FIG. 3.

Library-derived A5 and A9a proteins do not use FeLV-A or FeLV-C receptors. Interference assays were used to examine receptor usage. lacZ transduction mediated by A5 or A9a on either AH927 (AH) or 293T cells infected with FeLV-A (A) and/or FeLV-C (C) was examined and compared with titers obtained on uninfected cells. The titer on infected cells as a percentage of that on uninfected is given in parentheses. Titers are TELCeB6 lacZ CFU per ml. Assays with 293T cells and AH927 cells were performed on different days and are each representative of two separate experiments.