Document text
Principal Investigator: Guizhi Zhu
Organization: VIRGINIA COMMONWEALTH UNIVERSITY
Fiscal Year: 2023
Award: $552,247
Funding agency: National Institute of Allergy and Infectious Diseases
Small circular mRNA vaccines
Abstract:
Vaccines save numerous lives each year. Conventional vaccines based on pathogens, DNA, proteins, or
peptides are associated with poor pharmacokinetics, limited biostability, preexisting anti-viral-vector immunity,
weak immunogenicity, or safety concerns over genomic integration or virulent reversion. The emerging mRNA
vaccines hold the potential to overcome the above issues with pharmacokinetics and safety using mRNA and
advanced drug delivery systems. However, despite efficient delivery, current mRNA vaccines rely on long mRNA
that is still associated with 1) limited biostability, though extensively modified, and the resulting limited shelf-life
even using cold chains and poor antigen translation efficiency, and 2) complicated enzymatic production. To
address these limitations, we propose developing antigen-encoding small circular mRNA (circRNA), which are
highly biostable and efficiently delivered by existing nanocarriers, as a novel platform of mRNA vaccines. Small
circRNA is comprised of minimal RNA elements to translate peptide antigens. Our preliminary data showed
several notable features of small circRNA vaccines: 1) in contrast to long mRNA, small circRNA leverages
automated RNA synthesizers for fast, efficient, and precise chemical synthesis and versatile functional
modifications; 2) even without any biostabilizing modifications, terminus-free circRNA prevents exonuclease
degradation and prolongs its in vivo half-life and shelf-life under freezing, fridge, and ambient temperatures; as
a result, circRNA showed efficient antigen translation and immunomodulation; 3) small circRNA vaccines
leverage current drug delivery systems for efficient delivery to desired tissues and cells, and the small circRNA
sizes can increase its loading capacity in nanocarriers, relative to bulky mRNA; 4) circRNA vaccine is self-
adjuvanted due to intrinsic immunostimulation; 5) in cells, circRNA produces long genuine peptide antigens that
elicit potent immunity; and 6) the modularity of circRNA vaccine allows its easy adaption for wide application. As
a result, low-dose circRNA nanoparticles elicited potent immune responses in both young adult mice and aged
mice, protected mice from target cell challenge, and mediated robust tumor immunotherapy. In this application,
Aim 1 will optimize the antigen translation and presentation of biostable small circRNA vaccines by circRNA
engineering; Aim 2 will study nanoparticle delivery of circRNA into immune tissues and cells, and the stability,
integrity, and antigen translation kinetics of circRNA vaccines upon delivery to target cells; Aim 3 will decipher
the immunomodulation mechanism by nanoparticle-delivered small circRNA vaccines; and Aim 4 will use human
papillomavirus (HPV)-associated cancer as a test bed to assess the prophylaxis and therapeutic efficacy of
nanoparticulate small circRNA vaccine in syngeneic and transgenic mouse tumor models. The PI (Early Stage
Investigator) has assembled a team with complementary expertise to conduct this study. If successful, this study
will lay the foundation to develop circRNA as a novel platform of mRNA vaccines for wide application in the
prophylaxis and treatment of diseases, such as cancer and infectious diseases.
Page 1
Terms: <Address><Adjuvant><Antigen Presentation><Antigen Presentation Pathway><Antigen Processing and Presentation><Antigen-Presenting Cells><Antigens><Beds><Benchmarking><Best Practice Analysis><Biodistribution><Body Tissues><CD8 Cell><CD8 T cells><CD8 lymphocyte><CD8+ T cell><CD8+ T-Lymphocyte><CD8-Positive Lymphocytes><CD8-Positive T-Lymphocytes><COVID-19><COVID19><CV-19><CV19><Cancers><Cell Body><Cells><Chemicals><Chronic><Cold Chains><Communicable Diseases><Complex><DNA><Data><Deoxyribonucleic Acid><Disease><Disorder><Dose><Drug Delivery><Drug Delivery Systems><Drug Kinetics><Elements><Engineering><Exonuclease><Foundations><Freezing><Genetic Alteration><Genetic Change><Genetic defect><Genomics><Guidelines><HPV><HPV induced cancer><HPV malignancy><HPV+ cancer><HPV-Related Malignancy><HPV-associated cancer><HPV-associated malignancy><HPV-related cancer><Half-Life><Human Papilloma Virus><Human Papilloma Virus-Related Malignancy><Human Papilloma Virus-Related Malignant Neoplasm><Human Papilloma Virus-associated cancer><Human Papilloma Virus-associated malignancy><Human Papilloma Virus-related cancer><Human Papillomavirus><Human papillomavirus cancer><Human papillomavirus induced cancer><Human papillomavirus malignancy><Human papillomavirus-Related Malignancy><Human papillomavirus-Related Malignant Neoplasm><IRES><Immune><Immune response><Immunes><Immunity><Immunization><Immunologic Receptors><Immunologic Stimulation><Immunological Receptors><Immunological Stimulation><Immunological response><Immunomodulation><Immunostimulation><In Vitro><Infection><Infectious Disease Pathway><Infectious Diseases><Infectious Disorder><Infectious Human Wart Virus><Innate Immune Response><Innate Immunity><Internal Ribosome Entry Segment><Internal Ribosome Entry Site><Investigators><Kinetics><Life><Liposomal><Liposomes><Lymph Node Reticuloendothelial System><Lymph node proper><Lymphatic nodes><Malignant Neoplasms><Malignant Tumor><Maps><Mediating><Messenger RNA><Mice><Mice Mammals><Modeling><Modification><Murine><Mus><Mutate><Mutation><Native Immunity><Natural Immunity><Non-Polyadenylated RNA><Non-Specific Immunity><Nonspecific Immunity><Nucleotides><Outcome><Peptides><Pharmacokinetics><Production><Prophylactic treatment><Prophylaxis><Proteins><Proteomics><RNA><RNA Editing><RNA Gene Products><RNA vaccine><RNA, Messenger, Editing><RNA-based vaccine><Research Personnel><Researchers><Ribonucleic Acid><Ribosome Entry Site><Risk><Safety><Series><Structure><T cell response><T-Cells><T-Lymphocyte><T8 Cells><T8 Lymphocytes><Technology><Temperature><Testing><Tissues><Toxic effect><Toxicities><Transgenic Mice><Translating><Translation Initiation><Translations><Transportation><Treatment Efficacy><Vaccines><Viral Vector><Virulent><Virus><access to vaccination><access to vaccines><accessory cell><adaptive immunity><adult youth><aged><anti-tumor immune therapy><anti-tumor immunotherapy><antitumor immune therapy><antitumor immunotherapy><benchmark><chemical synthesis><circular RNA><closed circular RNA><corona virus disease 2019><coronavirus disease 2019><coronavirus disease-19><coronavirus infectious disease-19><genome mutation><host response><human papillomavirus associated malignancy><human papillomavirus-associated cancer><human papillomavirus-related cancer><immune modulation><immune receptor><immune regulation><immune system response><immunogen><immunogenicity><immunologic reactivity control><immunomodulatory><immunoregulation><immunoregulatory><immunoresponse><improved><improved outcome><in vivo><innovate><innovation><innovative><intervention efficacy><lymph gland><lymph nodes><lymphnodes><mRNA><mRNA seq><mRNA sequencing><mRNA vaccine><mRNA-based vaccine><mRNA-seq><mRNAseq><malignancy><manufacture><nano particle><nano particle delivery><nano particulate><nano-sized particle><nanocarrier><nanoparticle><nanoparticle delivered><nanoparticle delivery><nanoparticulate><nanosized particle><nanovessel><neoplasm immunotherapy><neoplasm/cancer><novel><pathogen><prevent><preventing><prophylactic><scRNA-seq><single cell RNA-seq><single cell RNAseq><single cell expression profiling><single cell transcriptomic profiling><single-cell RNA sequencing><success><therapeutic efficacy><therapy efficacy><thymus derived lymphocyte><translation><tumor><tumor immune therapy><tumor immunotherapy><vaccination access><vaccination availability><vaccine access><vaccine availability><vaccine efficacy><vector><wart virus><young adult><young adulthood>