Tissue transplant bioengineering is based on the idea of employing scaffolds, both natural and artificial, constituting a three-dimensional scaffolding on which cells settle, seed, and differentiate into a new organ. Due to a relatively simple structure of these organs, oxygen and nutrients demand first takes place by diffusion, which allows neoangiogenesis to develop gradually. In recent years many groups of researchers have claimed to have used autologous cells for reconstruction of relatively simple organs, such as vessels, the urinary bladder, the upper airways, the oesophagus, and the urethra, which were transplanted to patients with acceptable organ function with a short and medium postoperative time period. According to a growing number of scientists, there is a way to use such organs for transplantation by means of bioengineering and regeneration. One of the potential sources is the kidneys which cannot be transplanted immediately after excision due to anatomical anomalies, advanced glomerulosclerosis, tubular atrophy, interstitial fibrosis, renal vessel disease, necrosis of the renal cortex, as well as factors exceeding the allowed time of cold renal ischaemia, lengthy duration of warm ischaemia, and renal function insufficiency. Taking into account all of the abovementioned information, there exists a need for an inexhaustible source of transplant organs. The mortality rate in the group of chronically dialysed patients awaiting the transplant is much higher than in the patient group after transplant surgery, even if the so-called suboptimal organs were employed. However, all of this is still insufficient in comparison to the number of recipients awaiting the transplant. The donor pools have been expanded to include living donors, related and unrelated ones, pair exchange, and the expansion of marginal kidney donor criteria. Excellent results of transplants have been reflected in the demand for the transplant organs, which is significantly higher than the available supplies. What is more, all these factors have also prolonged the lifespan of organs and their recipients. Immunological discoveries, the introduction of new medications, and the improvement of the immunosuppressive protocols have led to a further development of transplantology. The surgery made it possible to transplant kidneys as a way to manage chronic kidney failure and shifted organ transplantation from the area of experimental treatment to a clinical method. The first successful kidney transplants date back to 1954 when in Boston (USA) Joseph Murray and John Merrill together with their team managed to successfully transplant a kidney between monozygotic twins without immunosuppressant treatment. Thus, the optimum treatment would be to replace the disabled organ with a healthy kidney. However, the role of kidneys is not limited to mechanical filtration and blood cleansing, but also involves hormone secretion, red blood cells production, and bone metabolism through calcium-phosphorus balance. What is necessary to raise the patients' quality of life is an improvement of the filtration structure of membranes and the refinement of filtration parameters. Moreover, haemodialysis makes the lives of the patients suboptimal and generates high costs of treatment. Filtration during haemodialysis is not entirely physiological due to membrane filtration restrictions resulting from thickness, shapes, and the size of the pores, as well as from occlusions with protein deposits and blood clotting. The dialysed patients still present high morbidity rates in terms of comorbidities, as well as high mortality rates. Pharmacological nephroprotection has turned out to be ineffective in the long run therefore, it is necessary to employ renal replacement therapy (RRT), usually haemodialysis (HD). The main causes of kidney failure patients include glomerulonephritis, diabetic kidney disease, hypertensive nephropathy, polycystic kidney disease, Alport syndrome, and other factors, which gradually decrease the glomerular filtration rate. The number of patients suffering from end stage renal disease (ESRD) is rising every year.
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