Lamin A/C deficiency in CD4+ T-cells enhances regulatory T-cells and prevents inflammatory bowel disease

The mechanisms by which lamin A/C in CD4+ T-cells control intestinal homeostasis and can cause inflammatory bowel disease (IBD) are unknown. Here, we explore lamin A/C in a mouse model of IBD. Adoptive transfer to Rag1-/- mice of Lmna-/- CD4+ T-cells, which have enhanced regulatory T-cells (Treg) differentiation and function, induced less severe IBD than wild-type T-cells. Lamin A/C deficiency in CD4+ T-cells enhanced transcription of the Treg master regulator FOXP3, thus promoting Treg differentiation, and reduced Th1 polarization, due to epigenetic changes in the Th1 master regulator T-bet. In mesenteric lymph nodes, retinoic acid (RA) released by CD103+ dendritic cells downregulated lamin A/C in CD4+ T-cells, enhancing Treg differentiation. However, non-RA-producing CD103- dendritic cells predominated in peripheral lymph nodes, facilitating lamin A/C expression in CD4+ T-cells and therefore Th1 differentiation. Our findings establish lamin A/C as a key regulator of Th differentiation in physiological conditions and show it as a potential immune-regulatory target in IBD. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.This study was supported by grants to PC from the Research Council of Norway, to JMG-G from ISCIII (PI14/00526; PI17/01395; CP11/00145; CPII16/00022; EuroCellNet COST Action CA15214), the Miguel Servet Program and Fundación Ramón Aréces; to VA (RD12/0042/0028 SAF2013-46663-R, SAF2016-79490-R); to FS-M (SAF2017-82886-R; ERC-2011-AdG 294340-GENTRIS, CIBER CARDIOVASCULAR, PIE 13.0004-BIOIMID and CAM-B2017/BMD-3671-INFLAMUNE), to GC and JLP (PI16/00032 and RETICs RD16/0012 RIER), and to JV (BIO2015-67580-P; PRB3, IPT17/0019 - ISCIII-SGEFI/ERDF, ProteoRed) with co-funding from the European Regional Development Fund (ERDF) “Una manera de hacer Europa”. The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia, Innovación y Universidades (MCNU) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505). RTF is supported by the Fundación Ramón Aréces, VZG by ISCIII, BHF by the Instituto de Investigación Hospital 12 de Octubre (i+12), and JMG-G by the ISCIII Miguel Servet Program, i+12 and Universidad Autónoma de Madrid (UAM).S