Effective immuno-therapeutic treatment of Canine Leishmaniasis

PLoS Negl Trop Dis. 2023 May 22;17(5):e0011360. doi: 10.1371/journal.pntd.0011360. eCollection 2023 May.

Abstract

Background: Canine Leishmaniasis (CanL) caused by the L. infantum species is one of the biggest threats to the health of the South American canine population. Chemotherapeutics currently used for the treatment of CanL fail to induce a total parasite clearance while inducing numerous side effects. As CanL is an immunomodulated disease, the use of immuno-treatments should strengthen the deficient immune response of infected dogs. In this study, we evaluated a nasally administered immunotherapy in dogs naturally infected with L. infantum (stage 2), with both visceral and cutaneous manifestations. Noteworthy, some of them were also infected by other parasites (E. canis, D. immitis, A. platys), what worsen their chance of survival.

Methodology/principal findings: The treatment was based on 2 intranasal (IN.) administrations of a killed L. infantum parasite loaded into maltodextrin nanoparticles, which treatment was compared with the classical oral administration of Miltefosine (2 mg/kg) for 28 days, as well as a combination of these 2 treatments. The results showed that two IN administrations significantly reduced the serology, and were at least as efficient as the chemotherapy to reduce the skin and bone marrow parasite burden, as well as clinical scores, and that unlike Miltefosine treatments, this nasally administered nanoparticle vaccine was without side effects.

Conclusions: These results confirm the feasibility of a simple therapeutic immuno-treatment against L. infantum infected dogs, which is a promising tool for future developments.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dog Diseases* / drug therapy
  • Dogs
  • Leishmania infantum*
  • Leishmaniasis* / drug therapy
  • Leishmaniasis* / veterinary
  • Leishmaniasis, Visceral* / drug therapy
  • Leishmaniasis, Visceral* / veterinary

Substances

  • miltefosine

Grants and funding

The study was founded by the company Vaxinano, and FF, AS and DB are employees at Vaxinano. AG is consultant for Vaxinano. Vaxinano played a role in the study design, the data analysis and the decision to publish.