The aim. The research deals with analysis of the degree of regenerative processes activity in patients with trophic venous ulcers of the lower extremities that do not heal for a long time on the background of cell transplantation of cord blood stem cells and without. The study involved 32 patients with long-term non-healing trophic venous ulcers of venous etiology. Results and discussion. The study results showed that the healing process of the main group patients began in the first days after transplantation to reduce pericellular edema and inflammatory hyperemia of the soft tissues around the ulcer. When examining the histological features of the central skin ulcers of patients in the control group on the fifth day after treatment, we found out that the bottom surface of the ulcers was covered with homogeneous masses of the type of fibrinoid necrosis. Ulcers had a variable depth, in some places reached the fiber, with sweat and sebaceous glands, hair follicles in the course of defects were completely destroyed, in these places there were hemorrhages and young granulation tissue. In patients of the main group, the surface of the bottom of the ulcer was covered with homogeneous masses of fibrinoid necrosis, but the masses of fibrinoid necrosis were visually expressed three times less than in the control group, but the most important was that they always alternated with "veins" consisting of cells type of lymphoid. Immunohistochemical analysis for Willebrand factor in patients of the main group revealed unevenly scattered small compact groups of positively stained cells, which should be evaluated as foci of neoplasms of blood vessels more evenly distributed among the blood vessels of granulation tissue, in contrast to the control group. On the 14th day of the clinical study at the bottom of the ulcer in the main group there were morphological signs of better maturation of granulation tissue, as seen by more uniform and intensive processes of collagen fiber formation (increase in specific volume of collagen fibers) and blood vessels (decrease in specific volume of blood vessels) and the maturation of lymphoid (polypotent) cells into fibroblasts with more complete production of vimentin in them and endothelial cells with more complete production of Willebrand factor in them. It should be noted that there was a more complete resorption of fibrinoid necrosis masses in the main observation group compared to the control group of patients, which should also contribute to faster and more complete healing of the ulcer
