To Dry Eye Disease Non Sjogrens Dry

Inflammatory affections in dry eye disease are not only found in the lacrimal gland. Even in the clinically inflammation free and primary tear deficient non-Sjogren's dry eye an elevation of inflammatory cytokines (ILia, IL6, IL8, TNFa) is found in the tear film and inside the tissue of the conjunctiva [48]. The ability of conjunctival epithelial cells to release inflammatory cy-tokines has been reported [12]. This indicates a shift of the cellular immune response into the direction of an inflammatory Thi response similar to the inflammatory affections in the lacrimal gland and may similarly lead to a destruction of the epithelium and the underlying extracellular matrix [48,58]. The primary affection seems to lie in the epithelial cells, similarly to the lacrimal gland, but also in the conjunctiva an upregulation of inflammatory markers that indicate an activation of the mucosal lymphocytes was recently described [59].

Protective factors such as growth factors (EGF, HGF) that are responsible for the proliferation but even more for the mature differentiation of the tissue may at the same time be downregulated [48]. Consequently in dry eye syndromes a hyperproliferation of the conjunc-tival epithelium is observed combined with impaired differentiation. This is conceivably driven by the presence of inflammatory cytokines and the relative inhibition of cell differentiation is due to diminished growth factors. The con-junctival epithelium in dry eye shows an immature phenotype of the apical cells with a basal cell type cytokeratin pattern and an absence of integral epithelial surface mucins [48, 49], which in turn diminishes the adherence of the tear film to the ocular surface and hence reduces the tear film stability.

Elevated inflammatory cytokines further induce an upregulation of proteases (matrix met-alloproteinases) in the tissue and tearfilm, which indicates additional degenerative remodelling of the connective tissue of the mucosal lamina propria at the ocular surface [13,31,36]. Inflammatory cytokines can also impair ocular surface innervation in the sense that they inhibit sensory information about ocular dryness to reach the central nervous system in order to elicit efferent secretomotor impulses in glandular tissue. The neural reflex arc is thereby interrupted, leading to a further decrease of secretion and potentially inducing neurogenic inflammation of the lacrimal gland also in primary non-Sjogren's dry eyes [58].

How To Deal With Rosacea and Eczema

How To Deal With Rosacea and Eczema

Rosacea and Eczema are two skin conditions that are fairly commonly found throughout the world. Each of them is characterized by different features, and can be both discomfiting as well as result in undesirable appearance features. In a nutshell, theyre problems that many would want to deal with.

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