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

Abstract

BackgroundHosts repeatedly bitten by sand flies develop antibodies against sand fly saliva and screening of these immunoglobulins can be employed to estimate the risk of Leishmania transmission, to indicate the feeding preferences of sand flies, or to evaluate the effectiveness of vector control campaigns. Previously, antibodies to sand fly saliva were detected using whole salivary gland homogenate (SGH) or recombinant proteins, both of which also have their disadvantages. This is the first study on sand flies where short peptides designed based on salivary antigens were successfully utilized for antibody screening.Methodology/Principal findingsSpecific IgG was studied in hosts naturally exposed to Phlebotomus orientalis, the main vector of Leishmania donovani in East Africa. Four peptides were designed by the commercial program EpiQuest-B, based on the sequences of the two most promising salivary antigens, yellow-related protein and ParSP25-like protein. Short amino acid peptides were synthesised and modified for ELISA experiments. Specific anti-P. orientalis IgG was detected in sera of dogs, goats, and sheep from Ethiopia. The peptide OR24 P2 was shown to be suitable for antibody screening; it correlated positively with SGH and its specificity and sensitivity were comparable or even better than that of previously published recombinant proteins.Conclusions/SignificanceOR24 P2, the peptide based on salivary antigen of P. orientalis, was shown to be a valuable tool for antibody screening of domestic animals naturally exposed to P. orientalis. We suggest the application of this promising methodology using species-specific short peptides to other sand fly-host combinations.

A synthetic peptide analog of in silico‐predicted immunogenic epitope unique to dengue virus serotype 2 NS1 antigen specifically binds immunoglobulin G antibodies raised in rabbits

“…We hypothesized and proved in vivo that this antigenic epitope would be able to specifically capture specific antipeptide antibodies similar to previous studies done by Roehrig et al in 1989 for Murray Valley, Williams et al for human immunodeficiency virus in 2016, Lee et al for Zika in 2017, Navarro et al for Escherichia coli in 2016, and recently by Sima et al for Phlebotomus orientalis in 2018. The studies mentioned were capable of determining infections by detecting antipeptide antibodies with up to 100% sensitivity and 100% specificity …”

ELIPSE-COL: A novel ELISA test based on rational envisioned synthetic peptides for detection of SARS-CoV-2 infection in Colombia

“…Peptides can be synthesized in large quantities with very high purity and without recombinant cellular expression systems, and those who specifically bind to target antibodies are valuable ligands useful in serological assays (10, 11). Relative chemical stability of short peptides and the relative ease with which they can be synthesized and manipulated (12, 13).…”