Cross-protection among unrelated leptospira pathogens serovars: an unfinished story.

Background. The World Health Organization considers leptospirosis the most neglected zoonotic disease in the last decades. One of the major obstacles in the developing of vaccines for the prevention of leptospirosis is the absence of cross-protection among unrelated serovars. It is accepted that cross-protection among related serovars is due to antibodies generated against lipopolysaccharides (LPs), whereas a cross-protection among unrelated serovars is rarely observed. Objectives. The objective of the study was to ascertain the existence of cross-protection among vaccine strains of different serovars. Results. The results of this research demonstrated that a cross-protection among unrelated Leptospira serovars strain is possible. The Canicola strain is able to induce protection against homologous, Ballum and Copenhageni strains. The Mozdok strain induced protection only against a homologous challenge. Other strains showed a moderate cross-protection against a heterologous challenge. Conclusions. These findings suggest that the Canicola and Mozdok strains are ideal candidates for developing a new vaccine formulation for use in Cuba (Adv Clin Exp Med 2012, 21, 5, 581–589).