Epitopes rationally selected through computational analyses induce T‐cell proliferation in mice and are recognized by serum from individuals infected with Schistosoma mansoni

Abstract

Schistosomiasis is the second leading cause of death due to parasitic diseases in the world. Seeking an alternative for the control of disease, the World Health Organization funded the genome sequencing of the major species related to schistosomiasis to identify potential vaccines and therapeutic targets. Therefore, the aim of this work was to select T and B-cell epitopes from Schistosoma mansoni through computational analyses and evaluate the immunological potential of epitopes in vitro. Extracellular regions of membrane proteins from the Schistosoma mansoni were used to predict promiscuous epitopes with affinity to different human Major Histocompatibility Class II (MHCII) molecules by bioinformatics analysis. The three-dimensional structure of selected epitopes was constructed and used in molecular docking to verify the interaction with murine MHCII H2-IA . In this process, four epitopes were selected and synthesized to assess their ability to stimulate proliferation of CD4 T lymphocytes in mice splenocyte cultures. The results showed that Sm041370 and Sm168240 epitopes induced significant cell proliferation. Additionally, the four epitopes were used as antigens in the Indirect Enzyme-Linked Immunosorbent Assay (ELISA) to assess the recognition by serum from individuals infected with Schistosoma mansoni. Sm140560, Sm168240, and Sm041370 epitopes were recognized by infected individuals IgG antibodies. Therefore, Sm041370 and Sm168240 epitopes that stood out in in silico and in vitro analyses could be promising antigens in schistosomiasis vaccine development or diagnostic kits. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:804-814, 2017.

Diagnostic performances of Schistosoma haematobium and Schistosoma mansoni recombinant proteins, peptides and chimeric proteins antibody based tests. Systematic scoping review

“…Furthermore, in silico discovery of immunoreactive B cell epitopes may allow the design of species-specific epitopes for serological diagnosis. Moreover, the possibility of construction of multi-epitopic chimeric proteins could improve the diagnostic accuracy of synthetic peptides [ 37 , 70 ].…”

“…In the present review, we identified two studies [ 16 , 37 ] that investigated peptide based serum IgG ELISA and one study [ 36 ] that utilized a multi-peptide chimeric protein. Except for Smp_167240 (213–228), Smp_141860 (1694–1709), Smp_141860 (1694–1706) and Sm 156860 which had poor diagnostic performances most peptides identified in this review had good diagnostic performances with sensitivities ranging from 67.71% to 96.15%, specificities ranging from 69.23% to 100% and AUC ranging from 0.76 (95% CI 0.6024–0.9213) to 0.99 (95% CI 0.987–100) ( Table 4 ).…”

Identification ofSchistosoma haematobiumandSchistosoma mansonilinear B-cell epitopes with diagnostic potential usingin silicoimmunoinformatic tools and peptide microarray technology

“…Carvalho and colleagues, 2022 and Lopes and colleagues, 2017 had previously used immunoinformatic approaches and immune-assay validation to identify S. haematobium and S. mansoni peptides with diagnostic potential (18,19). This study identified one peptide (AA81008-19-30) that had an excellent diagnostic performance for discriminating S. mansoni positives from healthy controls for IgG.…”

“…Eighteen previously published peptides were included on the peptide microarray, 10 from our previous study Vengesai and colleagues, 2022 (26) and 8 peptides from two studies by Carvalho and Colleagues, 2022 and Lopes and Colleagues, 2017 (18,19). Despite Carvalho and Colleagues, 2022 and Lopes and Colleagues, 2017 showing that peptides Sm168240, Smp_136560 (1564–1578), Smp_126160(438–452), Sm140560, Sm041370, Smp_180240(339–353), Smp_150390.1(216–230), Smp_093840(219–233) had AUC values ranging from 0.76 (95 % CI 0.6024-0.9213) to 0.99 (95 % CI 0.987-100) results from this current study show that only one published peptide Smp 126160-438-452 had an acceptable diagnostic performance with an AUC value of 0.7115 (95% CI 0.605-0.82218).…”

“…One way to mitigate the crossreactivity challenge and increase specificity is to use bioinformatic and proteomics tools to predict schistosome specific immunodominant B-cell epitopes with little or no sequence identity to proteins other than the target (4,14,16). However, to date, only a limited number of linear B-cell epitopes have been identified for the serological diagnosis of S. haematobium and S. mansoni (17)(18)(19). It is against this background that we present an approach for predicting schistosome specific peptides mimicking linear B-cell epitopes using in-silico tools and peptide microarray technology.…”