ABSTRACT
The Leishmanin Skin Test (LST) is performed via intradermal injection of Leishnnmia antigens to induce and visualize the adaptive immune response in individuals who have been previously infected with Leishmania. This chapter presents the history of the LST and call for developing a standardized leishmanin that is produced under Good Manufacturing Practice conditions and obtains the World Health Organization diagnostic prequalification for use in endemic countries. While leishmanin was originally made of killed whole promastigotes, it has since been reported that soluble Leishmania antigen is more sensitive and potent. The preparation of soluble leishmanin involves the disruption of parasites, and it has been suggested that this process causes immunogenic epitopes to be more available for uptake by antigen-presenting cells, resulting in the increased sensitivity. The development of a vaccine would advance the elimination of Visceral leishmaniasis from the Indian subcontinent and Africa as well as help prevent all forms of leishmaniasis worldwide.
