Anterior Uveitis

Anterior Uveitis (AU)

Anterior uveitis (AU) is one of the most common types of ocular inflammation that occurred in the uveal tract, including the iris, anterior part of ciliary body or both. Iridocyclitis and iritis are two typical subtypes of AU. The inflammation of iridocyclitis gives priority to the ciliary body, along with iris, while iritis is the inflammation of the anterior chamber and iris. In anterior uveitis patients, excessive infiltration of neutrophils, macrophages, and lymphocytes can cause permanent damage to the ocular tissue. According to its clinical course, clinical appearance, granulomatous or non-granulomatous, infectious or non-infectious etc., anterior uveitis is classified as acute or chronic anterior uveitis.

Symptoms and Signs of Anterior Uveitis

1. Red, sore and inflamed eye
2. Burning of the eye
3. Blurred vision
4. Sensitivity to light
5. Irregular-shaped pupil
6. Blacked out sclera
7. Dark spots in the visual
8. Headaches
9. Dilated ciliary vessels
10. Cells and flare in the anterior chamber
11. Keratic precipitate
12. Busacca nodules

Fig. 1 Uveitis results from imbalance between inflammatory mechanisms and regulatory mechanisms.^{1, 2}

Without effective and timely treatment, AU may lead to severe complication (glaucoma, cataract or retinal edema, etc.), compared with permanent ocular damage and loss of vision. AU is responsible for the rise of intraocular pressure, which may lead to glaucoma. Moreover, cystoid macular edema (CME) is proved to be associated with the AU-caused fluid accumulation in the macula.

Causes of Anterior Uveitis

The exact pathogenesis of AU is not clear, while there is a diverse set of accepted etiologies that span a wide spectrum of genetic, infectious and noninfectious causes.

1. Immune-mediated (noninfectious) Causes

Th17 T cell sub-population that bear T-cell receptors is activated in AU patients. To prevent the autoreactivity of T cells and protect the eyes, microglia and dendritic cells in the eye produce a large amount of TGF-β and other suppressive cytokines, including IL-10.

1. Genetic Factors

There are some strong genetic factors that predispose the anterior uveitis onset including HLA-B27 (a class I major histocompatibility complex) and the PTPN22 genotype. HLA-B27 is closely associated with ankylosing spondylitis, which is a chronic systemic disease characterized by inflammation of both sacroiliac joints and the spine, and the most common extra-articular manifestation is anterior uveitis.

1. Infectious Causes

Strong evidence has pointed to reactivation of viruses (herpes simplex, varicella zoster, etc.) parasites, and fungi as important causes of anterior uveitis. Bacterial infection is another significant contributing factor in the pathogenesis of AU.

1. Complement

Complement and complement regulatory proteins (CRegs) in the pathogenesis of anterior uveitis have been addressed and recognized, especially C3 and complement receptor 3 (CR3). The presence of complement was critical for local production of cytokines (IFN-γ and IL-10), chemokines (IP-10), and adhesion molecules (ICAM-1 and LECAM-1) in anterior uveitis.

Creative Biolabs has established advanced Complement Therapeutics Platform including antibody engineering platform, protease inhibitor platform, and drug discovery platform, and is equipped to offer a full range of biotherapeutics development services regarding drug discovery and validation for anterior uveitis. If you are interested, please contact us for detailed information.

References

1. Mérida, Salvador, et al. "New immunosuppressive therapies in uveitis treatment." International journal of molecular sciences 16.8 (2015): 18778-18795.
2. under Open Access license CC BY 4.0, without modification.

Related Product

• Age-Related Macular Degeneration