Toll-like receptor-associated keratitis and strategies for its management

Abstract

Keratitis is an inflammatory condition, characterized by involvement of corneal tissues. Most recurrent challenge of keratitis is infection. Bacteria, virus, fungus and parasitic organism have potential to cause infection. TLR are an important class of protein which has a major role in innate immune response to combat with pathogens. In last past years, extensive research efforts have provided considerable abundance information regarding the role of TLR in various types of keratitis. This paper focuses to review the recent literature illustrating amoebic, bacterial, fungal and viral keratitis associated with Toll-like receptor molecules and summarize existing thoughts on pathogenesis and treatment besides future probabilities for prevention against TLR-associated keratitis.

Genome-Wide Association Analysis for Chronic Superficial Keratitis in the Australian Racing Greyhound

“…TLR8 is a part of a group of TLR genes that responds to nucleic acids, and particularly single-stranded RNAs (for example, viruses). In addition to a non-specific connection with autoimmune responses, TLR genes have been specifically connected with ocular keratitis in humans [ 15 ].…”

“…It is possible that an external agent may precipitate the primary lesion, triggering an alteration in the ocular immune response to self [ 14 ]. In humans, ocular keratitis may be precipitated by viruses [ 15 ]. Regardless of the initiating cause, it is very likely that a pathological immune response is responsible for the opacity and neovascularization that together characterize the CSK disorder.…”

The Existence of Periodontal Disease and Subsequent Ocular Diseases: A Population-Based Cohort Study

“…Besides, the elevation of certain inflammatory cytokines like interleukin and matrix metalloproteinase has also been found in ocular diseases including keratitis and uveitis [ 26 , 27 ], and the oxidative stress would also be raised in inflammatory eye diseases [ 28 ]. Moreover, the activation of Toll-like receptors was found in both PD and ocular diseases involving the anterior uveitis and keratitis [ 29 , 30 , 31 ], which implies a similar involvement of innate immunity that could be due to both infection and inflammation. Accordingly, it is possible that the microorganisms involved PD transfer into the ocular region and induce infection via the route of either the cavernous sinus–ophthalmic vein or the anastomosis of anterior ethmoidal artery–posterior ethmoidal artery–sphenopalatine artery, and the elevated inflammation and oxidative stress of PD could influence nearby tissue like the eye.…”

The Role of SREC-Ⅰ in Innate Immunity to Aspergillus fumigatus Keratitis

“…The innate immune system provides the first line of defense to recognize and resist pathogens against fungal infection, and the pattern recognition receptors play a vital role in innate immunity, 4 including Toll-like receptors (TLRs), C-type lectin-like receptors, and the scavenger receptor family. [5][6][7][8] Scavenger receptor expressed by endothelial cell-Ⅰ (SREC-Ⅰ) is a member of scavenger receptor family F, known as SCARF-Ⅰ. 9 It is an 86-kDa protein with an extended extracellular domain and first cloned from human umbilical vein endothelial cells.…”

“…The innate immune system provides the first line of defense to recognize and resist pathogens against fungal infection, and the pattern recognition receptors play a vital role in innate immunity, 4 including Toll-like receptors (TLRs), C-type lectin-like receptors, and the scavenger receptor family. 5 – 8 …”