Polymerase chain reaction-based assay for the detection and identification of sand fly gregarines in Lutzomyia longipalpis, vector of visceral leishmaniasis

Abstract

Gregarines that parasitise phlebotomine sand flies belong to the genus Psychodiella and, even though they are highly host-specific, only five species have been described to date. Their most outstanding features include the unique localisation of the oocysts in the accessory glands of the female host, which ensures contamination of the egg surface during oviposition, and the fact that they naturally parasitise the vectors of Leishmania, causal agent of leishmaniasis. The type species, Ps. chagasi, was first described in Lutzomyia longipalpis, vector of visceral leishmaniasis (VL), from Brazil. We recently reported Ps. chagasi sequences in Lu. longipalpis from Posadas (Misiones, Argentina), an endemic VL location where this gregarine had not been previously recorded. In order to analyse the incidence of Ps. chagasi infections in Lu. longipalpis from this location, the aim of this study was to develop a diagnostic assay for sand fly gregarine parasites in Lu. longipalpis. For this, we designed primers using the Ps. chagasi sequences we previously identified and performed an in vitro validation by PCR amplification of the original sand fly samples. Their specificity and sensitivity as diagnostic primers were subsequently confirmed by PCR reactions using total DNA extracted from naturally infected Lu. longipalpis from the same location (Posadas, Argentina).Fil: Caligiuri, Lorena Gisel. Universidad Nacional de La Plata. Centro Regional de Estudios Genómicos; Argentina. Universidad Nacional del Noroeste de la Provincia de Buenos Aires; ArgentinaFil: Acardi, Soraya Alejandra. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales. Laboratorio de Biología Molecular Aplicada; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Santini, Maria Soledad. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Centro Nacional de Diagnóstico e Investigaciones Endemo-epidémicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Salomón, Oscar Daniel. Ministerio de Salud. Instituto Nacional de Medicina Tropical; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mccarthy, Cristina Beryl. Universidad Nacional de La Plata. Centro Regional de Estudios Genómicos; Argentina. Universidad Nacional del Noroeste de la Provincia de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin