Antigen-coated poly α-hydroxy acid based microparticles for heterologous prime-boost adenovirus based vaccinations

Abstract

Adenoviruses show promising potential as vectors for cancer vaccines, however, their high immunogenicity can be problematic when it comes to homologous prime-boost strategies. In the studies presented here we show that heterologous prime-boost vaccinations involving ovalbumin (OVA)-antigen coated microparticles as a prime, and adenovirus encoding OVA (Ad-OVA) as a boost, were equally as effective as homologous Ad-OVA prime-boosts at generating OVA-specific CD8+ T cell responses, which translated into effective tumor protection. OVA-coated biodegradable poly α-hydroxy acid based microparticles of varying chemistries, when used as primes in heterologous prime-boost vaccinations, were comparable in terms of promoting OVA-specific CD8+ T cells as well as providing protection against subsequent tumor challenge. These findings auger well for using poly α-hydroxy acid based microparticles in prime-boost viral vaccination strategies geared toward the safer, and potentially more efficient, generation of anti-tumor immunity.

Polydopamine as the Antigen Delivery Nanocarrier for Enhanced Immune Response in Tumor Immunotherapy

“…At present, most of the nanoparticulated vaccine formulations are designed following two strategies: the antigens are either encapsulated in nanoparticles (NPs) or displayed on the surface of NPs. It was reported that the antigen encapsulated in NPs by the self-assembly process induced a stronger antigen-specific immune response than the soluble antigen. , More recently, the applications of antigen-on-nanoparticle surface formulations, such as virus-like particles or protein particles, has become increasingly attractive, with numerous studies demonstrating that APC engagement with nanoparticles themselves triggers inflammatory responses. − …”

Diaminosulfide based polymer microparticles as cancer vaccine delivery systems

“…Many types of vaccine vectors have achieved varying degrees of scrutiny in the tumor immunology field and each have their advantages and disadvantages relating to issues of safety, patient compliance, financial cost, immune potency and labor intensiveness [34, 35]. Delivery of vaccines using attenuated viruses encoding tumor antigen can be a highly efficient way of generating antitumor cellular immune responses, however, such vaccines may be prone to inducing unwanted immune responses or be neutralized by the host’s own antibodies [5, 36–39]. Delivery of antigen complexed with alum tends to favor antibody responses at the expense of cellular immune responses and thus is considered unsuitable for use in cancer vaccines [40].…”

A nasal vaccine with inactivated whole-virion elicits protective mucosal immunity against SARS-CoV-2 in mice

“…In addition, these vaccines have several limitations. For example, adenovirus vector-based vaccines are ineffective at inducing adenovirus-specific antibodies following the first dose ( 40 ). Subunit vaccines require adjuvants to elicit immune responses ( 41 , 42 ) because intranasal administration of antigens alone does not elicit antigen-specific antibodies.…”