Spleen megakaryocytes

Figure 12 shows dynamics of the changes in the quantitative characteristics of spleen megakaryocytes. It is obvious that their dynamics is the same as in perivascular and peribronchial lymphoid infiltration study. Hence, perivascular and peribronchial lymphoid infiltration condition reflects systemic reaction of the lymphoid tissue of mice to the maximum concentration of the virus in the lungs and bacterial flora activation in case of MFPC Grinization application which results in more adequate and concordant immune response in animals from group II. 

Fig. 12. Comparative analysis of spleen megakaryocytes proliferation rates in animals from the group of control and animals administered MFPC Grinization .

IgG autoantibody-coated platelets induce Fey receptor-mediated phagocytosis by mononuclear macrophages, predominantly in the spleen and liver. Thrombocytopenia develops as a consequence of megakaryocyte inability to increase platelet production and maintain a normal number of circulating platelets. Currently used treatments are directed at different aspects of the antibody production, platelet sensitization, and the clearance and production cycle.30... 

Hematopoiesis is defined as the development and maturation of blood cells and their precursors. In utero, hematopoiesis may occur in the liver, spleen, and bone marrow. However, after birth, it occurs exclusively in the bone marrow. All blood cells are generated from a common hematopoietic precursor, or stem cell. These stem cells are self-renewing and pluripotent and thus are able to commit to any one of the different lines of maturation that give rise to platelet-producing megakaryocytes, lymphoid, erythroid, and myeloid cells. The myeloid cell line produces monocytes, basophils, neutrophils, and eosinophils, whereas the lymphoid stem cell differentiates to form circulating B and T lymphocytes. In contrast to the ordered development of normal cells, the development of leukemia seems to represent an arrest in differentiation at an early phase in the continuum of stem cell to mature cell.1... 

Physiologically, immunohaematopoietic stem cells give rise to progenitors that mature to recognizable megakaryocytes in the marrow. The latter release platelets into the circulation where they have a mean life-span of 10 days after which they are removed by the reticuloendothelial cells of the spleen, liver and bone marrow. There are three broad categories giving reduced counts. 

Platelets are produced by the fragmentation of megakaryocytes, the largest cell type in the bone marrow. Approximately one-third of the platelets are taken up by the spleen, while the other two-thirds freely circulate for 7-10 days until they are taken up by phagocytic cells. A normal platelet count is between 150000 and 450 000 mm The normal platelet count is quite variable and can be affected by an individual s nutritional state or, in females, by the menstrual cycle. 

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