The expression profile of miRNA biogenesis components of renal transplant patients

In transplantation area, biomarker studies are conducted to determine the graft outcome before clinical symptoms. In recent years, miRNAs are considered as biomarkers for diagnosis and prognosis of many diseases. In this respect, we sought to determine the impact of immunosuppressant drugs on the levels of miRNA biogenesis components before and 3 months after transplantation. We investigated the expression levels of Dicer, Drosha, DGCR8, Argonaute2 and Exportin5 using lysates of peripheral blood mononuclear cells of kidney transplantation patients before and 3 months after transplantation. Expression levels of Dicer, Drosha, DGCR8 and Argonaute2 decreased and that of Exportin5 did not change in patients who did not reject the graft. However, we have seen changes in expressions of above proteins except Dicer in patient who showed chronic rejection and we observed increase in expression of Exportin5 in patient who showed acute rejection. mRNA expression levels of all genes mentioned above showed statistically significant decrease 3 months after transplantation and this decrease was even greater in patient who showed chronic rejection. In addition to these, Dicer expression did not change while Argonaute2 expression increased in patient who received Everolimus. In conclusion, our study indicates that use of immunosuppressive drugs may have an impact on synthesis of miRNAs and can be used as potential biomarker to follow the nature of transplanted organ.