bioRxiv Science⌕ Search

bioRxiv · 10.1101/2021.11.13.468472

A live attenuated influenza virus-vectored intranasal COVID-19 vaccine provides rapid, prolonged, and broad protection against SARS-CoV-2 infection

Abstract

Remarkable progress has been made in developing intramuscular vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); however, they are limited with respect to eliciting local immunity in the respiratory tract, which is the primary infection site for SARS-CoV-2. To overcome the limitations of intramuscular vaccines, we constructed a nasal vaccine candidate based on an influenza vector by inserting a gene encoding the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2, named CA4-dNS1-nCoV-RBD (dNS1-RBD). A preclinical study showed that in hamsters challenged 1 day and 7 days after single-dose vaccination or 6 months after booster vaccination, dNS1-RBD largely mitigated lung pathology, with no loss of body weight, caused by either the prototype-like strain or beta variant of SARS-CoV-2. Lasted data showed that the animals could be well protected against beta variant challenge 9 months after vaccination. Notably, the weight loss and lung pathological changes of hamsters could still be significantly reduced when the hamster was vaccinated 24 h after challenge. Moreover, such cellular immunity is relatively unimpaired for the most concerning SARS-CoV-2 variants. The protective immune mechanism of dNS1-RBD could be attributed to the innate immune response in the nasal epithelium, local RBD-specific T cell response in the lung, and RBD-specific IgA and IgG response. Thus, this study demonstrates that the intranasally delivered dNS1-RBD vaccine candidate may offer an important addition to fight against the ongoing COVID-19 pandemic, compensating limitations of current intramuscular vaccines, particularly at the start of an outbreak.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Chen, J., Wang, P., Yuan, L., Zhang, L., Zhao, H., Chen, C., Chen, Y., Han, J., Jia, J., Lu, Z., Hong, J., Chen, L., Fan, C., Wang, Q., Chen, R., Cai, M., Qi, R., Wang, X., Ma, J., Zhou, M., Yu, H., Zhuang, C., Liu, X., Han, Q., Wang, G., Su, Y., Yuan, Q., Cheng, T., Wu, T., Ye, X., Li, C., Zhang, T., Zhang, J., Zhu, H., Chen, H., Xia, N.. 2021-11-15. A live attenuated influenza virus-vectored intranasal COVID-19 vaccine provides rapid, prolonged, and broad protection against SARS-CoV-2 infection. https://doi.org/10.1101/2021.11.13.468472

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Relative expression of THY1 and PDGFRA in equine endometrosis in relation to severity, histopathological features and endometrial transcripts

Equine endometrosis is a degenerative uterine disease characterized by periglandular fibrosis and represents a major cause of subfertility in mares. While stromal cell activation results in pathological tissue remodeling, the involvement of cell-surface integrators (THY1) and growth factor receptors (PDGFRA) was not researched. This study evaluated the relative mRNA expression of THY1 and PDGFRA across Kenney and Doig (KD) endometrosis categories and specific histopathological features. Additionally, transcriptomic correlation profiles between target genes and markers of myofibroblast differentiation (ACTA2), cellular proliferation (MKI67), and steroid hormone receptors (ESR1, PGR) were analyzed. Endometrial samples (n = 47) were quantified using RT-qPCR. Relative mRNA expression of THY1 differed significantly across KD categories (p = 0.014), exhibiting a transient upregulation in category IIA compared with category I (p = 0.009) and category IIB (p = 0.002). Furthermore, THY1 relative mRNA expression was significantly elevated in tissues with glandular basal lamina disruption (p = 0.022). Conversely, PDGFRA relative mRNA expression remained stable across disease categories (p > 0.05). THY1 relative mRNA expression correlated very strongly with ACTA2 ({rho} = 0.875, p < 0.001) and strongly with ESR1 ({rho} = 0.652, p < 0.001). PDGFRA relative mRNA expression exhibited a very strong positive correlation with ESR1 ({rho} = 0.864, p < 0.001) and a strong positive correlation with MKI67 ({rho} = 0.674, p < 0.001). These results indicate that THY1 transcription is transiently induced during early stromal remodeling and basal lamina loss, whereas PDGFRA maintains constitutive transcript stability. Observed co-expression profiles reflect statistical co-variation among stromal remodeling, proliferative, and steroid-responsive cell populations in bulk tissue.

pathology↗

sPLA2 inhibitor-loaded nanoparticles mitigate spontaneous osteoarthritis in guinea pigs

Osteoarthritis (OA) is a prevalent degenerative joint disease lacking effective disease-modifying therapies. Secreted phospholipase A2 (sPLA2), a key upstream regulator of inflammatory lipid mediators, has been implicated in OA pathogenesis, but its therapeutic potential in age-related OA remains unclear. Here, we evaluated the role of sPLA2 and the efficacy of nanoparticle-mediated sPLA2 inhibition in a spontaneous OA model using female Dunkin-Hartley (DH) guinea pigs. We first characterized OA progression and observed age-dependent increases in cartilage degeneration, synovitis, oxidative stress, and sPLA2 expression and enzymatic activity. We then developed sPLA2 inhibitor (thioetheramide-PC)-loaded nanoparticles (sPLA2i-NPs) and demonstrated their superior ability, compared to free inhibitor, to prevent IL-1{beta}-induced cartilage degeneration in guinea pig cartilage explants. In vivo, intra-articular administration of sPLA2i-NPs from 3 months of age significantly attenuated cartilage destruction, synovial inflammation, and osteophyte formation in 7- and 10-month-old guinea pigs. These structural improvements were accompanied by normalization of anabolic and catabolic gene expression and a marked reduction in synovial fluid sPLA2 activity. Importantly, longitudinal gait analysis revealed that sPLA2i-NP treatment preserved limb loading, propulsion, and locomotor performance, demonstrating functional recovery. No systemic toxicity was observed following long-term treatment. Collectively, our findings identify sPLA2 as a key driver of spontaneous OA and establish nanoparticle-mediated sPLA2 inhibition as a promising disease-modifying strategy for age-related OA.

pathology↗

Midlife nonlinearities across scale in Biondi body amyloid formation in the human choroid plexus

Human choroid plexus epithelial cells (CPECs), which produce cerebrospinal fluid and form the blood-cerebrospinal fluid barrier, accumulate discrete intracellular amyloid inclusions called Biondi bodies (BBs). Using systematic manual and machine learning approaches on the choroid plexus glomus, we determined the percentages of CPECs containing thioflavin S-stained BBs as well as BB load and spatial distributions in whole slide images from 77 cases across the human lifespan. On average, BB prevalence was near zero until age 40, rose steeply in the 5th and 6th decades, and exceeded 50% after age 70. As prevalence plateaued, BB load continued to rise with age. Accelerated BB accumulation was seen in two cases of diabetic ketoacidosis, including a 16-year-old, while an 85-year-old with the relatively rare APOE2/E2 genotype had fewer BBs than expected. BB prevalence in the choroid plexus glomus was not associated with Alzheimer's disease, but was lower in females than males. Notably, spatial clustering of BBs was universal across cases while nearest-neighbor analyses suggested cell-to-cell, prion-like BB spread that can account for the nonlinearities seen at tissue and population scales. The abrupt, nonlinear BB accumulation during midlife coincides with or precedes other common aging-associated neuropathologies of the human brain, consistent with broad BB and choroid plexus contributions to brain aging and disease.

pathology↗