Figure 4From: Nasal lavage natural killer cell function is suppressed in smokers after live attenuated influenza virusCharacterization of NK cells in the Nasal Lavage by Immunohistochemistry. NLF cells were characterized using immunohistochemistry. A) NLF cells are stained with anti-CD56-HRP to identify NK cells and B) NLF cells are stained with anti-perforin-HRP to identify cytotoxic NK cells. Bar = 10 μm.Back to article page