Biology subjects

Seo, G.-Y.

Publications and source records attributed to Seo, G.-Y..

3 recordsLinked to original sources

bioRxiv2021

HVEM structures and mutants reveal distinct functions of binding to LIGHT and BTLA/CD160

HVEM is a TNF (tumor necrosis factor) receptor contributing to a broad range of immune functions involving diverse cell types. It interacts with a TNF ligand, LIGHT, and immunoglobulin (Ig) superfamily members BTLA and CD160. Assessing the functional impact of HVEM binding to specific ligands in different settings has been complicated by the multiple interactions of HVEM and HVEM binding partners. To dissect the molecular basis for multiple functions, we determined crystal structures that reveal the distinct HVEM surfaces that engage LIGHT or BTLA/CD160, including the human HVEM:LIGHT:CD160 ternary complex, with HVEM interacting simultaneously with both binding partners. Based on these structures, we generated mouse HVEM mutants that selectively recognized either the TNF or Ig ligands in vitro. Knock-in mice expressing these muteins maintain expression of all the proteins in the HVEM network, yet they demonstrate selective functions for LIGHT in the clearance of bacteria in the intestine and for the Ig ligands in the amelioration of liver inflammation.

immunology↗

bioRxiv2020

Transcriptome and Chromatin Landscape of iNKT cells are Shaped by Subset Differentiation and Antigen Exposure

Invariant natural killer T cells (iNKT cells) differentiate into thymic and peripheral NKT1, NKT2 and NKT17 subsets. We determined if the gene programs associated with these thymic subsets were maintained in peripheral sites, the influence of tissue location, and if there were large-scale changes after antigen exposure. RNA-seq and ATAC-seq analyses showed that iNKT cells in any subset were similar, regardless of tissue location. Lung iNKT cell subsets possessed the most distinct location-specific features, shared with other innate lymphocytes in the lung, possibly consistent with increased activation. After antigenic stimulation, iNKT cells underwent chromatin and transcription changes leading to two populations: one similar to follicular helper T cells and the other like NK or effector cells. Phenotypic analysis indicated these changes were observed long-term, suggesting that iNKT cells gene programs are not fixed, but they are capable of chromatin remodeling after antigen to give rise to several new subsets.

immunology↗

bioRxiv2020

Epithelial HVEM promotes basement membrane synthesis and intraepithelial T cell survival and migration

Intraepithelial T cells (IET) provide continuous surveillance of the intestinal epithelium, but little was known about how epithelial-derived signals regulate the IET population. We show that epithelial expression of the herpes virus entry mediator (HVEM), a member of the TNF receptor superfamily (TNFRSF), maintained the survival of small intestine IET, especially innate-like TCR{beta}+ cells lacking CD4 and CD8{beta}. Patrolling movement of all CD8+ IET also was impaired in the absence of HVEM. HVEM-deficient epithelial cells exhibited downregulation of synthesis of basement membrane components, including collagen IV. Collagen IV supported IET survival in vitro via interactions with {beta}1 integrins expressed by the IET; absence of {beta}1 integrins decreased some IET subsets. Therefore, these data define a circuit whereby epithelial cells regulate intestine resident T lymphocyte populations through basement membrane synthesis.

immunology↗