Ganglioside GM1 asialo is a component of cellular lipid rafts and can be formed by the cleavage of the sialic acid residue from ganglioside GM1 by neuraminidase. Ganglioside GM1 asialo is a glycolipid receptor for P. aeruginosa flagellin and stimulates defensive responses in host cells, including extracellular ATP release, calcium mobilization, and ERK1/2 phosphorylation when stimulated by flagellin and an anti-ganglioside GM1 asialo antibody. The percentage of ganglioside GM1 asialo-positive natural killer (NK) and CD8+ T cells in lung is increased in a mouse model of respiratory syncytial virus (RSV) infection compared with healthy animals. Depletion of ganglioside GM1 asialo-positive NK and T cells reduces IFN-γ levels in the lung, reduces weight loss, and increases lung viral load in RSV-infected mice. Ganglioside GM1 asialo mixture contains ganglioside GM1 asialo molecular species with C18:1 and C20:1 sphingoid backbones.