Immune semaphorins: novel features of neural guidance molecules

The immune and nervous system have various common features in the functional characteristics. Both have an intricate network of synaptic connections and an exquisite communication system that enables intercellular signal transduction. They also share a number of messenger molecules such as cytokines and chemical mediators.

Semaphorins, well-defined axonal guidance molecules in the nervous system, also play critical roles in immune regulation. Various types of semaphorins, including secreted, transmembrane, truncated, and glycosylphosphatidylinositol-anchored forms, function during immune responses. However, some semaphorins utilize receptors in the immune system that are distinct from receptors in the nervous system.

This review presents a current overview of 'immune semaphorins' and their receptors, providing insight into the pleiotropic activity of this protein family.