The first experience of cord blood stem cells application in kidney transplantation: A descriptive study

Kidney transplantation is recognized as the optimal method of end-stage kidney disease treatment, but chronic renal allograft rejection remains an unresolved issue and leads to transplanted organ function loss. Recent studies show positive effects of stem cell injections in a variety of diseases, including kidney transplantation. The present study aimed to analyze the first experience of umbilical cord blood stem cells application in living-related kidney transplantation in Shalimov's National Institute of Surgery and Transplantation, give a preliminary assessment of their effectiveness and safety, evaluate the clinical course and especially the dynamics of laboratory parameters in the recipient's postoperative period. Methods. The study group included 6 male, adult recipients of kidney transplants, who performed the first kidney allotransplantation from a living family donor in the Shalimov's National Institute of Surgery and Transplantology in 2020 – 2021. Before surgery, all patients received intravenous administration of a fraction of nuclear cells from human umbilical cord blood at a dose of 2-3 x 106/kg body weight in combination with standard three-component immunosuppressive therapy. Immune system studies were performed before kidney transplantation, on the first and third days of the postoperative period, at the end of the first and second week, as well as on the first, third, sixth, and twelfth months, following kidney transplantation. Renal graft function was assessed by serum creatinine and glomerular filtration rate. Monitoring of clinical and laboratory parameters of blood and urine, the concentration of calcineurin inhibitors (C0) was carried out regularly three times a week for the first month, twice a month for 2-3 months, and once a month until the end of the year. Puncture biopsy of the transplanted kidney was performed three months after surgery to diagnose the pathology of the graft, namely the manifestations of acute and chronic rejection, the nature and degree of which were determined according to the Banff classification. The state of the immune system of the recipients was characterized by indicators of cellular and humoral immunity. Statistical processing of research results was performed using the statistical package StatSoft (2010) STATISTICA 9.1 for Windows StatSoft Inc, Tusla. Results. All patients received cord blood stem cells without complications. On the first day after surgery, an average diuresis was 9415 ± 928.1 ml. Normalization of graft function was observed on the second or third day (GFR more than 90 ml/ min/1.73 m2). There were no rejections of grafts and signs of opportunistic infections in the patients during 1 year follow-up period. Morphological studies did not reveal signs of significant pathological changes in transplanted kidneys in patients who received stem cells as induction therapy. The study of the state of the immune system of recipients in the dynamics, given the insufficient number of patients, requires further research. Conclusions. The administration of cord blood stem cells to recipients prior to kidney transplantation is safe and promotes rapid recovery of renal allograft function. There were no signs of morphological proven chronic graft rejection, which allows us to predict its long-term functioning in the future. To assess the response of the recipient's immune system to the application of cord blood stem cells requires the accumulation of additional data.