## 1 Introduction  
_Neisseria meningitidis_ is a diplococcal Gram-negative bacterial species that serves as the predominant causative infectious agent for a range of diseases classified as an invasive meningococcal disease [1]. Meningitis is defined as the infection of the meninges membranes encompassing the brain and spinal cord. _N. meningitidis_ is an obligate human pathogen [2] and its infections may remain asymptomatic [3]. Meningitis progression is rapid and has complicated symptoms that make clinical diagnosis difficult and cause it to be a world-wide challenge to treat and prevent.  
_N. meningitidis_ is host-specific and adapted to sidestep the human immune system during pathogenesis as well as having commensal residence in the nasopharynx [2]. The human immune system is complex and can eliminate the meningococcus infection through an array of different strategies, including antimicrobial peptides and proteins, which play an important role in the innate immune system [4]. To combat the host antibacterial defense system, _N. meningitidis_ modifies lipidA-groups of the toxins lipooligosaccharides through phosphoethanolamine [5]. The compounds present in the outer membrane increase meningococcal resistance against the human microbial peptide LL-37 [6]. As reported previously, a number of factors (e.g., biofilm formation ability, adherence to the cell, and the ability to invade host cells) are important for the virulence of this bacterium [7], while iron acquisition is another virulence factor and determinant of host cell death [8].  
According to Centers for Disease Control and Prevention (CDC), there are two types of meningococcal vaccines available in the United States: meningococcal conjugate vaccine and serogroup B meningococcal vaccine. The former is recommended for 11 to 12 years old person while requiring to administer a booster dose after three to four years. On the other hand, the latter is for 10 years or older ([[https://www.cdc.gov/vaccines/vpd/mening/index.html](https://www.cdc.gov/vaccines/vpd/mening/index.html)]([https://www.cdc.gov/vaccines/vpd/mening/index.html](https://www.cdc.gov/vaccines/vpd/mening/index.html))). However, outer membrane protein vaccines have been observed to have high efficacy against group B in individuals over 4 years of age [9]. On the other hand, _N. meningitidis_ is found to have low genomic stability. In light of all these factors, a stable, multi-purpose vaccine against _N. meningitidis_ is in urgent need for development.  
Acquisition of iron is an important factor for the virulence of pathogens such as _N. meningitidis_[10]. If restricted, pathogenic bacteria require major transcriptional changes to amplify and transcript iron metabolic- and motility-related genes. Proteomic analysis may facilitate vaccine design through a better understanding of energy and metabolic processes as well as iron storage [11]. Proteomics bioinformatic tools are valuable for epitope prediction and vaccine design based on 3D proteomic structuring [12; 13; 14]. In the present study, we combine _in silico_ analyses of the _N. meningitidis_ genome structure with bioinformatic tools to identify potentially immunogenic antigens from _N. meningitidis_ proteins. We verify the iron-regulated proteins from _N. meningitidis_ and investigate the potential of iron-regulated proteins as candidates for the development of an _N. meningitidis_ vaccine. Furthermore, our systematic selection and evaluation of antigens provide a new approach that will help lower the expense of cloning.