The rise of nanovaccine technology: strategies to improve immune response to nanovaccines: P1

Vaccines are an unparalleled medical milestone, which have saved countless lives by harnessing the human immune system. Vaccination remained the most effective means of defense during the COVID-19 pandemic in 2019. The success of lipid nanoparticle (LNP)-delivered mRNA vaccines shows that nanotechnology can be used in vaccine development.

In terms of lymph node accumulation, antigen assembly, and antigen presentation, nanovaccines outperform traditional vaccines. They also have unique pathogenic bionic properties due to the ordered combination of multiple immune factors. In addition to infectious diseases, nanovaccine technology has shown great potential for the treatment of cancer.

The ultimate goal of cancer vaccines is to mobilize the immune system to its full potency to recognize tumor antigens and eliminate tumor cells, and nanotechnology has the properties necessary to achieve this goal. As one of the candidates for cancer immunotherapy with customizable components and sequential integration, nanovaccine technology will likely be a strategy and platform to achieve more effective activation of anti-tumor immunity.

Types of nanomaterial-based vaccines

Various nanomaterials, such as lipid nanoparticles, protein nanoparticles, polymer nanoparticles, inorganic nanocarriers, and bionanoparticles, have been investigated for vaccine development in recent years. Varied types of nanocarriers have different physicochemical properties and in vivo behaviors, which have an impact on vaccination.

Self-assembled protein nanoparticles

Natural nanomaterials have good biocompatibility and biodegradability. Several types of protein nanoparticles made from proteins of natural origin have been used for the delivery of antigens. Self-assembled protein nanoparticles are promising candidates for nanovaccines. Typical examples of self-assembled protein nanoparticles include ferritin family protein, pyruvate dehydrogenase (E2), and virus-like particle (VLP), which show great potential in vaccine development.

Polymer nanoparticles

Polymer nanoparticles are colloidal systems with a wide size range (10-1000 nm), which are highly immunogenic and stable, and can effectively encapsulate and display antigens. Polymeric nanoparticles can improve the efficiency of antigen uptake by APC through phagocytosis or endocytosis.

Lipid nanoparticles

Lipid nanoparticles are nanoscale lipid vesicles formed by self-assembly of amphiphilic phospholipid molecules. LNPs are a viable nanocarrier for nucleic acid delivery because of their low toxicity, great biocompatibility, and controlled release features.

Inorganic nanomaterials

Metals and oxides, non-metallic oxides, and inorganic salts are examples of inorganic materials commonly used in nanomedicine. Inorganic materials are structurally stable and have low biodegradability. However, in order to improve biocompatibility, alterations to the physicochemical properties of inorganic nanomaterials are required for nanovaccine applications. Gold, iron, and silica nanoparticles are the most commonly employed inorganic materials for antigen delivery.

Biomimetic nanomaterials

Biomimetic nanomaterials are versatile and can be used to transmit tailored messages or interact with biological systems. To generate effective vaccine formulations, biologically inspired nanoparticles with excellent biocompatibility and unique antigenicity can be employed.

In the development of nanovaccines to fight infection and cancer, several different bionic strategies have arisen. Virosomes are 60-200 nm liposomal haploid nanocarriers that use the liposome principle but have a structure similar to an enveloped virus without the nucleocapsid. Virosomes are a new type of bionanoparticle that could be used to develop nanovaccines to fight viral infections. Outer membrane vesicles (OMVs) are bacterial nanovesicles that carry proteins similar to those found in bacteria's outer membrane. Because of its multi-antigenic properties, OMV is a natural antibacterial vaccine.

Natural ligands or peptides, such as RGD and CDX peptides, are used to alter nanoparticles and improve binding to improve targeting for effective administration in a simple biomimetic design. In addition, molecularly imprinted polymers can be employed to generate bionanoparticles by mimicking antibodies.

A fan of biotechnology who likes to post articles in relevant fields regularly