Expression of the transduced lacZ gene mediated by recombinant AAV- and B19-lacZ vectors in human 293 and Epo-differentiated MB-02 cells. Approximately equivalent numbers of 293 cells (A, B, and C) and Epo-differentiated MB-02 cells (D, E, and F) were either mock infected or infected with 200 particles of AAV-lacZ (B and E) and B19-lacZ (C and F) recombinant vectors per cell under identical conditions. Forty-eight hours postinfection, the cells were fixed and stained for analysis of expression of the lacZ gene, as described in Materials and Methods.