This gene encodes a protein that plays an important role in the innate immune response and is expressed in monocyte/macrophage cells. This gene product acts as a co-receptor that binds several microbial and fungal molecules, including lipopolysaccharides (LPS). This proteins LPS-binding activity is enhanced by the LPS binding protein (LBP) to allow binding to the TLR4-MD-2 co-receptor complex. The product of this gene is found in two forms, either as a soluble protein or attached to the cell surface by a glycosylphosphatidylinositol anchor.
