FIG. 3.

Usage of CD163 variants to deplete a goat polyclonal antibody able to block PRRSV infection in macrophages. (a) The goat PAb AF1607 (R&D Systems) was passaged 16 times on transfected cells expressing different CD163 variants. Depletion of specific antibodies was confirmed via an immunofluorescence staining. Images represent an overlay of several z-sections throughout whole cells. Bar, 50 μm. (b) Depleted antibodies were used to treat macrophages for 1 h at 37°C prior to and during inoculation with PRRSV. Ten hours postinoculation, cells were fixed and infected cells were visualized using MAb P3/27 (32). The relative percentage of infected cells was calculated, with untreated cells as a reference. The average numbers of infected cells counted for each condition were 63 (mock), 30 (no depletion), 27 (depletion on K), 58 (depletion on B), 52 (depletion on S), and 35 (depletion on Q), respectively. Each value represents the mean ± standard deviation for three experiments. Different lowercase letters indicate statistically significant differences between treatments (one-way analysis of variance; Tukey B test, α < 0.05).