The role of CD4-dependent signaling in interleukin-16 induced c-Fos expression and facilitation of neurite outgrowth in cerebellar granule neurons.

Neuronal interleukin 16 (NIL-16) is the larger neural-specific splice variant of the interleukin-16 (IL16) gene and shows restricted expression to post-mitotic neurons of the mammalian hippocampus and cerebellum. Although the N-terminus of NIL-16 is unique to the neuronal variant, the C-terminus is identical to pro-IL-16, the IL-16 precursor expressed primarily in T-cells. IL-16 was originally described as a proinflammatory cytokine and has diverse immunoregulatory effects which involve signaling through CD4.