SIGLEC5 is a member of the sialic acid-binding immunoglobulin-like lectin (Siglec) family. These cell surface lectins are characterized by structural motifs in the immunoglobulin (Ig)-like domains and sialic acid recognition sites in the first Ig V set domain. The encoded protein is a member of the CD33-related subset of Siglecs and inhibits the activation of several cell types including monocytes, macrophages and neutrophils. Binding of group B Streptococcus (GBS) to the encoded protein plays a role in GBS immune evasion.