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Influence of new cryopreservation protocol on immunogenicity and rejection of arterial allografts in rats
Hrubý, Jan ; Matia, Ivan (advisor) ; Oliverius, Martin (referee) ; Štádler, Petr (referee)
The aim of the presented experimental work was to study an acute cell and antibody- mediated immune response in recipients of abdominal aortic grafts treated by a new standardized clinical cryopreservation/slow thawing protocol used in the "Vascular graft transplant program in the Czech Republic" in a rat model. Another aim of our study was to compare the influence of two basic types of conservation protocols used in this program (cryopreservation/slow thawing protocol and cold-stored protocol) on the acute immune response after transplantation of such treated abdominal aortic grafts in rats. Cryopreserved abdominal aortic grafts were transplanted syngeneously between Lewis rats (CRYO-ISO group, cryopreservation period 172.6 days) and allogeneically between Brown-Norway and Lewis rats (CRYO-ALO group, cryopreservation period 179.3 days). The grafts were explanted on day 30 after transplantation and subsequently examined by histological and immunohistochemical methods, focusing on typical signs of acute rejection in the three basic layers of the aortic wall. We monitored the presence of endothelial cells, signs of intimal hyperplasia, tunica media thickness, the presence of necrosis and deposition of imunoglobulin class G in this layer, the number of CD4+, CD8+ and LEW MHC II+ immunocompetent cells...
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Intestinal transplantation on an experimental model.
Oliverius, Martin ; Adamec, Miloš (advisor) ; Gürlich, Robert (referee) ; Kala, Zdeněk (referee)
Intestinal transplantation represents a life-saving procedure for patients with an intestinal failure. An experiment on pigs was carried out during the preparation part of a clinical project in the Czech Republic. The main aim of the experiment was to successfully master the transplant surgery technique (i.e. small bowel harvesting, its preservation, followed by the transplantation). Another goal was to decide on the optimal immunosuppressive regime. Immunosuppression was based on tacrolimus monotherapy or its combination with sirolimus. A graft biopsy still remains the most reliable method for the diagnosis of an acute cellular rejection. In an attempt to find a suitable noninvasive humoral marker of the acute cellular rejection, we examined the correlation between plasma citrulin level and the acute rejection. The plasmatic level of proinflamatory and antiinflamatory cytokines was investigated as another potential marker of the rejection. We succeeded in standardizing the technique of intestinal transplantation. Connecting the graft to aorta and inferior vena cava is simpler and safer than connecting it to the portomesenteric vessel bed due to fewer subsequent complications. Both immunosuppressive regimes seem to be equally effective in preventing the acute cellular rejection. Histopathological...
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Allogenous venous graft in reconstructive vascular surgery - the use of immunosuppression in experiment.
Varga, Martin ; Oliverius, Martin (advisor) ; Vaněk, Ivan (referee) ; Staffa, Robert (referee)
(ENGLISH) Background: The investigation of the immunosuppression usage in cardiovascular surgery and interventional cardiology is, at present, concentrated on three main topics: 1) influence on intimal hyperplasia of coronary and peripheral vascular reconstructions 2) influence on rejection of allogeneic vascular grafts and 3) influence on intimal hyperplasia of coronary arteries after endovascular interventions. Modern immunosuppressive drug FK506 (Tacrolimus) could have a positive effect for these indications. In experimental study, FK506 inhibited rejection of arterial allografts and also inhibited intimal hyperplasia in percutaneous coronary interventions. Aims: The purpose of this study was to evaluate the effect of systemic tacrolimus treatment on the process of arterialisation of allogeneic and syngeneic venous grafts in a rat vein-to-artery implantation model. Material and Methods: Lewis (LEW) rats were used as recipients of syngeneic (Lewis) or allogeneic (Brown-Norway; BN) iliolumbar veins which were implanted into abdominal aorta. Recipients were divided into six groups. In groups A, E and F were animals after syngeneic (LEW to LEW) and in groups B, C and D were animals after allogeneic (BN to LEW) transplantations. Animals in the groups C and F had daily intramuscular injections of...
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Allogenous venous graft in reconstructive vascular surgery - the use of immunosuppression in experiment.
Varga, Martin ; Oliverius, Martin (advisor) ; Vaněk, Ivan (referee) ; Staffa, Robert (referee)
(ENGLISH) Background: The investigation of the immunosuppression usage in cardiovascular surgery and interventional cardiology is, at present, concentrated on three main topics: 1) influence on intimal hyperplasia of coronary and peripheral vascular reconstructions 2) influence on rejection of allogeneic vascular grafts and 3) influence on intimal hyperplasia of coronary arteries after endovascular interventions. Modern immunosuppressive drug FK506 (Tacrolimus) could have a positive effect for these indications. In experimental study, FK506 inhibited rejection of arterial allografts and also inhibited intimal hyperplasia in percutaneous coronary interventions. Aims: The purpose of this study was to evaluate the effect of systemic tacrolimus treatment on the process of arterialisation of allogeneic and syngeneic venous grafts in a rat vein-to-artery implantation model. Material and Methods: Lewis (LEW) rats were used as recipients of syngeneic (Lewis) or allogeneic (Brown-Norway; BN) iliolumbar veins which were implanted into abdominal aorta. Recipients were divided into six groups. In groups A, E and F were animals after syngeneic (LEW to LEW) and in groups B, C and D were animals after allogeneic (BN to LEW) transplantations. Animals in the groups C and F had daily intramuscular injections of...
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Intestinal transplantation on an experimental model.
Oliverius, Martin ; Adamec, Miloš (advisor) ; Gürlich, Robert (referee) ; Kala, Zdeněk (referee)
Intestinal transplantation represents a life-saving procedure for patients with an intestinal failure. An experiment on pigs was carried out during the preparation part of a clinical project in the Czech Republic. The main aim of the experiment was to successfully master the transplant surgery technique (i.e. small bowel harvesting, its preservation, followed by the transplantation). Another goal was to decide on the optimal immunosuppressive regime. Immunosuppression was based on tacrolimus monotherapy or its combination with sirolimus. A graft biopsy still remains the most reliable method for the diagnosis of an acute cellular rejection. In an attempt to find a suitable noninvasive humoral marker of the acute cellular rejection, we examined the correlation between plasma citrulin level and the acute rejection. The plasmatic level of proinflamatory and antiinflamatory cytokines was investigated as another potential marker of the rejection. We succeeded in standardizing the technique of intestinal transplantation. Connecting the graft to aorta and inferior vena cava is simpler and safer than connecting it to the portomesenteric vessel bed due to fewer subsequent complications. Both immunosuppressive regimes seem to be equally effective in preventing the acute cellular rejection. Histopathological...
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