Pentraxin 3 expression in ABO-incompatible kidney allograft with antibody- mediated rejection

Abstract

［Background］Pentraxin 3 (PTX3) is one of the acute phase reactant protein produced in inflammatory local lesions. We reported that the up-regulated expression in allograft interstitium and the elevated concentration in plasma of PTX3 at acute rejection. In Banff classification, C4d deposition on peritubular capillary (C4d on PTC) is one of the histological diagnostic criteria for antibody-mediated rejection (ABMR), but its expression observed nonspecifically in the ABO blood group incompatibility (ABO-I) transplanted kidney allograft.［Purpose］Clarify whether the PTX3 expression in the ABO-I kidney allograft can become the histological marker of ABMR. ［Method］We examined the PTX3 expression in renal biopsy specimen from patients who underwent ABO-I kidney transplantation with ABMR (n＝4) and without ABMR (n＝16) by immunohistochemistry.［Result］PTX3 was positive in 3 cases in ABMR group, and negative in all cases of non-ABMR group. C4d was positive in all cases of ABMR group, and 12 cases of non-ABMR group. The sensitivity and specificity for the diagnosis of ABMR were 75% and 100% in the PTX3, and C4d were 100% and 25%, respectively.［Conclusion］The possibility that the PTX3 positive conversion could become the histological indicator for the differentiation of ABMR in the ABO-I kidney allograft, was suggested.