Protein profiles of Rlow and Rhigh analyzed by SDS-PAGE and Western blotting. SDS-PAGE (A, B, and C) and Western blotting (D, E, and F) demonstrate that three proteins were clearly absent (A, C, D, and F) or aberrant (D and E) in Rhigh. Arrows indicate the presence or absence of the implicated proteins, and pertinent molecular masses are noted. Western blot analysis was performed with anti-fibronectin (D), anti-HMW3 (E), and anti-PlpA (F).