Probably involved in bacterial recognition and uptake by its host (human) (PubMed:25041568). Immunoelectron microscopy indicates this protein is displaced from the cell surface (PubMed:25041568). Fragments of the mature protein (residues 61-80, 101-120 and 121-140) prevent uptake of M.tuberculosis by a human macrophage-like cell line (PubMed:25041568).