A vaccine composed of a hypothetical protein and the eukaryotic initiation factor 5a from Leishmania braziliensis cross-protection against Leishmania amazonensis infection

作者：Duarte Mariana Costa; Lage Daniela Pagliara; Martins Vivian Tamietti; Costa Lourena Emanuele; Ravena Severino Carvalho Ana Maria; Ludolf Fernanda; de Oliveira Santos Thais Teodoro; Vale Danniele Luciana; Roatt Bruno Mendes; Menezes Souza Daniel; Fernandes Ana Paula; Pereira Tavares Carlos Alberto; Ferraz Coelho Eduardo Antonio

来源：Immunobiology, 2017, 222(2): 251-260.

DOI：10.1016/j.imbio.2016.09.015

• Hypothetical proteins
• Eukaryotic initiation factor 5a
• Cross-protection
• Vaccine
• Tegumentary leishmaniasis
• Th1 immunity

In the present study, two proteins cloned from Leishmania braziliensis species, a hypothetical protein (LbHyp) and the eukaryotic initiation factor 5a (EiF5a), were evaluated to protect BALB/c mice against L. amazonensis infection. The animals were immunized with the antigens, either separately or in combination, using saponin as an immune adjuvant in both cases. Spleen cells from vaccinated and later infected mice produced significantly higher levels of protein and parasite-specific IFN-gamma, IL-12, and GM-CSF, in addition to low levels of IL-4 and IL-10. Evaluating the parasite load by means of a limiting dilution technique and quantitative Real-Time PCR, vaccinated animals presented significant reductions in the parasite load in both infected tissues and organs, as well as lower footpad swelling, when compared to the control (saline and saponin) groups. The best results regarding the protection of the animals were achieved when the combined vaccine was administered into the animals. Protection was associated with an IFN-gamma production against parasite antigens, which was mediated by both CD4(+) and CD8(+) T cells and correlated with antileishmanial nitrite production. In conclusion, data from the present study show that this polyprotein vaccine, which combines two L braziliensis proteins, can induce protection against L. amazonensis infection.

• 出版日期2017-2