congenital malformations. This study will investigate mesenchymal stem cells from amniotic fluid and umbilical cords to evaluate which tissue that is superior for tissue engineering.
Methods and Results
Mesenchymal stem cells were isolated from amniotic fluid (afMSC) obtained at routinely performed amniocenteses and from umbilical cords (ucMSC) collected at births from elective caesarean sections. afMSC were cultured in Dulbecco’s modified Eagle medium-low glucose (DMEM) and ucMSC isolated with 3 different protocols were cultured in two different media; modified Eagle medium Alpha (MEMα) and DMEM.
After expansion, the cell populations were characterized in regards to their phenotype, immunological properties, proliferative capacity and in vitro differentiation abilities.
Mixed lymphocytes culture (MLC) showed that the af and ucMSC were immune privileged and also possessed immunosuppressant properties. Furthermore, the cells cultured in MEMα suppressed the immune response to a greater extent than cells cultured in DMEM.
MSC from both sources showed varied differentiation potential towards the osteogenic and adipogenic lineages, but overall with low efficiency. All cells were positive for CD105, CD44, CD73 and HLA I and negative for CD45, CD31, CD14, CD80, HLA-DR and HLA II. MSC from uc were negative for CD34 and positive for CD90, whereas afMSC were intermediately positive for CD34 and CD90. The cells were cultured for 10 passages to investigate their proliferative capacity and their population doubling times were calculated. The average doubling time for afMSC was 49.3 ± 12,7 hours at passages 1 to 5, 42.3 ± 7.5 hours for ucMSC.
Conclusions
Based on this data we will in the forthcoming studies isolate cells from amitotic fluid using positive selection for various markers and culture the cells in MEMα. With these changes we hope to obtain a potent homogenous cell population that can be used in the treatment of congenital malformations.
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