Fig. 6

LACV infection induces syncytium-like aggregation and bystander cell death. Cultures described in Fig. 5 were stained for DAPI (blue), LACV (green), and active caspase-3 (red) and imaged using a × 40 objective. Weanling OB BCECs (a–d), adult OB BCECs (e–h) were mock-infected (a, e) or infected with LACV at MOIs of 0.1 (b, f), 1 (c, g), and 10 (d, h). Weanling cortical BCECs (i–l) and adult cortical BCECs (m–p) were mock-infected (i, m) or infected with LACV at MOIs of 0.1 (j, n), 1 (k, o), and 10 (l, p). Large, syncytium-like aggregation is noted as arrows in d and k). Combined counts of images from the OB and cortex samples at 10 MOI inoculum doses of LACV and active caspase-3-stained samples demonstrated an average of 2.3 ± 0.7 of cellular loss were counted per image of 10 representative images from weanling BCECs. In adults, 0.9 ± 0.3 foci of cellular loss were observed per image from10 representative images. 0.6 ± 0.2 syncytia were observed in a total of 11 images from weanling BCECs. In adults, 0.36 ± 0.28 syncytia were counted per image from 11 representative images. All images were at 10 MOI of inoculation dose. Scale bar = 20 μm