Codelivery of SARS-CoV-2 Prefusion-Spike Protein with CBLB502 by a Dual-Chambered Ferritin Nanocarrier Potentiates Systemic and Mucosal Immunity.

Thousands of breakthrough infections are confirmed after intramuscular (i.m.) injection of the approved vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Two major factors might contribute to breakthrough infections. One is the emergence of mutant variants of SARS-CoV-2, and the other is that i.m. injection has an inefficient ability to activate mucosal immunity in the upper respiratory tract. Here, we devised a dual-chambered nanocarrier that can codeliver the adjuvant CBLB502 with prefusion-spike (pre-S) onto a ferritin nanoparticle. This vaccine enabled enhanced systemic and local mucosal immunity in the upper and lower respiratory tract. Further, codelivery of CBLB502 with pre-S induced a Th1/Th2-balanced immunoglobulin G response. Moreover, the codelivery nanoparticle showed a Th1-biased cellular immune response as the release of splenic INF-γ was significantly heightened while the level of IL-4 was elevated to a moderate extent. In general, the developed dual-chambered nanoparticle can trigger multifaceted immune responses and shows great potential for mucosal vaccine development.

Intratumoral delivery of a novel oncolytic adenovirus encoding human antibody against PD-1 elicits enhanced antitumor efficacy.

To date, diverse combination therapies with immune checkpoint inhibitors (ICIs), particularly oncolytic virotherapy, have demonstrated enhanced therapeutic outcomes in cancer treatment. However, high pre-existing immunity against the widely used adenovirus human serotype 5 (AdHu5) limits its extensive clinical application. In this study, we constructed an innovative oncolytic virus (OV) based on a chimpanzee adenoviral vector with low seropositivity in the human population, named AdC68-spE1A-αPD-1, which endows the parental OV (AdC68-spE1A-ΔE3) with the ability to express full-length anti-human programmed cell death-1 monoclonal antibody (αPD-1). In vitro studies indicated that the AdC68-spE1A-αPD-1 retained parental oncolytic capacity, and αPD-1 was efficiently secreted from the infected tumor cells and bound exclusively to human PD-1 (hPD-1) protein. In vivo, intratumoral treatment with AdC68-spE1A-αPD-1 resulted in significant tumor suppression, prolonged overall survival, and enhanced systemic antitumor memory response in an hPD-1 knockin mouse tumor model. This strategy outperformed the unarmed OV and was comparable with combination therapy with intratumoral injection of AdC68-spE1A-ΔE3 and systemic administration of commercial αPD-1. In summary, AdC68-spE1A-αPD-1 is a cost-effective approach with potential clinical applications. ‬‬‬‬.

Nitric Oxide Is Associated With Heterosis of Salinity Tolerance in Brassica napus L.

Heterosis is most frequently manifested as the superior performance of a hybrid than either of the parents, especially under stress conditions. Nitric oxide (NO) is a well-known gaseous signaling molecule that acts as a functional component during plant growth, development, and defense responses. In this study, the Brassica napus L. hybrid (F1, NJ4375 × MB1942) showed significant heterosis under salt stress, during both germination and post-germination periods. These phenotypes in the hybrid were in parallel with the better performance in redox homeostasis, including alleviation of reactive oxygen species accumulation and lipid peroxidation, and ion homeostasis, evaluated as a lower Na/K ratio in the leaves than parental lines. Meanwhile, stimulation of endogenous NO was more pronounced in hybrid plants, compared with parental lines, which might be mediated by nitrate reductase. Proteomic and biochemical analyses further revealed that protein abundance related to several metabolic processes, including chlorophyll biosynthesis, proline metabolism, and tricarboxylic acid cycle metabolism pathway, was greatly suppressed by salt stress in the two parental lines than in the hybrid. The above responses in hybrid plants were intensified by a NO-releasing compound, but abolished by a NO scavenger, both of which were matched with the changes in chlorophyll and proline contents. It was deduced that the above metabolic processes might play important roles in heterosis upon salt stress. Taken together, we proposed that heterosis derived from F1 hybridization in salt stress tolerance might be mediated by NO-dependent activation of defense responses and metabolic processes.

Adenovirus delivery of encoded monoclonal antibody protects against different types of influenza virus infection.

Due to the high mutation and recombination rates of the influenza virus, current clinically licensed influenza vaccines and anti-influenza drugs provide limited protection against the emerging influenza virus epidemic. Therefore, universal influenza vaccines with high efficacy are urgently needed to ensure human safety and health. Passive immunization of influenza broadly neutralizing antibodies may become an ideal option for controlling influenza infection. CR9114 isolated from the peripheral blood mononuclear cells of healthy donors is a broadly neutralizing monoclonal antibody that targets different types of influenza viruses. As the adenovirus vector is one of the most promising delivery vehicles, we employed the chimpanzee adenoviral vector, AdC68, to express CR9114 as a universal anti-influenza vaccine, termed AdC68-CR9114, and evaluated its antibody expression and its broad spectrum of prophylactic and therapeutic effects in animal models. Based on our findings, AdC68-CR9114-infected cell expressed the broadly neutralizing antibody at a high level in vitro and in vivo, exhibited biological functions, and protected mice from different types of influenza virus infection at different time points. The findings from this study shed light on a new strategy for controlling and preventing influenza infection.

Versatile Functionalization of Ferritin Nanoparticles by Intein-Mediated Trans-Splicing for Antigen/Adjuvant Co-delivery.

Self-assembling protein nanoparticles are extensively and increasingly engineered to integrate adjuvants with antigens to elicit potent and long-term immunity due to uniform architecture, inherent biocompatibility, and excellent plasticity. However, functionalization of nanoparticles by surface tailoring has two common problems: (1) disassembly caused by loaded cargoes; and (2) an adjuvant that is inconvenient to co-deliver with an antigen by genetic fusion. Here, we report an intein-mediated trans-splicing approach that overcomes the detrimental effects of loaded proteins on ferritin nanoparticle stability and allows concurrent display of antigen and adjuvant in a facile, efficient, and site-specific manner. An immunization study with an epitope-based model antigen reveals that antigen and adjuvant co-delivery nanoparticles induce a more potent protective immunity than other formulations do. Our results demonstrate that protein engineering represents an intriguing approach for antigen/adjuvant co-delivery to potentiate antigen-associated immune responses.