Fig. 4
From: Immune-suppression by OsHV-1 viral infection causes fatal bacteraemia in Pacific oysters
Accumulation of bacteria in tissues of the susceptible SF11 oysters. Giemsa staining was performed on paraffin wax-embedded tissue histological sections of SF11 oysters sampled at different time points to visualize tissue colonization by bacteria. Oyster tissues and cells were coloured in shades of pink to purple, and most bacteria appeared in deep blue (scale bars corresponds to 20 µM). a At 54 h after the beginning of the ‘natural’ experimental infection, bacteria accumulated in the gills of the SF11 oysters (filled arrowheads). Rounded cells reminiscent of haemocytes were found in both gill tissues and outside tissues in the vicinity of the bacteria (open arrowheads). At 78 h, gill tissues appeared massively degraded, and bacteria were found in most tissues of the SF11 oysters, e.g., in b gills, c adductor muscle and d interstitial tissues near the digestive tract. No bacteria or tissue damage were observed on sections of SF11 or RF21 either at the beginning of the experimental infection or at any time points for the RF21 oyster sections (Supplementary Fig. 8)
