LGALS9 and infection: It was found that the host GAL-3 and GAL-9 can attach to the parasite and cause it to bind to macrophages by detecting and binding to the β-galactosyl epitope on the lipopolysaccharide on the surface of Leishmania, potentially assisting the parasite in invading the body and causing infection (Pelletier et al., 2003; Turner et al., 2008).