Midbrain dopamine drives splenic immunity through a brain-to-body circuit.

Midbrain dopamine neurons are well-known to shape central nervous system function, yet there is growing evidence for their influence on the peripheral immune systems. Here we demonstrate that midbrain dopamine neurons form a circuit to the spleen via a multisynaptic pathway from the dorsal vagal complex (DVC) through the celiac ganglion. Midbrain dopamine neurons modulate the activity of D1-like and D2-like dopamine receptor-expressing DVC neurons.