FIG. 9.

Kinetics of intracellular TNF-α expression by splenic macrophages from PEG IFN-α-treated and untreated BALB/c mice given a subcutaneous challenge with virulent VEEV. Mice were given 100 μl i.p. of either 4 × 10⁴ U of PEG IFN-α in 1% NMS in N-saline (□) or just 1% NMS in N-saline (■) on days −2 to +5 after infection with ca. 25 MLD (25 PFU) of VEEV in 100 μl of L-15 MM on day 0 p.i. The data represent the fraction of splenic CD11b⁺ cells expressing intracellular TNF-α following 4 h of culture at 37°C with Golgistop and VEEV E2 antigen. Results shown are the mean + 95% confidence limits of five mice per time point.