May be involved in the regulation of the cytoskeleton through interaction with the subpellicular microtubules. May be involved in parasite mobility and attachment to the surface of the host cell. Strongly stimulates T-cell proliferation and is thought to play a role in the immunology of leishmaniasis. Monomer. Associated with microtubules. Present in both promastigotes and amastigotes. A minor in vivo processed fragment (IVP) also exists, probably as a result of proteolysis. Probably O-glycosylated. Contains equimolar amounts of galactosamine, galactose, glucose and mannose. The N-terminus is blocked. Belongs to the KMP-11 family.