Stem cells from bone marrow
Stem cells from adipose tissue
Stem cells from follicular fluid
Stem cells from bone marrow
In the adult body there are two main stem cell populations, both of them present in bone marrow: hematopoietic stem cells (HSCs) and mesenchymal stem cells or mesenchymal stromal cells (MSCs). HSCs include lymphoid and myeloid cell lines, from which all blood cells and immune system cells are derived, and are present in a number of organs. MSCs are defined as self-regenerating, multipotent stem cells with the ability to differentiate into multiple mesenchymal tissues such as bone, cartilage, muscle, adipose tissue and connective tissue of ligaments.
The main source of MSCs is the bone marrow, but they are also present in other human tissues such as adipose tissue, cord blood, chorionic villus of placenta, amniotic fluid, peripheral blood, lungs, etc. However, they constitute only a small proportion of the total cell content in each. In 1 ml of adult bone marrow there are 2000 MSCs, – 1 MSC for every 20.000 cells with a nucleus. When bone marrow cells are cultured, a population of cells becomes attached on the bottom of the growth flask, and they form a spindle shaped cell culture, similar to fibroblasts. This cell population comprises the mesenchymal stem cells.
Within the project ‘Development of tissue engineered bone substitutes’ (code: TP MIR 06/RR/12), we developed a bone substitute using stem cells from bone marrow. The cells were transferred to previously tested scaffold material and, during cultivation, they differentiated into osteoblasts. The phase of differentiation was monitored by evaluating the cell phenotype. We also identified cell viability in the final graft.
The usefulness of the product – the tissue engineered bone substitute, which was made under controlled laboratory conditions – was tested in a clinical study approved by the Commission of RS for Medical Ethics. Current results from the clinical study suggest that this form of the treatment of long bone defects is safe and potentially useful for the patient. Bone production in the grafted site was observed in all the patients treated by this method, more than half of whom can bear load on their leg.
Stem cells from adipose tissue
Until recently bone marrow has been the main source of adult stem cells. An alternative source of mesenchymal stem cells is adipose tissue. The surgical procedure of harvesting cells from adipose tissue is less invasive than from bone marrow. Also, more material can be collected and larger numbers of cells obtained. Stem cells from adipose tissue have the ability to differentiate into different cell types, including adipocytes, chondrocytes, osteoblasts and myocytes. Besides their differentiation potential they also possess strong angiogenesis stimulating potential and exhibit immune modulatory effects. Because of their characteristics they have a major potential for a variety of therapeutic applications.
Stem cells from follicular fluid
Stem cells are non-differentiated cells that have the ability to differentiate into a variety of cell types. This is a highly important property for future treatment of degenerative diseases in regenerative medicine. Embryonic stem cells have the greatest potential for differentiation and, under ´in vitro´ conditions, they can develop into practically any type of cell. Latest research indicates that stem cells, similar to embryonic stem cells, are also present in adult human tissues. They were found for example in bone marrow, testicles and in the surface epithelium of ovaries.
The goal of our research is to determine the presence of stem cells in follicular fluid obtained during egg cell aspiration in patients undergoing in vitro fertilization. The main aim is to determine whether cells from follicular fluid are capable of differentiation into different cell types and whether they are similar to embryonic stem cells. We are also interested in determining the effect of follicular fluid on the growth and differentiation of other types of stem cells.
In this research we are cooperating with doc. Dr. Irmo Virant-Klun from the Department of Gynaecology at the University Medical Centre, Ljubljana. The research is the subject of a patent application.