It has been suggested that different serum cytokines, namely, interleukin (IL)-4, IL-5, and IL-13 for ABPA and IL-1β, IL-10, tumor growth factor-β, and soluble CD40 ligand (sCD40L) for CPA, are involved in pathology, and these serum cytokine profiles may be useful in differentiating between the two diseases [15,16,17]. The gene discussed is CD40LG; the disease is allergic bronchopulmonary aspergillosis.