Fig. 7. T. gondii infection renders cells resistant to apoptosis. (A-E') MØs were serum-starved for 18 hours, infected with Toxoplasma; 2 hours later staurosporine (1 µM) was added to cell cultures. After 18 hours, cells were subjected to TUNEL-FITC (green) and anti-p30 (SAG-1) Alexa Fluor 594 (red) staining, nuclei were stained with DAPI (blue). (A) Non-infected cell showing DAPI-stained nucleus. (A') Same cell as in A, showing TUNEL- and nuclei-staining (green and blue, respectively, appearing as turquoise). (B-E) Cells from the same population. Examples of infected cells, showing parasite-staining (red) and lack of TUNEL-stained nuclei (therefore remaining blue). Arrows point to tachyzoites in an intracellular location. (F) Quantitation of TUNEL-staining-positive cells. Med, cultured in medium alone; STS, cells cultured with staurosporine; I/STS, infected cells subjected to STS treatment; NI/STS, non-infected cells cultured with STS. ^*P<0.05; 100 cells were counted in each sample. Bars, 5 µm. This experiment was performed three times with the same result.