Kroemer et al at Georgetown-Medstar Transplant Institute in Washington, DC, recently reported the first ever intestine transplant recipient to show operational tolerance or a stable rejection-free status without immunosuppression. Phenotypic analysis of peripheral blood lymphocytes revealed an increase in circulating T-regulatory cells. This patient also demonstrated immunological quiescence toward donor alloantigens. Immunological reactivity toward other antigens was preserved. These functional tests were performed at Plexision. Specifically, donor-reactive T-cytotoxic memory cells and donor-specific antigen presenting B-cells and monocytes were greatly reduced. T-cell reactivity to cytomegalovirus and mitogens was unaffected.

Reference: Kroemer A, Khan K, Kaufman SS, Kang J, Weiner J, Duttargi A, Belyayev L, Ashokkumar C, Sindhi R, Timofeeva OA, Zasloff M, Matsumoto CS, Fishbein TM. Operational tolerance in intestinal transplantation. Am J Transplant. 2020 Jul 28. doi: 10.1111/ajt.16224. Online ahead of print. PMID: 32721092