Figure 5.

The HBcAg can induce B7.2 and B7.1 mRNA in unprimed B cells. Unprimed, splenic B cells derived from B10.S mice were cultured in media alone (M), with 3 concentrations of LPS-free, yeast-derived rHBcAg (kindly provided by P. Valenzuela, Chiron, Emeryville, CA) (10, 5, and 2 μg/ml), with P16 (10 μg/ml), or LPS (10 μg/ml). After 48 h and 72 h of culture, the B cells were harvested and the presence of B7.2 mRNA (A) and B7.1 mRNA (B) was determined by RT-PCR. The expected sizes of the amplified products were 496 bp for B7.1, 404 bp for B7.2, and 245 bp for β-actin. A 100-bp ladder was used as a DNA size marker.