Qualitative and quantitative analyses of influenza virus receptors in trachea and lung tissues of humans, mice, chickens and ducks

To accurately determine the expression and distribution patterns of two influenza virus receptors (SA alpha 2,3-gal and SA alpha 2,6-gal) in trachea and lung tissues of humans, mice, chickens and ducks, we analyzed lectin immunofluorescence stainings of various tissue sections qualitatively and quantitatively. Results from the qualitative analysis showed that both influenza virus receptors were expressed in lung tissues of humans, mice, chickens and ducks as well as trachea tissues of mice and ducks. However, SA alpha 2,6-gal receptor was expressed only in the human trachea tissue and SA alpha 2,3-gal receptor was expressed only in the chicken trachea tissue. Results from the quantitative analysis demonstrated that both receptors were expressed in trachea tissues of human and mouse, as well as in lung tissues of humans, chickens and ducks. Meanwhile, our results also showed that the expression and distribution of influenza virus receptors in the same tissue were not always uniform, indicating that their distribution and expression in various tissues are not simply the distinction between the presence or absence of receptors, but rather the difference in the amount of expressed receptors.