Оbject: bacterial keratitis. Purpuse: optimization of the transplantation methods of amniotic membrane (AMT), cryopreserved by a new technique, based on the study of the mechanisms of its influence on the peculiarities of inflammatory process and corneal regeneration in bacterial keratitis. Methods: visometry, biomicroscopy, fluorescein test, photoregistration of corneal changes, histomorphological and immunohistochemical studies of corneal tissue, statistical methods. Slit lamp, Jenamed-2 microscope, Canon digital camera. The model of bacterial keratitis which enables to obtain a standard clinical picture of bacterial keratitis of moderate severity in 100% of experimental animals, is developed, it can be used for studying of effectiveness of AMT as well as mechanisms of its influence on the course of keratitis (Patent number UA87119U Ukraine from 27.01.2014). The interconnection between inflammation and proliferative activity of epithelial cells and keratocytes on the developed model of bacterial keratitis, using immunohistochemical markers, which are manifested by the feedback between the proliferative activity of the cells of the anterior epithelium of the cornea (absence of Ki-67 expression) and the intensity of inflammatory corneal stromal infiltration (presence of expression of CD 68 and MMP-9) were investigated for the first time. Knowledge about the effect of transplantation of the amniotic membrane, cryopreserved by the new technique, on the processes of corneal regeneration, consisting in increasing of the number of stem cells in the limbal zone (presence of expression of vimentin) and their proliferation with involvement in the epithelization of the cornea (presence of Ki-67 expression), is extended. For the first time the anti-inflammatory properties of the amniotic membrane, cryopreserved by the new technique, are shown, which is confirmed by epithelization of the corneal surface at 73.3%, irrespectively to the technique of the graft on the 7-th day, resorption of inflammatory infiltration in the corneal tissue on the 14-th day in 90% of animals in the group with the biological covering and in 70% of animals in the group with layer transplantation of amniotic membrane. Аmniotic membrane transplantation, cryopreserved by the new technique, using biological covering technique is more effective compared with layer transplantation technique. It is expressed in absence of inflammatory infiltration, vascularization, and formation of intensive corneal clouding in all the animals on the 30-th day of the experiment, whereas in application the layer transplantation technique the above mentioned clinical features are observed in 40% of animals.The comparative study of the two techniques of amniotic membrane fixation, conducted on bacterial keratitis model, allows us to recommend application of the amniotic membrane transplantation, cryopreserved by the new technique, using biological covering technique in case of corneal ulcers up to 1/3 of the stroma in depth. On the basis of the conducted experimental studies we were given a license from the Coordination Center of Organ, Tissue and Cell Transplantation of Ukraine for studying effectiveness of AMT in patients with corneal pathology in the clinic (protocol № 1, January 24th 2017). The developed model of bacterial keratitis was used for experimenta lstudies according to the scientific topics of the Laboratory of Immunological Research. The result sof the study were introduced into the treatment protocols of the Department of Pathology of the Eye Cornea, SI «The Filatov institute of eye diseases and tissue therapy NAMS of Ukraine». Scope of application - medicine, ophthalmology.
