The avascular cornea is a protective barrier with intact innate immune, but restricted adaptive immune response for optimal vision. Surgery, injury and infection of the cornea can disrupt this balance between innate and adaptive immune response leading to intense inflammation and loss of vision. We found lumican, an abundant extracellular matrix (ECM) stromal proteoglycan, to regulate corneal immune functions. Lumican itself binds LPS that can be removed competitively by CD14, the cell surface protein that transfers LPS to toll-like receptor 4, the trans-membrane IPS receptor. Mice, deficient in lumican (Lum-/-), are hypo-responsive to bacterial lipopolysacharide endotoxin (LPS), and produce lower amounts of proinflammatory cytokines. More importantly, in LPS-induced corneal keratitis, the Lum-/- mice show reduced neutrophil influx early, but overall delayed healing. Thus, innate immune response is impaired in our Lum-/- mice. Lumican also binds FasL and TGFbeta, and in the Lum-/- mice these pathways are disrupted. The Fas-FasL mediated apoptosis and TGFbeta signaling in the cornea help to maintain an immunosuppressive environment for immune privilege. Our overarching hypothesis is that in the cornea lumican promotes early innate immune response, but provides an immunosuppressive microenvironment to restrict adaptive immunogenic mechanisms to maintain immune privilege. The following aims will test this hypothesis. 1) Test if lumican regulates corneal inflammation and immune privilege such that Lum-/-corneal allografts have decreased survival. Test if lumican regulates bone marrow cell (BMC) functions directly by evaluating allograft success in Lum+/+ and Lum-/- BMC chimera hosts. 2) Test if lumican promotes corneal innate immune response via the LPS-specific CD14-TLR4 pathway, a) in cell culture by assessing the ability of recombinant lumican to rescue LPS-induction of TNFa in Lum-/- macrophages also lacking CD14, and b) by comparing LPS-induced keratitis in Lum+/+ and Lum-/- BMC CD14-null chimeras and parental strains. 3) Investigate connections between lumican and the TLR4-signaling pathway and its therapeutic implications. Test binding of lumican-derived synthetic peptides to LPS and their ability to regulate innate immune response in macrophage culture and their effects on LPS-induced keratitis. This study will elucidate a novel link between the ECM and corneal immune functions and lead to the development of therapeutic lumican-products to alleviate detrimental inflammatory responses in the cornea, a major focus of the National Eye Institute.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY011654-16
Application #
8302366
Study Section
Anterior Eye Disease Study Section (AED)
Program Officer
Mckie, George Ann
Project Start
1997-01-01
Project End
2013-12-31
Budget Start
2012-08-01
Budget End
2013-12-31
Support Year
16
Fiscal Year
2012
Total Cost
$389,664
Indirect Cost
$152,064
Name
Johns Hopkins University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
001910777
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Frikeche, Jihane; Maiti, George; Chakravarti, Shukti (2016) Small leucine-rich repeat proteoglycans in corneal inflammation and wound healing. Exp Eye Res 151:142-9
Stasiak, Marta; Boncela, Joanna; Perreau, Corinne et al. (2016) Lumican Inhibits SNAIL-Induced Melanoma Cell Migration Specifically by Blocking MMP-14 Activity. PLoS One 11:e0150226
Hultgårdh-Nilsson, A; Borén, J; Chakravarti, S (2015) The small leucine-rich repeat proteoglycans in tissue repair and atherosclerosis. J Intern Med 278:447-61
Dupuis, Loren E; Berger, Matthew G; Feldman, Samuel et al. (2015) Lumican deficiency results in cardiomyocyte hypertrophy with altered collagen assembly. J Mol Cell Cardiol 84:70-80
Gowda, Ranjita N; Redfern, Rachel; Frikeche, Jihane et al. (2015) Functions of Peptidoglycan Recognition Proteins (Pglyrps) at the Ocular Surface: Bacterial Keratitis in Gene-Targeted Mice Deficient in Pglyrp-2, -3 and -4. PLoS One 10:e0137129
Foster, James; Wu, Wai-Hong; Scott, Sherri-Gae et al. (2014) Transforming growth factor β and insulin signal changes in stromal fibroblasts of individual keratoconus patients. PLoS One 9:e106556
Chen, Shoujun; Young, Marian F; Chakravarti, Shukti et al. (2014) Interclass small leucine-rich repeat proteoglycan interactions regulate collagen fibrillogenesis and corneal stromal assembly. Matrix Biol 35:103-11
Steinhart, Matthew R; Cone-Kimball, Elizabeth; Nguyen, Cathy et al. (2014) Susceptibility to glaucoma damage related to age and connective tissue mutations in mice. Exp Eye Res 119:54-60
Chaerkady, Raghothama; Shao, Hanjuan; Scott, Sherri-Gae et al. (2013) The keratoconus corneal proteome: loss of epithelial integrity and stromal degeneration. J Proteomics 87:122-31
Shao, Hanjuan; Scott, Sherri-Gae; Nakata, Chiaki et al. (2013) Extracellular matrix protein lumican promotes clearance and resolution of Pseudomonas aeruginosa keratitis in a mouse model. PLoS One 8:e54765

Showing the most recent 10 out of 36 publications