Journal Article

Unveiling promising immunogenic targets in Coxiella burnetii through in silico analysis: paving the way for novel vaccine strategies

Kodori, Mansoor, Ahmadi, Ali, Amani, Jafar

2023

Overview

Background Coxiella burnetii , an intracellular pathogen, serves as the causative agent of zoonotic Q fever. This pathogen presents a significant threat due to its potential for airborne transmission, environmental persistence, and pathogenicity. The current whole-cell vaccine (WCV) utilized in Australia to combat Q fever exhibits notable limitations, including severe adverse reactions and limited regulatory approval for human use. This research employed the reverse vaccinology (RV) approach to uncover antigenic proteins and epitopes of C. burnetii , facilitating the development of more potent vaccine candidates. Methods The potential immunogenic proteins derived from C. burnetii RSA493/Nine Mile phase I (NMI) were extracted through manual, automated RV, and virulence factor database (VFDB) methods. Web tools and bioinformatics were used to evaluate physiochemical attributes, subcellular localization, antigenicity, allergenicity, human homology, B-cell epitopes, MHC I and II binding ratios, functional class scores, adhesion probabilities, protein-protein interactions, and molecular docking. Results Out of the 1850 proteins encoded by RSA493/NMI, a subset of 178 demonstrated the potential for surface or membrane localization. Following a series of analytical iterations, 14 putative immunogenic proteins emerged. This collection included nine proteins (57.1%) intricately involved in cell wall/membrane/envelope biogenesis processes (CBU_0197 (Q83EW1), CBU_0311 (Q83EK8), CBU_0489 (Q83E43), CBU_0939 (Q83D08), CBU_1190 (P39917), CBU_1829 (Q83AQ2), CBU_1412 (Q83BU0), CBU_1414 (Q83BT8), and CBU_1600 (Q83BB2)). The CBU_1627 (Q83B86 ) (7.1%) implicated in intracellular trafficking, secretion, and vesicular transport, and CBU_0092 (Q83F57) (7.1%) contributing to cell division. Additionally, three proteins (21.4%) displayed uncharacterized functions (CBU_0736 (Q83DJ4), CBU_1095 (Q83CL9), and CBU_2079 (Q83A32)). The congruent results obtained from molecular docking and immune response stimulation lend support to the inclusion of all 14 putative proteins as potential vaccine candidates. Notably, seven proteins with well-defined functions stand out among these candidates. Conclusions The outcomes of this study introduce promising proteins and epitopes for the forthcoming formulation of subunit vaccines against Q fever, with a primary emphasis on cellular processes and the virulence factors of C. burnetii .

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Allergenicity / Amino acids / Analysis / Animals / Antigenic determinants / Antigenicity / Antigens / Binding sites / Bioinformatics / Cell division / Cell walls / Chronic fatigue syndrome / Complications and side effects / Coxiella burnetii / Disease transmission / Dosage and administration / Epitopes / Homology / Immune response / Immune system / Immunogenic proteins / Immunogenicity / Infections / Infectious Diseases / Internal Medicine / Intracellular / Localization / Lymphocytes B / Major histocompatibility complex / Mathematical analysis / Medical Microbiology / Medicine / Medicine & Public Health / Membranes / Molecular docking / Parasitology / Pathogenicity / Pathogens / Peptides / Physiochemistry / Prevention / Protein interaction / Protein-protein interactions / Proteins / Q Fever / Reverse vaccinology / Rickettsial diseases / Risk factors / Tropical Medicine / Vaccines / Virulence / Virulence factors