Localization of IL-4 and IL-5 mRNA in Bronchial Biopsies

Cytokines are important biochemical mediators essential in initiating and maintaining inflammatory reactions associated with allergic disease in man. Although cytokines can be secreted from a variety of different cell types, considerable attention has been focused on T-lymphocyte-derived cytokines, which have been clearly implicated in the modulation of the immune system. Bronchial asthma is associated with persistent infiltration of the airways with activated CD4⁺ T-lymphocytes, as well as other inflammatory cells exhibiting a T-helper type-2 (Th2)-like cytokine profile (1 –3 ).