TGFB1 and allergic asthma: Therefore, to assess whether IL-12αC96S and EBI3 can modulate proinflammatory cytokine production by myeloid cells, we isolated CD14+ monocytes from PBMCs, differentiated them into alveolar-like macrophages by stimulation with granulocyte-macrophage colony-stimulating factor (GM-CSF) and transforming growth factor–β (TGF-β; Fig. 4B) (47, 48), and treated them with house dust mite extract (HDM), one of the most frequent triggers of allergic asthma.