Stem cells are unspecialized cells found in multi-cellular organisms with
an ability to proliferate into any one of the body’s more than 200 cell types. In
a simpler language, these cells can be transformed into other cell type, found in
the body on being given the right stimuli. Thus, they can be recreated to form liver,
skin, red blood cells etc. The ability of the stem cells to transform varies, as
some are more adaptable to transformation than others.
These are characteristically of the same type. Scientists have developed a special
technology through which they can mould these cells to become the precisely the
same cell that is required.
These cells can grow into anyone of the body’s more
than 200 cell types. These cells retain the ability to divide throughout their life.
The advancement in research has helped create interest in exploring the possibilities
of fully functional differentiated cells such as cardiomyocytes, neurons and bone
and cartilage. Primarily, these stems cells are divided into
- Embryonic stem cells and umbilical cord stem cells- Both are
different sources of deriving human embryonic stem cells. These are pluripotent
cells which mean that they can divide into any of the three germ layers such as
endoderm (inner stomach lining, lung and gastrointestinal tract), mesoderm (urogenitals,
muscle, bone and blood), ectoderm (epidermal tissue and nervous system). These cells
are more adaptable and can give rise to any fetal or fully grown cell type.
- Developed stem cells- these are multipotent cells which can
give rise to only limited type of cells. These are again differentiated into
- Neuronal stem cells
- Haematopoietic stem cells
- Skin stem cells
Each of these can give rise to only specific cell types such as neuronal stem cells. These neuronal stem cells
can give rise to only nerve cells and not blood cells or liver cells. Thus, their function is limited
The scientific human embryonic cells (hES) have triggered many debates in the recent
times. The impacts of these debates have been so deep that it has affected the progress
of the researches and clinical trials that this therapy is undergoing. Despite all
this, scientists are committed and further research is on. The scientists are attempting
different ways of isolating these cells in improved cultural conditions, such that
its does not provoke ethical and political conflicts.
Collection issues While extracting the cell it is important to ensure that
the cells are free from microbiological contamination, can be identified easily
and they are away from circumstances that can change their genotype (internal coding
or blue print) and phenotype (physical appearance of the organism).