Humoral Responses and Ex Vivo IFN-γ Production after Canine Whole Blood Stimulation with <i>Leishmania infantum</i> Antigen or KMP11 Recombinant Protein

Abstract

The effect of Leishmania infantum soluble antigen (LSA) and recombinant Kinetoplastid Membrane Protein 11 (rKMP11) on the induction of ex vivo specific IFN-γ (n = 69) and antibody responses (n = 108) was determined in dogs. All dogs were tested for serological response to both antigens and divided into Group 1: healthy (Asturias, Spain, n = 26), Group 2: sick (n = 46), Group 3: healthy Ibizan hounds (Mallorca, Spain, n = 22) and Group 4: healthy (Bari, Italy, n = 14). Antibody levels were higher for LSA when compared to rKMP11 (p = 0.001). Ibizan hounds were all seronegative to rKMP11 and 18% were low seropositive to LSA. Sick dogs presented higher antibody response to both antigens compared to the rest of the groups (p p p < 0.05). IFN-γ to LSA and rKMP11 stimulation was observed in 34% and in 2.8% of the sick dogs, respectively. Here, we demonstrated that anti-rKMP11 antibodies are mainly present in dogs with moderate to severe disease. Furthermore, cellular immune response measured by specific ex vivo IFN-γ production was more intense to LSA than stimulated to rKMP11.

Keywords

• leishmaniosis
• serology
• dog
• cell-mediated immunity
• diagnosis