LIM Zinc Finger Domain Containing 1 Risk Genotype of Recipient Is Associated with Renal Tubular Inflammation in Kidney Transplantation.

Background: Homozygosity for rs893403-GG genotype is linked to an increased risk of allograft rejection after kidney transplantation. Ischemia-reperfusion of the kidney allograft leads to long term infiltration of activated and effector-memory T lymphocytes and resulting in rejection and long-term fibrosis. However, the genotype, expression under ischemic conditions and the long-term histopathological relationships remain ill-defined.

Methods: We examined the impact of the recipient's -rs893403 genotype with transplant kidney histopathology. The association of the -rs893403 genotype and and mRNA expression in ischemic donor kidneys were also examined. Recipients who underwent transplant kidney biopsy were genotyped for the -rs893403 variant and associated deletion. Histopathological findings were compared between recipients with risk and non-risk genotypes. Real-time PCR and immunofluorescence staining for and expression were performed in non-utilized donor kidneys.

Results: Demographic, clinical, and treatment characteristics and the histopathological diagnosis were similar between recipients with rs893403 GG and AA/AG genotype. The Banff tubulitis score was higher in GG recipients (n = 24) compared to AA/AG (n = 86) recipients (1.42 ± 0.65 vs. 1.12 ± 0.66, = 0.03). Ischemic kidneys with GG showed higher and mRNA expression than kidneys with AG. Kidneys with rs893403-GG had higher tubular LIMS1 and GCC2 immunohistochemical staining compared to kidneys with rs893403-AG.

Conclusions: Our data supports the role of the locus in kidney transplant rejection, particularly in lymphocyte infiltration into the internal aspect of the tubular basement membranes. Increased and expression in ischemic donor kidneys with the GG genotype require further studies.