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Recombinant adeno-associated viruses (rAAVs) have emerged as promising gene therapy vectors due to their proven efficacy and safety in clinical applications. In non-human primates (NHPs), rAAVs are administered via suprachoroidal injection at a higher dose. However, high doses of rAAVs tend to increase additional safety risks. Here, we present a novel AAV capsid (AAVv128), which exhibits significantly enhanced transduction efficiency for photoreceptors and retinal pigment epithelial (RPE) cells, along with a broader distribution across the layers of retinal tissues in different animal models (mice, rabbits, and NHPs) following intraocular injection. Notably, the suprachoroidal delivery of AAVv128-anti-VEGF vector completely suppresses the Grade IV lesions in a laser-induced choroidal neovascularization (CNV) NHP model for neovascular age-related macular degeneration (nAMD). Furthermore, cryo-EM analysis at 2.1 Å resolution reveals that the critical residues of AAVv128 exhibit a more robust advantage in AAV binding, the nuclear uptake and endosome escaping. Collectively, our findings highlight the potential of AAVv128 as a next generation ocular gene therapy vector, particularly using the suprachoroidal delivery route. In non-human primates, rAAVs are delivered through suprachoroidal injection at a high dose to achieve optimal efficacy. Here, the authors present a novel AAV capsid (AAVv128) that significantly improved the transduction efficiency in photoreceptor and retinal pigment epithelial cells across species. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has caused a global coronavirus disease 2019 (COVID‐19) pandemic that has affected the lives of billions of individuals. However, the host‐virus interactions still need further investigation to reveal the underling mechanism of SARS‐CoV‐2 pathogenesis. Here, transcriptomics analysis of SARS‐CoV‐2 infection highlighted possible correlation between host‐associated signaling pathway and virus. In detail, cAMP‐protein kinase (PKA) pathway has an essential role in SARS‐CoV‐2 infection, followed by the interaction between cyclic AMP response element binding protein (CREB) and CREB‐binding protein (CBP) could be induced and leading to the enhancement of CREB/CBP transcriptional activity. The replication of Delta and Omicron BA.5 were inhibited by about 49.4% and 44.7% after knockdown of CREB and CBP with small interfering RNAs, respectively. Furthermore, a small organic molecule naphthol AS‐E (nAS‐E), which targets on the interaction between CREB and CBP, potently inhibited SARS‐CoV‐2 wild‐type (WT) infection with comparable the half‐maximal effective concentration (EC50) 1.04 μM to Remdesivir 0.57 μM. Compared with WT virus, EC50 in Calu‐3 cells against Delta, Omicron BA.2, and Omicron BA.5 were, on average, 1.5‐fold, 1.1‐fold, and 1.5‐fold higher, respectively, nAS‐E had a satisfied antiviral effect against Omicron variants. Taken together, our study demonstrated the importance of CREB/CBP induced by cAMP‐PKA pathway during SARS‐CoV‐2 infection, and further provided a novel CREB/CBP interaction therapeutic drug targets for COVID‐19. [ABSTRACT FROM AUTHOR]

The type I adenosine 5'-triphosphate (ATP)-binding cassette (ABC) transporter DppABCD is believed to be responsible for the import of exogenous heme as an iron source into the cytoplasm of the human pathogen Mycobacterium tuberculosis ( Mtb ). Additionally, this system is also known to be involved in the acquisition of tri- or tetra-peptides. Here, we report the cryo-electron microscopy structures of the dual-function Mtb DppABCD transporter in three forms, namely, the apo , substrate-bound, and ATP-bound states. The apo structure reveals an unexpected and previously uncharacterized assembly mode for ABC importers, where the lipoprotein DppA, a cluster C substrate-binding protein (SBP), stands upright on the translocator DppBCD primarily through its hinge region and N-lobe. These structural data, along with biochemical studies, reveal the assembly of DppABCD complex and the detailed mechanism of DppABCD-mediated transport. Together, these findings provide a molecular roadmap for understanding the transport mechanism of a cluster C SBP and its translocator.

The SARS-CoV-2 Omicron variant evades most currently approved neutralizing antibodies (nAbs) and caused drastic decrease of plasma neutralizing activity elicited by vaccination or prior infection, urging the need for the development of pan-variant antivirals. Breakthrough infection induces a hybrid immunological response with potentially broad, potent and durable protection against variants, therefore, convalescent plasma from breakthrough infection may provide a broadened repertoire for identifying elite nAbs. We performed single-cell RNA sequencing (scRNA-seq) and BCR sequencing (scBCR-seq) of B cells from BA.1 breakthrough-infected patients who received 2 or 3 previous doses of inactivated vaccine. Elite nAbs, mainly derived from the IGHV2-5 and IGHV3-66/53 germlines, showed potent neutralizing activity across Wuhan-Hu-1, Delta, Omicron sublineages BA.1 and BA.2 at picomolar NT 50 values. Cryo-EM analysis revealed diverse modes of spike recognition and guides the design of cocktail therapy. A single injection of paired antibodies cocktail provided potent protection in the K18-hACE2 transgenic female mouse model of SARS-CoV-2 infection., (© 2023. The Author(s).)