Background: After organ transplantation DNA from passenger cells and
ischemia and rejection damaged cells is disseminated in the recipient. The
question is whether this DNA may be incorporated into recipient cell genome in the process of the so called "illegitimate DNA incorporation" - a frequent phenomenon in nature. Aim: To search for the donor DNA in recipient tissues and cells after allogeneic transplantation and immunosuppression.
Material/Methods: Recipient's blood samples were collected before and after kidney transplantation on 1,14,28,90,180,360 and 720 days and genomic DNA was isolated. Short tandem repeats analysis (STR) was applied. The investigated loci were: phospholipase A2-HUMPLA2A1(AAT)n, cytochrome P450 HUMCYARO(AAAT)n and D1S80.
Results: Donor cytochrome P450 or HUMPLA2 or D1S80 genes were detected
in recipient blood cells up to 2 years after kidney transplantation. Positive results were observed 24hr after grafting in 3 out of 3pts and in 4 out of 4 pts after 14
days, in 28 out of 28 after 28, in 2 out of 2 after 90, in 3 after 180, in 1 after 1 and in 2 out of 2 after 2 years.
Conclusions: Donor DNA can be detected in recipient blood cells 2 years after kidney transplantation. The question as to whether the detected donor DNA was contained in the surviving donor cells or in a form of apoptotic or necrotic bodies in recipient phagocytes or whether was incorporated into recipient cell genome remains to be answered. Recent study documents show the presence of the donor DNA in the nuclei of recipient's APCs.

Keywords: Kidney Transplantation