CD4 and asthma: Previous observations that mild steroid-naive asthma is characterized by a bias toward type 2 inflammation were confirmed, with increased numbers of IL-13–secreting CD4+ (TH2) cells in sputum, BAL fluid, and endobronchial biopsy specimens from patients with mild asthma (Fig 1, A) and ratios of IL-13– to IFN-γ–secreting CD4+ (TH1) cells (see Fig E3 in this article's Online Repository at www.jacionline.org).