Epitope mapping of pathogenicLeptospiraLipL32

Abstract

Aims: To identify LipL32 epitopes and to evaluate their capability to recognize specific antibodies using ELISA. Methods and Results: Epitope mapping by means of a library of overlapping peptide fragments prepared by simultaneous and parallel solid phase peptide synthesis on derivatized cellulose membranes (SPOT synthesis) was carried out. Eighty‐seven overlapping decapentapeptides corresponding to the complete sequence of LipL32 were synthesized. According to spot‐image intensities, the most reactive sequences were localized in regions 151–177 (sequence AAKAKPVQKLDDDDDGDDTYKEERHNK) and 181–204 (sequence LTRIKIPNPPKSFDDLKNIDTKKL). Two peptides (P1 and P2) corresponding to these sequences were synthesized, and their reactivity evaluated using ELISA test. Conclusions: Epitope identification and analysis suggested the existence of two antigenic regions within LipL32. These LipL32 reactive regions were highly conserved among antigenically variants of Leptospira spp. isolates. Peptides containing these regions (P1 and P2) showed a good capability for anti‐leptospiral antibody recognition. Significance and Impact of the Study: This finding could have potential relevance not only for serodiagnosis but also as a starting point for the characterization of targets for vaccine design.

Crystal Structure of LipL32, the Most Abundant Surface Protein of Pathogenic Leptospira spp.

“…38 Recently, human antibody epitopes have been characterized for LipL32. 29 They consist of residues 132-158 and 162-186 ( Fig. 5c and d).…”

“…The LipL32 structure is shown in cartoon representation in green with residues 132-158 shown in pink. 29 (d) Epitope 2. The LipL32 structure is shown in cartoon representation in green with residues 162-186 shown in pink.…”

“…The LipL32 structure is shown in cartoon representation in green with residues 162-186 shown in pink. 29 redundancy in ECM adhesion would convey a selective advantage to Leptospira during the initial infection stage as 95% of human patients with leptospirosis produce antibodies against LipL32. 14 Many bacterial adhesins can be effective vaccine candidates, such as Hap adhesin from Haemophilus influenzae and collagen adhesin from Staphylococcus aureus.…”

Mapping of Epitopes Recognized by Antibodies Induced by Immunization of Mice with PspA and PspC

“…We previously used a similar method to compare sera from mice immunized with one PspA variant as a recombinant protein and as a DNA vaccine (34). This technique has also been used successfully to screen epitopes of antigens from other pathogens (35,36). The present study tested sera from mice immunized with several variants of PspA and PspC3 to identify the most immunogenic epitopes.…”

Bioinformatics and <i>in-silico</i> epitope prediction analysis of highly conserved pathogenic <i>Leptospira</i> genes

“…Due to their inability to elicit long term immunity against different pathogenic serovars, efforts have shifted to search for subunit vaccine candidates that can provide heterologous protection (Zuerner et al, 2000). Several outer membrane proteins and immunoglobulin-like proteins have been reported to provide protection against challenge with several Leptospira organisms (Lottersberger et al, 2009). Many of the protections claimed are not clear cut, due to inappropriate statistical analysis, inadequate challenge dose and virulence of the challenge strain and number of animals used (Adler and Klaasen, 2015).…”