Camila Freitas Poster 2025

Dr Camila Freitas

Federal University of Minas Gerais, Brazil

Immunization with Recombinant LiHyp1 Protein Plus Adjuvant Provides Protection Against Tegumentary Leishmaniasis in a murine model

Poster Abstract

Tegumentary leishmaniasis (TL) is a neglected tropical disease caused by protozoa of the genus Leishmania, resulting in significant morbidity and social impact in endemic regions. Current treatment options are often toxic, expensive, and limited in efficacy, highlighting the urgent need for effective vaccines to prevent infection. In this study, we evaluated the immunogenicity and protective potential of the recombinant LiHyp1 protein formulated with a Th1-type adjuvant against TL caused by Leishmania (L.) amazonensis.

The recombinant LiHyp1 protein was produced using bacterial expression systems, purified, and combined rLiHyp1 plus saponin (rLiHyp1/S) or incorporated in micelles (rLiHyp1/M) as adjuvants. BALB/c mice were immunized subcutaneously and subsequently challenged with L. amazonensis promastigotes. The immune response was analyzed by measuring cytokine production (IFN-γ, TNF-α, IL-12, IL-4 and IL-10) and specific antibody titers, while parasite load reduction was assessed in infected tissue.

Immunization with LiHyp1 plus adjuvant induced a robust Th1-type immune response characterized by elevated levels of IFN-γ, IL-12 and TNF-α, alongside a significant reduction in IL-10 and IL-4 levels. Antibody analysis revealed high titers of specific IgG2a, indicative of a strong cell-mediated immunity. Vaccinated mice receiving rLiHyp1/S or rLiHyp1/M showed a significant reduction in lesion size and parasite load compared to controls, demonstrating the protective efficacy of the vaccine formulation.

These findings highlight the potential of LiHyp1 protein as a vaccine candidate for TL and support its further development as part of integrated control strategies for leishmaniasis. This study contributes to the growing body of evidence supporting recombinant proteins as viable components in vaccines against neglected tropical diseases.

Biography

Dr. Camila Simões de Freitas is a Postdoctoral Researcher at the Federal University of Minas Gerais (UFMG), Brazil, with a PhD in Infectious Diseases and Tropical Medicine. Her research focuses on vaccine development, diagnostics, and therapeutics for neglected tropical diseases, particularly leishmaniasis. Her expertise includes cell culture, in vitro and in vivo infections, molecular biology, and immunological assays, essential for understanding host-pathogen interactions and novel control strategies. With international research experience, she is committed to translational science and strengthening vaccine and diagnostic R&D in low-resource settings.