Journal Article

A Novel Prophylaxis Strategy Using Liposomal Vaccine Adjuvant CAF09b Protects against Influenza Virus Disease

Zimmermann, Julie, Cox, Rebecca, Schmidt, Signe, Zhou, Fan, Christensen, Dennis, Pedersen, Gabriel, Follmann, Frank, Trebbien, Ramona

2022

Overview

The SARS-CoV-2 pandemic caused a massive health and societal crisis, although the fast development of effective vaccines reduced some of the impact. To prepare for future respiratory virus pandemics, a pan-viral prophylaxis could be used to control the initial virus outbreak in the period prior to vaccine approval. The liposomal vaccine adjuvant CAF®09b contains the TLR3 agonist polyinosinic:polycytidylic acid, which induces a type I interferon (IFN-I) response and an antiviral state in the affected tissues. When testing CAF09b liposomes as a potential pan-viral prophylaxis, we observed that intranasal administration of CAF09b liposomes to mice resulted in an influx of innate immune cells into the nose and lungs and upregulation of IFN-I-related gene expression. When CAF09b liposomes were administered prior to challenge with mouse-adapted influenza A/Puerto Rico/8/1934 virus, it protected from severe disease, although the virus was still detectable in the lungs. However, when CAF09b liposomes were administered after influenza challenge, the mice had a similar disease course to controls. In conclusion, CAF09b may be a suitable candidate as a pan-viral prophylactic treatment for epidemic viruses, but must be administered prior to virus exposure to be effective.

• Publisher: MDPI AG,MDPI
• Subject: Adjuvants, Immunologic - administration & dosage / Adjuvants, Immunologic - therapeutic use / Adjuvants, Vaccine - administration & dosage / Adjuvants, Vaccine - chemistry / Adjuvants, Vaccine - pharmacology / Adjuvants, Vaccine - therapeutic use / Administration, Intranasal / Animals / Antiviral drugs / Cells, Cultured / Chick Embryo / COVID-19 - prevention & control / COVID-19 Vaccines - chemical synthesis / COVID-19 Vaccines - therapeutic use / Disease prevention / Epidemics / Gene Expression Regulation - drug effects / Humans / Immune system / Infections / Influenza / Influenza Vaccines - administration & dosage / Influenza Vaccines - chemistry / Influenza Vaccines - pharmacology / Influenza Vaccines - therapeutic use / Influenza, Human - prevention & control / Interferon Type I - genetics / Liposomes - chemistry / Mice / Mice, Inbred BALB C / Mice, Inbred C57BL / Mutation / Orthomyxoviridae Infections - prevention & control / Pandemics / Phase transitions / Primary Prevention - methods / SARS-CoV-2 - immunology / Severe acute respiratory syndrome coronavirus 2 / Vaccine Development - methods / Vaccines / Viral infections / Viruses