Fourth, although a vasoactive peptide (maxadilan) from the L. longipalpis saliva is shown to indeed increased production of prostaglandin E2 (PGE2) (62) and reciprocally modulate TNF-α and IL-6 production from BALB/c macrophages in a PGE2-dependent manner (62), the regulation of IL-27 by maxadilan and a correlation between PGE2 and IL-27 in experimental Leishmaniasis require further investigation. The gene discussed is IL27; the disease is leishmaniasis.