Sensory neurons regulate immunoglobulin secretion of spleen cells: Cellular analysis of bidirectional communications between neurons and immune cells

The effects of primary sensory neurons in the dorsal root ganglia (DRG) on immunoglobulin (Ig)-secreting activity of spleen cells were investigated in culture. The conditioned medium (CM) of normal spleen cells stimulated DRG neurons to release neurokinin A which increased the number of Ig-secreting spleen cells. In contrast, the CM of concanavalin A-induced suppressor spleen cells induced the release of vasoactive intestinal peptide, an inhibitor of Ig secretion of spleen, from DRG neurons. These findings indicate that sensory neurons can help and suppress Ig secretion, and these bidirectional activities are controlled by the factors released from immune cells.