Fig. 9

Bluetongue virus infection can be studied in several organs of the same Culicoides sonorensis. Salivary apparatus, gut and ovaries of the same C. sonorensis female at 8 days post oral infection with BTV. Images on the left show one plane taken with differential interference contrast (DIC) microscopy and show cell nuclei in blue (DAPI staining). Images on the right are immunofluorescence (IF) maximum projections of at least 50 stacked plane images, where cell nuclei are shown in blue (DAPI staining), cellular tubulin is visualised in red (labelling with mouse anti-tubulin, and anti-mouse IgG AlexaFluor™ 568) and BTV structural proteins (VSPs) are visualized in green (labelling with in-house antibody Orab279 and anti-guinea pig IgG AlexaFluor™ 488). In the salivary apparatus, BTV infection can be observed in the accessory glands, but not in the main salivary gland. In the gut, MT show the Malpighian tubules, HG show the hind gut, and MG show the midgut. The latter is infected by BTV. In the ovaries, ovarioles can be observed, which contain egg cells or oocytes (O) and nurse cells (N). BTV was detected outside the ovarioles, but not within. In all panels microscope magnification is shown on the top right corner and the scale bar represents 20 µm