Interleukin-16 and peptide derivatives as immunomodulatory therapy in allergic lung disease.

The therapeutic potential of interleukin (IL)-16 and derived peptides in allergic asthma is considered, focusing on key interactions with CD4 and associated chemokine receptors. IL-16 is a pleiotropic cytokine that has multiple effector functions with putative roles in varied T cell-mediated inflammatory diseases, such as asthma, inflammatory bowel disease and atopic dermatitis. Both in vitro and in vivo, IL-16 downregulates antigen-driven T cell activation, T helper 2 cytokine production and allergic airway inflammation. Peptides derived from the C-terminal bioactive portion of IL-16 offer advantages related to their retained immunomodulatory properties and absence of signalling in and chemoattraction to T cells.