Thymic Stromal Lymphopoietin in nasal polyposis

Introduction:

Nasal polyposis is considered to be the end stage of mucosal inflammation. Nasal polyposis doesnt contribute siginficantly to the mortality, but causes a significant reduction in the quality of life of the patient. The development of nasal polyposis is associated with:

1. Chronic inflammation
2. Allergic responses
3. Autonomic nervous system dysfunction
4. Genetic predisposition

This article discusses the role played by Thymic stromal lymphopoietin in the pathogenesis of nasal polyposis.

Thymic stromal lymphopoietin is actually a protein belonging to the cytokine family. This protein activates the antigen presenting cells which is of paramount importance in the maturation process of T cell population. This protein is secreted by fibroblasts, epithelial cells, stromal cells. Studies have demonstrated that this protein is secreted by non haemopoeitic cells.

Maturation of Helper T cells Type II is hastened by the presence of Thymic stromal lymphopoietin. These Helper T cells play a vital role in the pathogenesis of nasal polyposis.

How exactly thymic stromal lymphopoietin hastens the maturation process of Helper Type II T cells?

Nasal epithelium secretes thymic stromal lymphopoietin. This protein binds on the special receptor on the surface of dendritic cells. This binding causes release of OX40 ligand. This OX40 ligand causes the helper T cells to mature. These mature helper T cells secrete IL-4 and tumor necrosis factor alpha which are the well documented inflammatory mediators which could lead to the formation of nasal polyposis.