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Totipotent, Pluripotent and Multipotent Stem Cells – What is the Difference?

Totipotent, Pluripotent and Multipotent Stem Cells – What is the Difference?

In this video let us talk about few terms that we frequently use when we talk about stem cells and they can be really confusing sometimes. I am talking about totipotent, pluripotent and multipotent stem cells. Like always first thing first. What are stem cells? Stem cells are undifferentiated, unspecialized cells which mean stem cells can differentiate into any type of cell present in our body and we have around 200+ cell types in our body and stem cell can give rise to any of them.

To understand these three terms we should know the categories of stem cells. Stem cells are classified under two categories, embryonic stem cells – found in embryo and adult stem cells – found in many organs. Embryonic stem cells can be either totipotent or pluripotent and adult stem cells are multipotent.

  1. Totipotent – “totus” means “whole”. The ability of zygote that it can differentiate into any type of cell (making a complete organism) is called totipotency. That is why a zygote is totipotent.
  2.  Pluripotent – “pluri” means “several”. The inner cell mass of the blastocyst has the ability to produce all the cell types of our body except for what trophoblast can form e.g., placenta, amniotic sac etc. So this means we have around 200+ cell types in our body and inner cell mass can differentiated into any of them, e.g., it can give rise to all the blood cells, cardiac muscles, neural cells. This ability of inner cell mass is called pluripotency. That is why inner cell mass is pluripotent.
  3. Multipotent – “multi” in this case means “few”. Pluripotent cells, as we already establish can differentiate in any of the cell type but multipotent cell would be more specified for one or more cell lines e.g., mesenchymal stem cell differentiates to form bone, cartilage, connective tissue, adipose tissue etc. So mesenchymal stem cell is multipotent.

Watch the video for better explanation.


Read short notes on this topic here

Read more about stem cells.

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Hematopoiesis – Overview [Blood Cell Formation]

Hematopoiesis – Overview

Hematopoiesis, also known as Hemopoiesis is formation and development of blood cells. Meaning of the term hematopoiesis is “Hemo = blood” and “poiesis = to form”. Hematopoiesis occurs in bone marrow. 

The starting point of Hemopoiesis is Hematopoietic Stem Cell (HSC) which is a pluripotent stem cell. What is pluripotent now?? The meaning of pluripotent is “pluri = several” and “potent = being able” which means the cell has ability to differentiate or give rise to several different types of cells.

The first differentiation of HSC results in two lineages – Myeloid stem cell and Lymphoid stem cell.

Myeloid stem cells differentiates into three progenitor cells – Colony Forming Unit – Erythrocyte (CFU-E), Colony Forming Unit – Megakaryocyte (CFU-Meg) and Colony Forming Unit – Granulocyte and Macrophage (CFU-GM). Once the progenitor cells are formed, the next stage is the formation of precursor cells (suffix “blast” will be applied in all precursor cells). So from CFU-E, proerythroblast will form. From CFU-Meg, megakaryoblast will form. From CFU-GM two precursor cell will form as the term suggest, monoblast and myeloblast and there will be two more precursor cells directly differentiating from myeloid stem cell and they are eosionophilic myelolast and basophilic myeloblast.

Lymphoid stem cells differentiates into two progenitor cells, i.e. prothymocyte and pre B-cell and they will develop into precursor cells T lymphoblast and B lymphoblast respectively. Here also there is one direct precursor cell formation without the progenitor cell stage and that is NK lymphoblast.

To read a blog post on this topic here which can be your quick short note.