Introduction to hematology

 

Hematology is the study of blood flowing through blood vessels carrying oxygen, nutrients, and waste, including the function of formation and disease of blood components such as red blood cells (erythrocytes or erythrocytes), white blood cells (leukocytes ), platelets, and lymphoid organs and tissues.

We can divide the blood taking into account its density, in 2 fractions:

- Formed fraction (Hematocrit; 45% of total blood volume): This fraction provides the characteristic viscosity of blood and comprises 41% erythrocytes, 4% leukocytes and finally platelets with a value of 0.01%.

- Liquid fraction (55% of total blood volume): composed mainly of water and to a lesser extent proteins, carbohydrates, lipids, electrolytes, waste...

In turn, this fraction can be classified into two types depending on whether or not an anticoagulant has been used in the blood collection: plasma is obtained by centrifugation of anticoagulated blood and serum by centrifugation of non-anticoagulated blood (it is an irreversible process).

Thus, hematopoiesis is responsible for the formation of new blood cells (named above) every day, in it they will renew, proliferate, differentiate and finally each one of them will specialize. It is produced in the fetal liver, spleen, and mainly in the bone marrow (B.M.), which is found in an adult in the ribs, vertebrae, pelvis, skull, clavicles, sternum, and proximal long bones.

Hematopoietic stem cells undergo mitosis differentiation and maturation to become the final cell type, the cells will travel outside of bone to enter the general circulation and lymphoid tissues, thus hematopoietic stem cells are totipotent, i.e. , is capable of dividing and differentiating into any type of blood cell.