Crafting Immunological Response Using Particulate Vaccines.

To achieve optimal immunogenicity, particulates present a promising vehicle for antigen delivery and have the potential to skew immune response. Particulate vaccine offers several advantages including targeting of antigen to sentinel cells, protection from degradation, sustained release, and itself acts an adjuvant mimics viral structure. Adjuvant presence is vital in overcoming the poor immunogenicity of vaccines, e.g., subunit vaccines. Adjuvants have antigen dose sparing potential and provide danger signals to alert the immune system. Various particulate carriers received attention in the delivery of vaccine antigens such as virus-like particles, liposomes, immunostimulating complexes, and polymeric particles. This review also discussed the properties of particles such as size, shape, and rigidity affecting the immunological outcome. It further highlights the cellular uptake of the particulate vaccine, antigen processing, and its presentation by antigen-presenting cells. For mass vaccination, especially in countries lacking resources, effect of storage temperature condition on stability of vaccine is pivotal. The current COVID-19 pandemic is not showing any signs of abatement and role of nanocarriers are highly relevant in SARS-CoV-2 pandemic as an effective immunization strategy. Eradication of pandemic demands the rapid evaluation of multiple approaches that can provides successful vaccination platform, enabling scalability and global distribution.