Leishmanial Excretory-Secretory proteins: A potent vaccine candidate

Leishmaniasis is caused by the intracellular parasite of the genus Leishmania. It now becomes a major public health problem in many countries all over the world. It is always better to prevent the disease than to treat it. The vaccine prevents disease in the people who receive them and protect those who come into contact with an unvaccinated individual. Because of the large genome and complex biology, developing a vaccine for this pathogen has proved to be a challenging task. Leishmania promastigotes are successfully cultivated incompletely defined medium and their excretory-secretory proteins/factors which may act as antigens are easily purified form culture supernatant of cultured Leishmania species. These leishmanial excretory-secretory antigens serve as a candidate for vaccine development in formulation with muramyl dipeptide (MDP) as an adjuvant. However, currently, there is not a single vaccine is available against any form of leishmaniasis for general human use. According to the estimate of the World Health Organization (WHO), 90% of visceral leishmaniasis (VL) occurs in just five countries (Bangladesh, Brazil, India, Nepal, and Sudan). Those in need are amongst the poorest people in these countries to develop a vaccine. The main purpose of this review is to present only the use of Leishmania excretory-secretory antigens (LESAs) as a candidate for the formulation of a potent vaccine against the severe disease leishmaniasis