Understanding Lung Deposition of Alpha-1 Antitrypsin in Acute Experimental Mouse Lung Injury Model Using Fluorescence Microscopy

Figure 3

Localization of rAAT-Alexa488 in the lung following single IT administration of 5 mg/kg rAAT-Alexa488 to ALI-induced mice. Immunofluorescence microscopy, showing rAAT-Alexa488 (green), acetyl-α-tubulin (red; (c) only), and cell nuclei labeled with DAPI (blue). rAAT-Alexa488 is primarily centered around large airways (a). Higher magnification shows that rAAT-Alexa488 is primarily distributed to the surface of pneumocytes (white arrowheads) lining alveoli and to interstitial spaces (yellow arrows) within lung parenchyma (b). The presence of rAAT-Alexa488 on the mucosal surface of large airways is confirmed by dual immunofluorescence with acetyl-α-tubulin, which is expressed by ciliated respiratory epithelial cells (orange fluorescence, yellow arrows) (c).

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(b)

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