4.916667
#54-OR
BKV REPLICATION AND ACUTE REJECTION: DOES ONE TRIGGER THE OTHER?.
D. Dadhania MD ^1,2, C. Snopkowski BS ¹, T. Muthukumar MD ¹, R. Ding MD ¹, B. Li PhD ¹, V. Sharma PhD ^1,2 and M. Suthanthiran MD ^1,2. ¹ Nephrology & Transplantation Medicine, Cornell University, NY, NY, USA and ² Rogosin Institute, NY, NY, USA .

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BKV nephritis is a serious complication of renal transplantation. We have previously reported that steroid maintenance therapy is an independent risk factor for BKV replication. In the current study, we determined if BKV replication is more frequent in allograft recipients with a treated acute rejection (AR) episode whether clinical AR is more frequent in those with molecular BKV replication. We also investigated whether BKV replication is associated with a host cytotoxic T cell response. BKV replication was determined by measuring BKV VP1 mRNA and host cytotoxic T cell response was measured by mRNA levels of granzyme B, a prototypic cytotoxic attack molecule, and CD103, a cell surface protein expressed on CD8+ CTL. We studied 93 allograft recipients. AR was diagnosed in 9 of 93 recipients and the incidence of BKV replication was 22% in this cohort; the remaining 84 recipients free of clinical AR in the first 6-months of transplantation had a 35% incidence of BKV replication P=0.7. Nobody with BKV replication developed AR during the subsequent 6 months.
Our studies also identified that allograft recipients with BKV replication have an heightened cytotoxic response.

Levels of mRNA in Urinary Cells

	mRNA copies/ug total RNA
	BKV positive (N=30)	BKV negative (N=62)	P
GB	208,00099,880	53,97043,180	.03
CD103	27,630 11,100	5,729 2,040	.01

Our studies suggest: 1. BKV replication is not more frequent in recipients with treated AR 2.Clinical AR is not more frequent in recipients with BKV replication 3. BKV replication is associated with a host immune response. Long-term consequences of such response need to be studied.