Hematopoesis is an organize system that is responsible for blood cells production. The proliferation, differentiation and maturation control of this cells is achieved by interaction between cells and medular microenvironment. This microenvironment produce glicoproteins called cytokines, that control proliferation of hematopoietic cells. In neoplasic processes, several molecular alterations occur, it induce a new biological behaviour by cells, like become altered its adhesion. The interaction of leukemic cells with the extracellular matrix (ECM) of bone marrow can be considered one of the mechanisms used by these cells to reach the peripheric blood. Privately, precursor cells, ECM and endthelial cells control the maintennance or release of this hematopoietic cells to peripheric blood. In this way, changes in affinity or in molecular amount by stroma cells or by precursors of blood cells will afect cellular adhesion. Thefore several works have been realized to understand very much about the interaction between hematopoietic progenitors cells and the microenvironment constituted by medular stroma.
Leukemia; bone marrow