FIG. 3.

Antibodies against CR1 (anti-CD35) block binding of HCV to erythrocytes. The erythrocytes (5 × 10⁸ cells total) in 2 mL of RPMI medium were mixed with 6 μg antibodies as stated and incubated at 25°C for 30 minutes. A mixture of complement opsonized HCV1a virus particles (pre-incubation at 25°C for 30 minutes, 1.5 × 10⁷ copies total) were added and incubated further at 25°C for 15 minutes. After adding EDTA to a final concentration of 20 mM, the erythrocytes were collected by centrifugation and washed three times with 1× PBS, pH7.4. Total RNA isolation from erythrocytes and quantification of HCV RNA were performed as described in the Methods section. Each value represents the mean ± standard deviation of six determinations. The data are representative of two independent experiments using erythrocytes from at least two different healthy donors. SC, Santa Cruz; BD, BD Biosciences.