Macrophage polarization and M1/M2 balance play an important role in anti-microbial defense, asthma and allergy, fibrosis, wound healing, and autoimmunity.26 To validate the existence of two different macrophages, immunofluorescence staining of CD68, S100A8, and CD163 was performed (Fig. 3j). Here, S100A8 is linked to Allergy.