Today let’s take the opportunity to discuss the very elusive and less understood topic amongst many – stem cells. An overview of their origin, behaviour and most importantly functions.
Just imagine the stem cell as the mother of all cells – the one who nurtures and teaches the other cells, transforming them into adult cells with specific roles and responsibilities within the human body. Like in all hierarchy, there is one that also exists in this stem cell world. Some stem cells have greater capacity to differentiate and direct tissue systems, where as other stem cells may only have limited power and life span. It makes sense that stem cells would be more effective when obtained from an actively growing life source, whereby their degree of differentiation and maturity would be unrivalled.
They serve as an internal repair system, dividing essentially without limit to replenish other cells as long as the person or animal is still alive. When a stem cell divides, each new cell has the potential either to remain a stem cell or become another type of cell with a more specialized function, such as a muscle cell, a red blood cell, or a brain cell. Stem cells are capable of replication, proliferation, differentiation and long term cell renewal.
Broadly stem cells are categorised as Embryonic and Non Embryonic (adult). Embryonic stem cells are derived from the embryo, as the name implies. These cells are very versatile and can differentiate into any cell type. Adult stem cells on the other hand, are not from the embryo, but instead from specific tissue systems like blood, muscle, skin etc. They can only differentiate into their own lineage and kind. The word “potency” describes the degree of differentiation capable of a stem cell.
The extensive research on stem cells and its capacity to replenish itself has brought about a profound eye opening in the medical world. Most research is on adult stem cells, as studying human embryonic cells is deemed unethical – and rightfully so too.
Just to add on, a popular subtype of adult stem cells are Mesenchymal Stem Cells. Mesenchymal stem cells (MSCs) are adult stem cells traditionally found in the bone marrow. They can also be isolated from other tissues including cord blood, peripheral blood, fallopian tube, and fetal liver and lung. Multipotent stem cells, MSCs differentiate to form adipocytes, cartilage, bone, tendons, muscle, and skin. Mesenchymal stem cells are a distinct entity to the mesenchyme, embryonic connective tissue which is derived from the mesoderm and differentiates to form hematopoietic stem cells.
So in conclusion, we have this great repair system whose consumables consist of our very own blood, fat and skin. Really makes life a whole lot easier when one needs a new kidney.
In actual fact however, stem cell research has pioneered numerous success stories. Stem cells are being used to treat a variety of disorders like Parkinsons, myocardial ischaemia, congenital disorders and many more. In years to come, we should be able to regenerate faulty organs within the body and restore balance and homeostasis.