[Emperipolesis and interrelations of megakaryocytes and neutrophilic granulocytes in the bone marrow of healthy dogs].

Emperipolesis is an ability of one cell to penetrate into cytoplasm of another cell and to stay there for some time, or to pass through it. Unlike a common phagocytosis, not a cell interacting is damaged. Penetration of neutrophilic granulocytes into cytoplasm of megakaryocytes is also considered as emperipolesis, that is revealed in the bone marrow of healthy persons. Its occurrence becomes greater at various pathological states of tumorous and non-tumorous etiology. Histological investigation of the bone marrow of the rib, breast bone, vertebral body and iliac bone crest, performed in 10 healthy dogs makes it possible to state, that there are possible specific interrelations between megakaryocytes and neutrophilic granulocytes, that terminate in death of the former. Therefore, the phenomenon observed cannot be identified with emperipolesis. In this case we, evidently, deal with a morphological demonstration of cell cytotoxicity, when neutrophils, being killers, act as effector-cells, and megakaryocytes - as target-cells. Cell cytotoxicity is a natural phenomenon, that under certain physiological conditions is evidently connected with thrombocytopoiesis.