Characterization of GDF5 expression by the GDF5-CHO cell line in vivo and of the immune response of the host striatum to GDF5-CHO cell transplantation. (A)–(D) Representative photomicrographs showing (A) CD 8, (B) MHC I, (C) MHC II and (D) IgM immunoreactivity at the graft sites at 10 days after intrastriatal grafting of CHO cells. Graphical representation of the extent of the immunoreactivity to (E) CD 4, (F) CD 8, (G) MHC I, (H) MHC II, (I) IgM and (J) Ed 1 in the adult rat striatum at 5, 10, 21 and 42 days after grafting of E14 VM cells, or CHO cells with or without oral CyA, as indicated. (K)–(N) Representative photomicrographs showing intrastriatal transplants of mock-CHO cells and GDF5-CHO cells at 1 and 7 days post-grafting, as indicated, immunocytochemically stained for GDF5 using aMP5 antibody. Scale bar = 100 μm.