Тромбоцити: біологічні властивості та клінічний потенціал

Abstract

В статті представлений огляд робіт, де розглянуто морфологію, вміст та біологічні властивості тромбоцитів. Автором систематизовано дані щодо застосування тромбоцитів в різних біотехнологічних варіантах в експериментальних та клінічних дослідженнях, а також викладені результати власного досвіду роботи зі збагаченою тромбоцитами плазмою при моделюванні патологічних процесів у тварин.

The key feature of platelets is the absence of the nucleus what makes them immunologically safe for use in the allogenic variant. However, platelets contain a large number of biologically actve compounds that are involved in a wide range of hemostasis processes, actvaton of neoangiogenesis, stmulaton of regeneratve propertes of tssues, support of homeostasis, and others. Afer aggregaton, the platelets begin to realize the contents of the granules, and this process most actvely lasts for the frst hour, and the synthesis of cytokines contnues for at least 7 days. Platelet-rich plasma (PRP) began to be manufactured for clinical purposes in the 1970s. It is a platelet concentrate in a small amount of plasma, with 5 tmes increase of the platelet concentraton, but the clinical signifcance has a PRP with a platelet content of not less than 1x106 / ml. Actually, not only platelets, but also a small number of red blood cells and leukocytes, including progenitor cells of varying degrees of maturity, are present in the PRP. Some pathological conditons of an organism influence quanttatve and qualitatve characteristcs of platelets and limit the possibility of their use in the autologous version. Our studies have revealed the ultra-microscopic features of platelets in rats with induced toxic hepatts. Thus, there was a change in the rato of actvated and unactvated platelets to the increase of the later, signifcant fluctuatons of the plate aggregaton index within the experimental group, a signifcant decrease in the density of alpha and delta granules. The release of cytokines, chemokines and growth factors from platelets stmulates the actvaton and proliferaton of regeneratve cells: fbroblasts, neutrophils, monocytes, smooth myocytes and mesenchymal stem cells. Of interest is the fact that the concentraton of growth factors in PRP almost 8 tmes exceeds their content in the whole blood. In a series of studies we performed on rats demonstrated a signifcant improvement of morpho-functonal state of the liver in animals with CCl4-induced chronic hepatts afer PRP administraton. It was noted that the introducton of PRP leads to normalizaton of blood biochemical characteristcs, revealed the amount of connectve tssue and speed up the process of regeneraton of liver tssue. We also demonstrated the applicaton of PRP under the experimental liver cirrhosis in rats induces actve regeneraton, normalizaton of liver size, rebuilt lobular organizaton, the newly formed blood vessels, increase content of PAS-positve substances. The researchers found the need for direct contact of the platelets and hepatocytes to implement proliferatve effect because it triggers signaling to actvate the growth factors. To correct degeneratve changes in the intervertebral discs of the spine we carried out experimental therapy by PRP that reduce the number of lesions fbronecrosis, the degree of desorganisaton of collagen fbers, increase the height of the fbrous ring and the vertebral epiphysis. Thus, these data indicate that currently experimental studies show high clinical potental of platelets, which is not substancially involved in the clinic. The uniqueness of these cells is due, above all, the ability to use them both autologous and in heterogeneous form, the use of products with platelets and cell mixtures in various biotechnological optons also availability and relatvely simple preparaton for clinical use.

В статье представлен обзор работ, где рассмотрена морфология, содержимое и биологические свойства тромбоцитов. Автором систематизированы данные о применении тромбоцитов в разных биотехнологических вариантах в экспериментальных и клинических исследованиях, а также изложены результаты собственного опыта работы с обогащенной тромбоцитами плазмой при моделировании патологических процессов у животных.