# Measuring the Impact of Allosensitization on Xenotransplantation > **NIH NIH R21** · DUKE UNIVERSITY · 2020 · $241,500 ## Abstract Antibody-mediated rejection (AMR) is a barrier to successful long-term xenograft survival. We compared AMR in kidney xenotransplantation to sensitized kidney allotransplantation in a NHP model. With conventional CNI- based immunosuppressive maintenance, both groups showed limited graft survival with strong AMR features such as interstitial hemorrhage, thrombotic microangiopathy, peritubular capillaritis, and glomerulitis without T cell mediated rejection. The strong similarity between sensitized allo- and unsensitized xeno-rejection suggests a possible common mechanism of rejection in xeno- and sensitized allotransplantation. Currently pig to primate graft survival has markedly improved with interruption of the CD28/B7 and CD40/CD154 costimulation pathways. In theory, the same regimen should control the immune response against xenografts in allosensitized animals. Therefore, further investigation is warranted to evaluate the current successful costimulation blockade-based regimen that has shown great efficacy in xenotransplantation to determine if this strategy may apply as well to sensitized recipients. ## Key facts - **NIH application ID:** 9956029 - **Project number:** 1R21AI151398-01 - **Recipient organization:** DUKE UNIVERSITY - **Principal Investigator:** Stuart Johnston Knechtle - **Activity code:** R21 (R01, R21, SBIR, etc.) - **Funding institute:** NIH - **Fiscal year:** 2020 - **Award amount:** $241,500 - **Award type:** 1 - **Project period:** 2020-03-12 → 2022-02-28 ## Primary source NIH RePORTER: https://reporter.nih.gov/project-details/9956029 ## Citation > US National Institutes of Health, RePORTER application 9956029, Measuring the Impact of Allosensitization on Xenotransplantation (1R21AI151398-01). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9956029. Licensed CC0. --- *[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*