Leica hi1210

Lung specimens were fixed with 10% neutral buffered formalin (NBF) for 24 hours and processed as described previously [40 (link)]. Lungs were embedded in paraffin wax using an embedding center (Leica EG1160, Leica Biosystems. Germany), sectioned using a microtome (Leica RM2135, Leica Biosystems. Germany) and fixed onto glass slides using a water bath (Leica HI1210, Leica Biosystems. Germany). Tissue sections were stained with Hematoxylin and Eosin (H&E) stain and mounted with diphenyl xylene (DPX) to be visualized using an upright light microscope (Eclipse LV150L, Nikon Instruments Inc., Japan). The examination was carried out as described previously [39 (link)]. Lung pathology was assigned microscopically one of four scores according to the severity of inflammation as follows: (1) normal histology; (2) mild focal inflammation; (3) moderate to severe focal inflammation with areas of normal tissue; and (4) severe inflammation to necrosis [38 (link)]. Lung cellular alterations were classified as acute or chronic inflammation [38 (link), 39 (link)].

Upon sacrifice, the thoracic cavity was opened by an excision through the peritoneum that was extended through the sternum and the rib cage was fully opened followed by the collection of liver and kidneys. The collected organs were fixed with 10% neutral buffered formalin (NBF) for 24 hours and then sliced into smaller pieces to be fixed again with NBF for another 24 hours. Histopathology examination was performed as described previously [28 (link)]. Briefly, fixed tissues were embedded in paraffin wax using an embedding center (Leica EG1160, Leica Biosystems), sectioned using a microtome (Leica RM2135, Leica Biosystems), and fixed onto glass slides using a water bath (Leica HI1210, Leica Biosystems). The paraffin sections were then stained with hematoxylin and eosin (H&E) stain mounted with diphenyl xylene (DPX) and visualized using an upright light microscope (Eclipse LV150L, Nikon).