Figure 3. Immunolocalization of ALDH3A1, PDIA3, and PRDX2 in pterygium. Immunohistochemistry assay showed the presence of ALDH3A1, PDIA3, and PRDX2 preferentially in the cytoplasm of the basal epithelium of the pterygium. Meanwhile, there was only faintly positive immunostaining of these proteins in the healthy conjunctiva.