Background: Crucial inflammatory mediators involved in development of alloimmune response leading to AR are cytokines. Our project was aimed to investigate the relation between the urine cytokine profile and the development of acute rejection (AR) episodes in patients after kidney transplantation.
Material/Methods: The project included 44 patients undergoing kidney transplantation. During the six-month period following the transplantation AR was diagnosed in 11 patients. Urine samples were collected 2, 4, 14 and 30 days posttransplantation and cytometrically tested for concentrations of IL-2, IL-4, IL-5, IL-10, IFN-γ and TNF-α.
Results: We found the elevated posttransplant concentrations of IFN-γ, IL-10 and TNF-α in the urine of patients with diagnosed AR vs. NONAR (P<.05). No significant differences in the urine concentrations of IL-2, IL-4, IL-5 between the two groups were observed (P>.05). Elevated concentrations of urine IFN-γ and TNF-α in AR patients, not accompanied by higher concentrations of IL-2, may suggest an ongoing undetected nonspecific Th1 immune response, capable of amplifying the alloimmune response in the early phase postsurgery, leading to AR. Higher concentrations of IL-10 found in the urine of AR patients, in turn, can partially result from peripheral regulatory mechanisms controlling the ongoing immune reaction, and partially from activation of monocytes/macrophages.
Conclusions: The results of our study suggest that higher concentrations of IFN-γ, TNF-α and IL-10 in the urine of patients shortly after the kidney transplantation can be considered as risk factors increasing the probability of AR episodes.

Keywords: Kidney Transplantation, acute rejection, Th1/Th2 cytokines, urine, cytometry