Cytokines in Allergic Conjunctivitis: Unraveling Their Pathophysiological Roles.

Allergic conjunctivitis is one of the common immune hypersensitivity disorders that affect the ocular system. The clinical manifestations of this condition exhibit variability contingent upon environmental factors, seasonal dynamics, and genetic predisposition. While our comprehension of the pathophysiological engagement of immune and nonimmune cells in the conjunctiva has progressed, the same cannot be asserted for the cytokines mediating this inflammatory cascade. In this review, we proffer a comprehensive description of interleukins 4 (IL-4), IL-5, IL-6, IL-9, IL-13, IL-25, IL-31, and IL-33, as well as thymic stromal lymphopoietin (TSLP), elucidating their pathophysiological roles in mediating the allergic immune responses on the ocular surface. Delving into the nuanced functions of these cytokines holds promise for the exploration of innovative therapeutic modalities aimed at managing allergic conjunctivitis.

Vernal Keratoconjunctivitis: Immunopathological Insights and Therapeutic Applications of Immunomodulators.

Vernal keratoconjunctivitis (VKC) is a complex and multifactorial disease process that employs Th2 cell-mediated immunologic processes, which involves the overexpression of interleukin 4 (IL-4), IL-5, IL-9, IL-13, and IL-31, and the activation of mast cells that release IL-5 and CCL-11, recruiting eosinophils to the site of inflammation. The disease primarily affects young males and is more common in regions with warm climates. VKC is characterized by persistent and recurrent conjunctival inflammation that can adversely affect the patient's quality of life, and, when inadequately treated, may lead to a host of ocular complications, such as corneal shield ulcers and scarring. The major distinct forms of VKC include limbal or palpebral, which may occur in combination. The clinicopathological features of VKC include the presence of pseudogerontoxon, limbal gelatinous hyperplasia, and perilimbal hyperpigmentation. Topical immunomodulators are effective anti-steroidal options for controlling severe and chronic cases of VKC. This review will provide a brief overview of topical immunomodulators, including cyclosporin and tacrolimus, and will highlight the clinical manifestations, pathological mechanisms, and fibroproliferative changes in the conjunctiva that can result from recurrent disease.