|
1
|
Edman MC, Janga SR, Meng Z, Bechtold M, Chen AF, Kim C, Naman L, Sarma A, Teekappanavar N, Kim AY, Madrigal S, Singh S, Ortiz E, Christianakis S, Arkfeld DG, Mack WJ, Heur M, Stohl W, Hamm-Alvarez SF. Increased Cathepsin S activity associated with decreased protease inhibitory capacity contributes to altered tear proteins in Sjögren's Syndrome patients. Sci Rep 2018; 8:11044. [PMID: 30038391 PMCID: PMC6056496 DOI: 10.1038/s41598-018-29411-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 07/11/2018] [Indexed: 02/08/2023] Open
Abstract
Cathepsin S (CTSS) activity is elevated in Sjögren's Syndrome (SS) patient tears. Here we tested whether protease inhibition and cystatin C (Cys C) levels are reduced in SS tears, which could lead to enhanced CTSS-driven degradation of tear proteins. CTSS activity against Cys C, LF and sIgA was tested in SS or healthy control tears. Tears from 156 female subjects (33, SS; 33, rheumatoid arthritis; 31, other autoimmune diseases; 35, non-autoimmune dry eye (DE); 24, healthy controls) were analyzed for CTSS activity and Cys C, LF, and sIgA levels. Cys C and LF showed enhanced degradation in SS tears supplemented with recombinant CTSS, but not supplemented healthy control tears. CTSS activity was significantly increased, while Cys C, LF and sIgA levels were significantly decreased, in SS tears compared to other groups. While tear CTSS activity remained the strongest discriminator of SS in autoimmune populations, combining LF and CTSS improved discrimination of SS beyond CTSS in DE patients. Reductions in Cys C and other endogenous proteases may enhance CTSS activity in SS tears. Tear CTSS activity is reconfirmed as a putative biomarker of SS in an independent patient cohort while combined LF and CTSS measurements may distinguish SS from DE patients.
Collapse
Affiliation(s)
- Maria C Edman
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Srikanth R Janga
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Zhen Meng
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, Los Angeles, University of Southern California, Los Angeles, CA, USA
| | - Mercy Bechtold
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Alexander F Chen
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Chongiin Kim
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Luke Naman
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Arunava Sarma
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Neha Teekappanavar
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Alice Y Kim
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Sara Madrigal
- Division of Rheumatology, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Simranjit Singh
- Division of Rheumatology, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Elizabeth Ortiz
- Division of Rheumatology, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Stratos Christianakis
- Division of Rheumatology, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Daniel G Arkfeld
- Division of Rheumatology, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Wendy J Mack
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Martin Heur
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - William Stohl
- Division of Rheumatology, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Division of Rheumatology, Department of Medicine, Los Angeles County + University of Southern California Medical Center, Los Angeles, CA, USA
| | - Sarah F Hamm-Alvarez
- Department of Ophthalmology, USC Roski Eye Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, Los Angeles, University of Southern California, Los Angeles, CA, USA.
| |
Collapse
|