Lectin-like attachment sites on murine pulmonary alveolar macrophages bind Aspergillus fumigatus conidia

Murine pulmonary alveolar macrophages bound Aspergillus fumigatus conidia in vitro at 4 C and 37 C in the absence of serum or opsonins. This attachment was dependent on calcium and was sensitive to mild trypsinization and paraformaldehyde pretreatment of the macrophage membrane. Chitotriose, N-acetylglucosamine, D-mannose, α-methyl-mannoside, and L-fucose, but not D-galactose, were effective inhibitors of conidial binding. This pattern of reduction of conidial binding was consistent with that for the mannosyl-fucosyl receptor. In addition, conidial binding may be mediated by another lectin on the macrophage membrane, one that recognizes chitin components, because N-acetylglucosamine and chitotriose exhibited greater inhibition than expected for the mannosyl-fucosyl lectin.