The frequency of sandfly-host contacts can be measured by host antibody levels against sandfly salivary proteins. Recombinant salivary proteins are suggested to represent a valid replacement for salivary gland homogenate (SGH); however, it is necessary to prove that such antigens are recognized by antibodies against various populations of the same species. Phlebotomus perniciosus (Diptera: Psychodidae) is the main vector of Leishmania infantum (Trypanosomatida: Trypanosomatidae) in southwest Europe and is widespread from Portugal to Italy. In this study, sera were sampled from naturally exposed dogs from distant regions, including Campania (southern Italy), Umbria (central Italy) and the metropolitan Lisbon region (Portugal), where P. perniciosus is the unique or principal vector species. Sera were screened for anti-P. perniciosus antibodies using SGH and 43-kDa yellow-related recombinant protein (rSP03B). A robust correlation between antibodies recognizing SGH and rSP03B was detected in all regions, suggesting substantial antigenic cross-reactivity among different P. perniciosus populations. No significant differences in this relationship were detected between regions. Moreover, rSP03B and the native yellow-related protein were shown to share similar antigenic epitopes, as canine immunoglobulin G (IgG) binding to the native protein was inhibited by pre-incubation with the recombinant form. These findings suggest that rSP03B should be regarded as a universal marker of sandfly exposure throughout the geographical distribution of P. perniciosus.

Department of Biomedical and Medical Sciences University of Algarve Faro Portugal

Department of Parasitology Faculty of Science Charles University Prague Prague Czech Republic

Department of Veterinary Medicine and Animal Production University Federico 2 Naples Italy

Department of Veterinary Medicine University of Perugia Perugia Italy

Faculty of Veterinary Medicine Lusophone University of Humanities and Technologies Lisbon Portugal

Global Health and Tropical Medicine Medical Parasitology Unit Instituto de Higiene e Medicina Tropical New University of Lisbon Lisbon Portugal

Unit of Vector Borne Diseases and International Health Istituto Superiore di Sanità Rome Italy

Warwick Infectious Disease Epidemiology Research School of Life Sciences University of Warwick Coventry U K

References provided by Crossref.org

Assessment of the exposure to Phlebotomus perniciosus and the presence of anti-Leishmania infantum antibodies in stray cats in an endemic region of Spain, and their potential correlation with environmental factors

Exposure to Phlebotomus perniciosus sandfly vectors is positively associated with Toscana virus and Leishmania infantum infection in human blood donors in Murcia Region, southeast Spain

PpSP32-like protein as a marker of human exposure to Phlebotomus argentipes in Leishmania donovani foci in Bangladesh

Phlebotomus perniciosus Recombinant Salivary Proteins Polarize Murine Macrophages Toward the Anti-Inflammatory Phenotype

Monitoring Leishmania infection and exposure to Phlebotomus perniciosus using minimal and non-invasive canine samples

Exploring the relationship between susceptibility to canine leishmaniosis and anti-Phlebotomus perniciosus saliva antibodies in Ibizan hounds and dogs of other breeds in Mallorca, Spain

Field study of the improved rapid sand fly exposure test in areas endemic for canine leishmaniasis

Antibody response to Phlebotomus perniciosus saliva in cats naturally exposed to phlebotomine sand flies is positively associated with Leishmania infection

Synthetic peptides as a novel approach for detecting antibodies against sand fly saliva

Human antibody reaction against recombinant salivary proteins of Phlebotomus orientalis in Eastern Africa

Seasonal dynamics of canine antibody response to Phlebotomus perniciosus saliva in an endemic area of Leishmania infantum

Evaluation of the rSP03B sero-strip, a newly proposed rapid test for canine exposure to Phlebotomus perniciosus, vector of Leishmania infantum

Insights into the sand fly saliva: Blood-feeding and immune interactions between sand flies, hosts, and Leishmania