IL4 and hypersensitivity pneumonitis: Moreover, typical for VD3-deficient mice with HP, there was also an increased influx of immune cells into the lungs (especially neutrophils, macrophages, dendritic cells and lymphocytes Tc), a disturbed cytokine profile with over-production of growth factors favoring fibrosis (FGF2 and TGFβ), and lowered synthesis of several cytokines (IL1β, IL6, IL12, IL4 IL10, IL13).