NANOTECHNOLOGY AND VACCINE
The history of infectious disease in humans is a core issue between host and parasite and host and pathogen (Nasir, 2008). Its effects are mainly severe in emerging nations where burden falls on the poor. The five utmost diseases are infectious or parasitic. The development of vaccine proved to be very beneficial in the history of controlling diseases. Number of vaccines is increasing day by day. (Delany et al., 2014). Nano-technology helps a lot in the field of medicine by developing nanoparticles of different composition, shapes and sizes. (Zhao et al., 2011). Table 1 below describes the overall mortality rates worldwide due to infectious diseases.
Table 1 Overall mortality rates worldwide
Nanoparticles because of their small size enter into the cell via endocytosis in particular pinocytosis. (Treuel et al., 2013). In the past decade, the use of technology of nanoparticles in vaccine in development has been expanding leading to a new discipline, nanovaccinology. (Mamo& Poland, 2012).
1.2 Nanoparticles as delivery system
In order to increase antigen processing nanoparticles are used and to improve immunity to improve immunity they may be used as adjuvant. Various Nanoparticles have been designed and discovered for their use in promoting safe immune response. Occasionally, inadequate adjuvant action might be the cause of incomplete immunogenicity. Both an antigen and an adjuvant are collectively delivered by means of nanocarriers revealed by some studies (Dunkl et al., 2013). The main purpose of nanocarriers is to ease the directing along with assist in safe approach of adjuvants to APCs. Working mechanisms of nano vaccines support the use of Nanoparticles in the field of vaccines. Dendritic cells and macrophages readily take up the particles which are smaller than 10 mm. This property demonstrated to advance cellular uptake of antigens to increase their recognition and presentation. (Oyewumi et al., 2010).
1.3 Solid nanocarriers for protein-based vaccines
Protein based antigen vaccines are protected degradation by the use of solid nanocarriers. External altered nanotransporters help in the battered delivery of antigens. Mannose receptors, scavenger receptors and toll like receptors (TLR) are included in surface receptors. (Apostolopoulos et al., 2013).
These nanotrasporters might mark the over stated receptors to progress the competence of antigen and adjuvant delivery in the direction of an appropriate immune responses in prophylactic vaccines. Antigen processing and activation of professional APCs such as dendritic cells (DC) are required for immune responses.
1.5 Nano vaccines consideration charecteristics
For cell mediated immune responses, before antigen present to naive CTLs, it must be shunted into cytoplasmic major histocompatibility class (MHC-1) pathway. New vaccines are generated continuously to cure different diseases. Several types of substances like chemical drugs, proteins as well as vaccines can be delivered by Nanoparticles delivery systems to fulfil the criteria of high bioavailability, sustained and controlled release profiles, targeting, imaging and so forth (Lepenie et al., 2013). Figure 1 below describes the considerations to develop a potent and efficient vaccine.
Figure 1 Considerations for effective and potent vaccine
DIFFERENT NANODELIVERY SYSTEMS USED TO DELIVER VACCCINE
Self closed vesicle like structures that entrap water in their interior are called liposomes. Amphiphiles self assembled to form these structures. The series of width of liposomes is from 20 nm to numerous hundreds of nm whereas the width of phospholipid bilayers membrane is about 4-7 nm (Pinheiro et al., 2011) Antigen is encapsulated within the core of liposomes for delivery. (Giddam et al., 2012).
2.1.1 LPD AND ICMVs