Tear biomarkers in dry eye disease: Progress in the last decade.

Content Provider	Europe PMC
Author	Kumar, Nimisha R Praveen, Machiraju Narasimhan, Raghav Khamar, Pooja D’Souza, Sharon Sinha-Roy, Abhijit Sethu, Swaminathan Shetty, Rohit Ghosh, Arkasubhra
Copyright Year	2023
Abstract	Dry eye disease (DED) is a commonly occurring, multifactorial disease characterized by reduced tear film stability and hyperosmolarity at the ocular surface, leading to discomfort and visual compromise. DED is driven by chronic inflammation and its pathogenesis involves multiple ocular surface structures such as the cornea, conjunctiva, lacrimal glands, and meibomian glands. The tear film secretion and its composition are regulated by the ocular surface in orchestration with the environment and bodily cues. Thus, any dysregulation in ocular surface homeostasis causes an increase in tear break-up time (TBUT), osmolarity changes, and reduction in tear film volume, all of which are indicators of DED. Tear film abnormalities are perpetuated by underlying inflammatory signaling and secretion of inflammatory factors, leading to the recruitment of immune cells and clinical pathology. Tear-soluble factors such as cytokines and chemokines are the best surrogate markers of disease severity and can also drive the altered profile of ocular surface cells contributing to the disease. Soluble factors can thus help in disease classification and planning treatment strategies. Our analysis suggests increased levels of cytokines namely interleukin-1β (IL-1β), IL-2, IL-4, IL-6, IL-9, IL-12, IL-17A, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α); chemokines (CCL2, CCL3, CCL4, CXCL8); MMP-9, FGF, VEGF-A; soluble receptors (sICAM-1, sTNFR1), neurotrophic factors (NGF, substance P, serotonin) and IL1RA and reduced levels of IL-7, IL-17F, CXCL1, CXCL10, EGF and lactoferrin in DED. Due to the non-invasive sample collection and ease of quantitively measuring soluble factors, tears are one of the best-studied biological samples to molecularly stratify DED patients and monitor their response to therapy. In this review, we evaluate and summarize the soluble factors profiles in DED patients from the studies conducted over the past decade and across various patient groups and etiologies. The use of biomarker testing in clinical settings will aid in the advancement of personalized medicine and represents the next step in managing DED.
ISSN	03014738
Journal	Indian Journal of Ophthalmology
Volume Number	71
PubMed Central reference number	PMC10276712
Issue Number	4
PubMed reference number	37026250
e-ISSN	19983689
DOI	10.4103/ijo.ijo_2981_22
Language	English
Publisher	Wolters Kluwer - Medknow
Publisher Date	2023-04-01
Publisher Place	India
Access Restriction	Open
Rights License	This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms. Copyright: © 2023 Indian Journal of Ophthalmology
Subject Keyword	Biomarker chemokines cytokines dry eye disease growth factors tear-soluble factors
Content Type	Text
Resource Type	Article
Subject	Ophthalmology