The impact of nucleoside base modification in mRNA vaccine is influenced by the chemistry of its lipid nanoparticle delivery system.

The use of modified nucleosides is an important approach to mitigate the intrinsic immunostimulatory activity of exogenous mRNA and to increase its translation for mRNA therapeutic applications. However, for vaccine applications, the intrinsic immunostimulatory nature of unmodified mRNA could help induce productive immunity. Additionally, the ionizable lipid nanoparticles (LNPs) used to deliver mRNA vaccines can possess immunostimulatory properties that may influence the impact of nucleoside modification.

Specific immuno-imaging of pulmonary-resident memory lymphocytes in human lungs.

Introduction: Pulmonary-resident memory T cells (T) and B cells (B) orchestrate protective immunity to reinfection with respiratory pathogens. Developing methods for the detection of these populations would benefit both research and clinical settings.

Methods: To address this need, we developed a novel immunolabelling approach combined with clinic-ready fibre-based optical endomicroscopy (OEM) to detect canonical markers of lymphocyte tissue residency in human lungs undergoing lung ventilation (EVLV).

Inhibitory effect of concomitantly administered rabies immunoglobulins on the immunogenicity of commercial and candidate human rabies vaccines in hamsters.

The World Health Organization protocol for rabies post-exposure prophylaxis (PEP) recommends extensive wound washing, immediate vaccination, and administration of rabies immunoglobulin (RIG) in severe category III exposures. Some studies have shown that RIG can interfere with rabies vaccine immunogenicity to some extent. We investigated the interference of RIG on a next generation highly purified Vero cell rabies vaccine candidate (PVRV-NG) versus standard-of-care vaccines in a previously described hamster model.

A novel vaccine adjuvant based on straight polyacrylate potentiates vaccine-induced humoral and cellular immunity in cynomolgus macaques.

Adjuvants are central to the efficacy of subunit vaccines. Although several new adjuvants have been approved in human vaccines over the last decade, the panel of adjuvants in licensed human vaccines remains small. There is still a need for novel adjuvants that can be safely used in humans, easy to source and to formulate with a wide range of antigens and would be broadly applicable to a wide range of vaccines.

An optimized purified inactivated Zika vaccine provides sustained immunogenicity and protection in cynomolgus macaques.

The recent spread of Zika virus (ZIKV) through the Americas and Caribbean and its devastating consequences for pregnant women and their babies have driven the search for a safe and efficacious ZIKV vaccine. Among the vaccine candidates, a first-generation ZIKV purified inactivated vaccine (ZPIV), adjuvanted with aluminum hydroxide, developed by the Walter Reed Army Institute of Research (WRAIR), has elicited high seroconversion rates in participants in three phase-I clinical trials. In collaboration with the WRAIR, Sanofi Pasteur (SP) optimized the production scale, culture and purification conditions, and increased the regulatory compliance, both of which are critical for clinical development and licensure of this vaccine.