Immunohistochemical localization of placental GAGs. Frozen sections were incubated with chondroitin ABC–lyase (A), B-lyase (B), AC II–lyase (C), heparitinase (E), or buffer alone (D,F) and then stained with ΔDi-4S antibody (A-D) or Δ-HS antibody (E,F). V indicates vessel; S, stroma; and T (arrowheads), syncytiotrophoblast layer. Original magnification, 400 ×.