The neuropilins (NRPs) are single-pass multifunctional transmembrane glycoproteins that play an important role in cell development, immunity and cancer, and physiological and pathological angiogenesis. They were first discovered as regulators of nervous system development, acting as semaphorin co-receptors with plexins, as well as enhancers of cellular responses to members of the vascular endothelial growth factor (VEGF) family.

The NRP family comprises two members: Neuropilin-1 (NRP1) and Neuropilin-2 (NRP2), which are usually expressed as homodimers but can also appear as heterodimers. NRP2 contains a large extracellular N-terminal which consists of five domains, a short transmembrane domain and a small cytoplasmic domain^1-3. 

NRP2 is expressed in a wide variety of cells including endothelial cells, neurons, pancreatic islet cells, hepatocytes, melanocytes and osteoblasts. NRP2 has been shown to mediate proliferation, survival, and migration of tumor cells³.

NRP2 knockout mice studies show that mice are viable without defects in blood vessels but display abnormal lymphatic development and defects of the central and peripheral nervous systems².