FIG. 4.

Increased IL-8 mRNA expression after T. gondii infection of HeLa cells. Monolayers of HeLa cells in 25-cm² tissue culture flasks were infected with 5 × 10⁵ T. gondii tachyzoites and incubated for the indicated periods. Total RNA was extracted, and levels of IL-8 and β-actin transcripts were determined by RT-PCR. Twenty microliters of each PCR mixture was electrophoresed and stained with ethidium bromide. As a negative control, RNA was omitted from reverse transcription and PCR amplification (No RNA).