Figure 4. Effect of A. castellanii trophozoites on secretion of IL-8 by HEK-293 cells.

HEK-293 cells expressing only TLR3 or TLR4 were cultured with A. castellanii trophozoites (1×10⁵ cells/ml). As a positive control, HEK-293 cells were activated with 125 ng/ml poly (I:C) (A specific ligand for TLR3) and 100 ng/ml ultrapure LPS (A specific ligand for TLR4/MD2) for 24 hours. Supernatants were collected from harvested cells and subjected to IL-8 specific ELISA. The data are mean±SEM of three independent experiments. Asterisk indicates P value < 0.05 by unpaired Student’s t-test.