It is well established that leukocyte infiltration of the central nervous system (CNS) is a critical early step in the development of the demyelinating autoimmune disease, multiple sclerosis (MS) however the mechanistic details of this process remain poorly understood. Blocking leukocyte infiltration and destruction of the CNS in a targeted manner remains a significant clinical challenge. The long-term objectives are to develop therapeutics that restore immune tolerance and control autoimmune-mediated destruction of target organs. The obiective of this proposal is to define how stromal cells regulate autoimmune inflammation of the CNS. Stromal cells create inflammatory microenvironments, attract T cells and antigen presenting cells (APCs) into the CNS, create three-dimensional reticular structures that infiltrating leukocytes crawl on, and produce proinflammatory cytokines through interactions with Th17 cells. Moreover, stromal cells can function as APCs and regulate the function of activated T cells in close proximity. The central hvpothesis is that a stromal cell network is essential for the formation of chronic inflammatory lesions in MS. This hypothesis is based on emerging evidence from the literature and preliminary data generated in the applicants'laboratories. The rationale for the proposed research is that elucidating the mechanisms by which stromal cells interact with T cells and APCs at the blood brain barrier and in the CNS parenchyma may illuminate mechanistic insight into this pathogenic process.
Two specific aims will be carried out to test this hypothesis: 1) Define the role of PDPN expression by stromal, cells in leukocyte infiltration of the CNS. and 2) Elucidate the impact of stromal cell-leukocyte cross-talk in the inflamed CNS. As part of the first aim, human brain tissue from MS patients and healthy subjects will be studied to evaluate the interactions between leukocytes and PDPN-expressing stromal cells in lesions. In addition, novel conditional knockout mice will be used to evaluate whether PDPN expression by stromal cells and CLEC-2 expression by dendritic ceils and B ceils affects leukocytic infiltration of the CNS during EAE. In the second aim the impact of autoimmune tissue inflammation on stromal cell interactions with T cells and APCs will be evaluated. Furthermore, the mechanism by which the inflammatory milieu converts FRCs from immunosuppressive to proinflammatory cells will be interrogated. The proposed research is innovative because the contribution of stromal cells to the pathogenesis of MS is an understudied field and the role ofthe PDPN-CLEC-2 axis in leukocyte infiltration of inflamed tissues has not been previously addressed. The study is significant because elucidation ofthe mechanisms by which stromal cells influence APC and T cell function may offer new opportunities for intervention.

Public Health Relevance

Stromal cells create inflammatory microenvironments, attract T cells and antigen presenting cells (APCs) into the central nervous system, create three-dimensional reticular structures that infiltrating leukocytes crawl on, and produce proinflammatory cytokines through interactions with Thi 7 cells. Moreover, stromal cells can function as APCs and regulate the function of activated T cells in close proximity. The contribution of stromal cells to the pathogenesis of multiple sclerosis is an understudied field, and elucidation of the mechanisms by which they interact with APCs and T cells may offer new opportunities for intervention.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Program Projects (P01)
Project #
5P01AI045757-16
Application #
8705346
Study Section
Special Emphasis Panel (ZAI1)
Project Start
Project End
Budget Start
2014-09-01
Budget End
2015-08-31
Support Year
16
Fiscal Year
2014
Total Cost
Indirect Cost
Name
Dana-Farber Cancer Institute
Department
Type
DUNS #
City
Boston
State
MA
Country
United States
Zip Code
02215
Ito, Yoshinaga; Ashenberg, Orr; Pyrdol, Jason et al. (2018) Rapid CLIP dissociation from MHC II promotes an unusual antigen presentation pathway in autoimmunity. J Exp Med 215:2617-2635
Ponath, Gerald; Lincoln, Matthew R; Levine-Ritterman, Maya et al. (2018) Enhanced astrocyte responses are driven by a genetic risk allele associated with multiple sclerosis. Nat Commun 9:5337
Sumida, Tomokazu; Lincoln, Matthew R; Ukeje, Chinonso M et al. (2018) Activated ?-catenin in Foxp3+ regulatory T cells links inflammatory environments to autoimmunity. Nat Immunol 19:1391-1402
Cremasco, Viviana; Astarita, Jillian L; Grauel, Angelo L et al. (2018) FAP Delineates Heterogeneous and Functionally Divergent Stromal Cells in Immune-Excluded Breast Tumors. Cancer Immunol Res 6:1472-1485
Meyer Zu Horste, Gerd; Przybylski, Dariusz; Schramm, Markus A et al. (2018) Fas Promotes T Helper 17 Cell Differentiation and Inhibits T Helper 1 Cell Development by Binding and Sequestering Transcription Factor STAT1. Immunity 48:556-569.e7
Gee, Marvin H; Sibener, Leah V; Birnbaum, Michael E et al. (2018) Stress-testing the relationship between T cell receptor/peptide-MHC affinity and cross-reactivity using peptide velcro. Proc Natl Acad Sci U S A 115:E7369-E7378
Kim, Yong Chan; Zhang, Ai-Hong; Yoon, Jeongheon et al. (2018) Engineered MBP-specific human Tregs ameliorate MOG-induced EAE through IL-2-triggered inhibition of effector T cells. J Autoimmun 92:77-86
Lucca, Liliana E; Hafler, David A (2017) Resisting fatal attraction: a glioma oncometabolite prevents CD8+ T cell recruitment. J Clin Invest 127:1218-1220
Nylander, Alyssa N; Ponath, Gerald D; Axisa, Pierre-Paul et al. (2017) Podoplanin is a negative regulator of Th17 inflammation. JCI Insight 2:
Gierahn, Todd M; Wadsworth 2nd, Marc H; Hughes, Travis K et al. (2017) Seq-Well: portable, low-cost RNA sequencing of single cells at high throughput. Nat Methods 14:395-398

Showing the most recent 10 out of 129 publications