Vaccination is a method of stimulating resistant in the human body to specific diseases using microorganisms (bacteria or viruses) that have been modified or killed. Currently, the available vaccines are composed of killed or life attenuated the whole pathogens before being injected to the human body. Despite the advantages of such vaccines, there are a lot of potential safety problems such as incomplete inactivation of the killed pathogens or the evolution of the attenuated virus. Instead of the entire microbe, subunit vaccines include only the antigens that best stimulate the immune system....