In the battle to treat the pandemic of obesity, one therapeutic strategy is to block endogenous signals that stimulate appetite
and control body weight. One such molecule is ghrelin, a gut peptide that is the only known orexigenic hormone and is a likely
contributor to mealtime hunger. The relative importance of ghrelin in long-term body-weight regulation (and thus its promise
as an anti-obesity target) is uncertain, however, because genetic and pharmacologic blockade of ghrelin signaling have yielded
variable results to date. Using a novel approach of vaccinating rats against their own ghrelin, Zorilla et al. report that
animals with high ghrelin-specific antibody titers displayed restricted body weight, without evidence of non-specific inflammation
following the vaccine. These results favor a meaningful role for ghrelin in energy homeostasis, hinting at a possible new
anti-obesity approach. More broadly, the work of Zorilla et al. supports the feasibility of vaccinations directed against
specific autologous targets––immunopharmacotherapy that could potentially be developed to target a wide array of medical conditions.
