Regulatory T cell expression of CLA or [alpha]4[beta]7 and skin or gut acute GVHD outcomes

• Published in: Bone marrow transplantation (Basingstoke) Vol. 46; no. 3; p. 436
• Main Authors: Engelhardt, B G, Jagasia, M, Savani, B N, Bratcher, N L, Greer, J P, Jiang, A, Kassim, A A, Lu, P, Schuening, F, Yoder, S M, Rock, M T, Crowe, J E
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 01.03.2011
• Subjects: Bone marrow; Stem cell transplantation
• ISSN: 0268-3369; 1476-5365
• DOI: 10.1038/bmt.2010.127

Regulatory T cells (Tregs) are a suppressive subset of CD4(+) T lymphocytes implicated in the prevention of acute GVHD (aGVHD) after allo-SCT (ASCT). To determine whether increased frequency of Tregs with a skin-homing (cutaneous lymphocyte Ag, CLA(+)) or a gut-homing (α(4)[beta](7)(+)) phenotype is associated with reduced risk of skin or gut aGVHD, respectively, we quantified circulating CLA(+) or α(4)[beta](7)(+) on Tregs at the time of neutrophil engraftment in 43 patients undergoing ASCT. Increased CLA(+) Tregs at engraftment was associated with the prevention of skin aGVHD (2.6 vs 1.7%; P=0.038 (no skin aGVHD vs skin aGVHD)), and increased frequencies of CLA(+) and α(4)[beta](7)(+) Tregs were negatively correlated with severity of skin aGVHD (odds ratio (OR), 0.67; 95% confidence interval (CI), 0.46-0.98; P=0.041) or gut aGVHD (OR, 0.93; 95% CI, 0.88-0.99; P=0.031), respectively. This initial report suggests that Treg tissue-homing subsets help to regulate organ-specific risk and severity of aGVHD after human ASCT. These results need to be validated in a larger, multicenter cohort.