Fig. 7

TgCtwh6 tachyzoites upregulate APP, BACE1 and Aβ expression in HT22. After TgCtwh6 tachyzoites had been infected HT22 for 24 h, the HT22 were lysed and proteins were extracted. The expression of BACE1 and APP proteins was measured by western blotting and then analyzed with semiquantitative method (A–C). Moreover, RNA in the infected HT22 was extracted and reversely transcribed to cDNA. The expressions of BACE1 and APP genes was assessed by qRT-PCR and then semiquantitatively evaluated (D, E). Furthermore, after the HT22 cells had been fixed and the cytomembranes penetrated by Triton, the BACE1 and Aβ proteins were visualized in situ by immunofluorescence staining and observed under a fluorescence microscope at a magnification of 40 × 100 (scale bars, 50 μm). The percentage of positively stained cells was calculated using morphometric software (F–G). Data were represented as mean ± SEM and were analyzed by two-tailed Student’s t-test for comparing the difference between the two groups (n = 3 each group). *P < 0. 05, **P < 0.01, ***P < 0.001