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The Coalition for Epidemic Preparedness Innovations' "100‐day moonshot" aspires to launch a new vaccine within 100 days of pathogen identification, followed by large‐scale vaccine availability within the "second hundred days." Here, we describe work to optimize adenoviral vector manufacturing for rapid response, by minimizing time to clinical trial and first large‐scale supply, and maximizing output from the available manufacturing footprint. We describe a rapid virus seed expansion workflow that allows vaccine release to clinical trials within 60 days of antigen sequence identification, followed by vaccine release from globally distributed sites within a further 40 days. We also describe a perfusion‐based upstream production process, designed to maximize output while retaining simplicity and suitability for existing manufacturing facilities. This improves upstream volumetric productivity of ChAdOx1 nCoV‐19 by approximately fourfold and remains compatible with the existing downstream process, yielding drug substance sufficient for 10,000 doses from each liter of bioreactor capacity. This accelerated manufacturing process, along with other advantages such as thermal stability, supports the ongoing value of adenovirus‐vectored vaccines as a rapidly adaptable and deployable platform for emergency response. [ABSTRACT FROM AUTHOR]

Plasmodium sporozoites are extracellular forms introduced during mosquito bite that selectively invade mammalian hepatocytes. Sporozoites are delimited by a cell membrane that is linked to the underlying acto‐myosin molecular motor. While membrane proteins with roles in motility and invasion have been well studied, very little is known about proteins that maintain the sporozoite shape. We demonstrate that in Plasmodium berghei (Pb) a conserved hypothetical gene, PBANKA_1422900 specifies sporozoite structural integrity maintenance protein (SIMP) required for maintaining the sporozoite shape and motility. Sporozoites lacking SIMP exhibited loss of regular shape, extensive membrane blebbing at multiple foci, and membrane detachment. The mutant sporozoites failed to infect hepatocytes, though the altered shape did not affect the organization of cytoskeleton or inner membrane complex (IMC). Interestingly, the components of IMC failed to extend under the membrane blebs likely suggesting that SIMP may assist in anchoring the membrane to IMC. Endogenous C‐terminal HA tagging localized SIMP to membrane and revealed the C‐terminus of the protein to be extracellular. Since SIMP is highly conserved among Plasmodium species, these findings have important implications for utilizing it as a novel sporozoite‐specific vaccine candidate. [ABSTRACT FROM AUTHOR]

Manufacturing has been the key factor limiting rollout of vaccination during the COVID‐19 pandemic, requiring rapid development and large‐scale implementation of novel manufacturing technologies. ChAdOx1 nCoV‐19 (AZD1222, Vaxzevria) is an efficacious vaccine against SARS‐CoV‐2, based upon an adenovirus vector. We describe the development of a process for the production of this vaccine and others based upon the same platform, including novel features to facilitate very large‐scale production. We discuss the process economics and the "distributed manufacturing" approach we have taken to provide the vaccine at globally‐relevant scale and with international security of supply. Together, these approaches have enabled the largest viral vector manufacturing campaign to date, providing a substantial proportion of global COVID‐19 vaccine supply at low cost. [ABSTRACT FROM AUTHOR]

Rabies virus (RABV) causes lethal encephalitis and is responsible for approximately 60,000 deaths per year. As the sole virion-surface protein, the rabies virus glycoprotein (RABV-G) mediates host-cell entry. RABV-G's pre-fusion trimeric conformation displays epitopes bound by protective neutralizing antibodies that can be induced by vaccination or passively administered for post-exposure prophylaxis. We report a 2.8-Å structure of a RABV-G trimer in the pre-fusion conformation, in complex with two neutralizing and protective monoclonal antibodies, 17C7 and 1112-1, that recognize distinct epitopes. One of these antibodies is a licensed prophylactic (17C7, Rabishield), which we show locks the protein in pre-fusion conformation. Targeted mutations can similarly stabilize RABV-G in the pre-fusion conformation, a key step toward structure-guided vaccine design. These data reveal the higher-order architecture of a key therapeutic target and the structural basis of neutralization by antibodies binding two key antigenic sites, and this will facilitate the development of improved vaccines and prophylactic antibodies. [Display omitted] • 2.8-Å cryo-EM structure of trimeric pre-fusion rabies virus glycoprotein • Structure reveals trimerization interface and binding of two neutralizing antibodies • Conformational transition can be inhibited by both antibodies and targeted mutation Ng, Fedosyuk et al. present the structure of a complex of pre-fusion trimeric rabies glycoprotein (RABV-G) with two neutralizing antibodies, one of which (17C7) is used clinically for post-exposure prophylaxis. They show that 17C7 inhibits pre- to post-fusion conformational transition, and they identify amino acid substitutions with a similar effect. [ABSTRACT FROM AUTHOR]

Plasmodium sporozoites are extracellular forms introduced during mosquito bite that selectively invade mammalian hepatocytes. Sporozoites are delimited by a cell membrane that is linked to the underlying acto-myosin molecular motor. While membrane proteins with roles in motility and invasion have been well studied, very little is known about proteins that maintain the sporozoite shape. We demonstrate that in Plasmodium berghei (Pb) a conserved hypothetical gene, PBANKA_1422900 specifies sporozoite structural integrity maintenance protein (SIMP) required for maintaining the sporozoite shape and motility. Sporozoites lacking SIMP exhibited loss of regular shape, extensive membrane blebbing at multiple foci, and membrane detachment. The mutant sporozoites failed to infect hepatocytes, though the altered shape did not affect the organization of cytoskeleton or inner membrane complex (IMC). Interestingly, the components of IMC failed to extend under the membrane blebs likely suggesting that SIMP may assist in anchoring the membrane to IMC. Endogenous C-terminal HA tagging localized SIMP to membrane and revealed the C-terminus of the protein to be extracellular. Since SIMP is highly conserved among Plasmodium species, these findings have important implications for utilizing it as a novel sporozoite-specific vaccine candidate., (© 2022 John Wiley & Sons Ltd.)