The main features of allergic asthma are increases in the numbers and activity of airway mast cells and eosinophils which are due to the pathophysiological effects of proinflammatory cytokines such as interleukin- (IL-) 4, IL-5, and IL-13 released by activated CD4+ T-cells (Th2 cells) in response to environmental allergens [3]. Here, CD4 is linked to allergic asthma.