Effects of specific antisera targeting peritrophic matrix-associated proteins in the sand fly vector Phlebotomus papatasi

Abstract

In many hematophagous insects, the peritrophic matrix (PM) is formed soon after a blood meal (PBM) to compartmentalize the food bolus. The PM is an important component of vector competence, functioning as a barrier to the development of many pathogens including parasites of the genus Leishmania transmitted by sand flies. PM morphology and permeability are associated with the proteins that are part of the PM scaffolding, including several peritrophins, and chitin fibers. Here, we assessed the effects of specific antisera targeting proteins thought to be an integral part of the PM scaffolding and its process of maturation and degradation. Phlebotomus papatasi sand flies were fed with red blood cells reconstituted with antisera targeting the chitinase PpChit1, and the peritrophin PpPer2. Sand fly midguts were dissected at different time points and processed for light microscopy (LM), confocal and transmission electron (TEM) microscopies (24, 42-46, 48 and 72h PBM), scanning electron (SEM) (48h PBM) and atomic force (AFM) (30h PBM) microscopies. TEM and WGA-FITC staining indicate PM degradation was significantly delayed following feeding of flies on anti-PpChit1. AFM analysis at 30h PBM point to an increase in roughness' amplitude of the PM of flies that fed on either anti-PpChit1 or anti-PpPer2. Collective, our data suggest that antibodies targeting PM-associated proteins affects the kinetics of PM maturation, delaying its degradation and disruption and are potential targets on transmission-blocking vaccines strategies.

Asaia symbionts interfere with infection by Flavescence dorée phytoplasma in leafhoppers

“…Key to the transmission process are the digestive tract and the salivary glands of the insect. In the midgut, interactions with the peritrophic matrix and gut epithelia have been found to be crucial for microbial invasion of the insect's hemocoel (Killiny et al 2005;Lo et al 2013;Rashidi et al 2015;Buchon et al 2016;Malta et al 2016).…”

Identification and characterization of two novel peritrophic membrane (PM) genes in the Chinese mitten crab Eriocheir sinensis that exhibit activity against high-pH stress and Aeromonas hydrophila challenge

“…Several peritrophins, including IIMs (McIIM1, McIIM2 and McIIM4), nonmucin peritrophins (McPM1 and McPPAD1), chitin deacetylase (McCDA1) and others, have already been characterized (Toprak et al, ). Previous studies have indicated that peritrophins contribute to the maintenance of structural characteristics, including strength, elasticity and permeability, and to some extent, affect the biological functions of the PM via disulphide bonds, O‐linked glycosylations or multiple CBDs (Malta et al, ; Venancio, Cristofoletti, Ferreira, Verjovskialmeida, & Terra, ).…”

“…Several (Toprak et al, 2016). Previous studies have indicated that peritrophins contribute to the maintenance of structural characteristics, including strength, elasticity and permeability, and to some extent, affect the biological functions of the PM via disulphide bonds, O-linked glycosylations or multiple CBDs (Malta et al, 2016;Venancio, Cristofoletti, Ferreira, Verjovskialmeida, & Terra, 2009). The PM has also been observed in crustaceans.…”

Characteristics of the Peritrophic Matrix of the Silkworm, Bombyx mori and Factors Influencing Its Formation

“…Several studies have suggested that antibodies specific to PM proteins impede insect development by binding their target antigens in the PM and blocking PM pores. In turn, nutrient uptake and/or the passage of digestive enzymes between the endoand ectoperitrophic spaces were inhibited [16][17][18]. When the transcript levels of chitinase are reduced in the larval midgut of Ostrinia nubilalis by feeding-based RNAi, the chitin content in the PM is significantly increased; however, larval body weight is significantly decreased compared with that of control larvae fed a diet containing GFP dsRNA [19].…”