Interleukin-16 for the gene therapy of HIV infection

Interleukin 16 (IL-16) has been shown to function as chemoattractant factor, as a modulator of T-cell activation and as an inhibitor of human immunodeficiency virus (HIV) replication. It is now clear that IL-16 is synthesised as a large precursor molecule (pro-IL-16), from which as yet unidentified proteases release a bioactive carboxyterminal fragment. The mechanism for IL-16 secretion is still unknown, but it is likely that the secreted protein is smaller than the originally published 130 amino acids. Upon transfection of an IL-16 cDNA, human T-cells became virtually resistant against HIV infection. This system may well be helpful in studying the mechanism of HIV suppression by this lymphokine. In addition, this approach could potentially be important for the development of gene therapy against HIV.