A Single Dose TMV-HA Vaccine Protects Mice from H5N1 Influenza Challenge

Recombinant subunit vaccines are an efficient strategy to meet the demands of a possible influenza pandemic, because of rapid and scalable production. However, vaccines made from recombinant Hemagglutinin (HA) subunit protein are often of low potency, requiring repeated boosting to generate a sustained immune response. Previously, we demonstrated improved immunogenicity of a plant-made H1 Hemagglutinin (HA) vaccine by chemical conjugation to the surface of the Tobacco Mosaic Virus (TMV) which is non infectious in mammals. Antigen coated TMV is taken up by mammalian dendritic cells and is a highly effective antigen carrier for subunit protein vaccines. In this work, we tested the effectiveness of a TMV-H5 HA conjugate vaccine. We compared the TMV-H5 immunogenicity in mice, with and without an oil-in water squalene adjuvant, to H5N1 virus or HA protein alone, as measured by anti-H5 IgG titers and Hemagglutination Inhibition (HAI). We then evaluated the efficacy of the TMV-H5 vaccine by lethal H5N1 virus challenge in mice. Our results show that a single dose of the TMV-H5 conjugate vaccine is sufficient to generate 40% survival, similar to H5 protein given with adjuvant, or 100% survival after vaccination with adjuvant, similar to H5N1 virus vaccination

Transmission experiments support clade-level differences in the transmission and pathogenicity of Cambodian influenza A/H5N1 viruses

Influenza A/H5N1 has circulated in Asia since 2003 and is now enzootic in many countries in that region. In Cambodia, the virus has circulated since 2004 and has intermittently infected humans. During this period, we have noted differences in the rate of infections in humans, potentially associated with the circulation of different viral clades. In particular, a reassortant clade 1.1.2 virus emerged in early 2013 and was associated with a dramatic increase in infections of humans (34 cases) until it was replaced by a clade 2.3.2.1c virus in early 2014. In contrast, only one infection of a human has been reported in the 6 years since the clade 2.3.2.1c virus became the dominant circulating virus. We selected three viruses to represent the main viral clades that have circulated in Cambodia (clade 1.1.2, clade 1.1.2 reassortant, and clade 2.3.2.1c), and we conducted experiments to assess the virulence and transmissibility of these viruses in avian (chicken, duck) and mammalian (ferret) models. Our results suggest that the clade 2.3.2.1c virus is more “avian-like,” with high virulence in both ducks and chickens, but there is no evidence of aerosol transmission of the virus from ducks to ferrets. In contrast, the two clade 1 viruses were less virulent in experimentally infected and contact ducks. However, evidence of chicken-to-ferret aerosol transmission was observed for both clade 1 viruses. The transmission experiments provide insights into clade-level differences that might explain the variation in A/H5N1 infections of humans observed in Cambodia and other settings

mRNA vaccine mitigates SARS-CoV-2 infections and COVID-19

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified in December of 2019 and is responsible for millions of infections and deaths across the globe. Vaccination against SARS-CoV-2 has proven effective to contain the spread of the virus and reduce disease. The production and distribution of these vaccines occurred at a remarkable pace, largely through the employment of the novel mRNA platform. However, interruptions in supply chain and high demand for clinical grade reagents have impeded the manufacture and distribution of mRNA vaccines at a time when accelerated vaccine deployment is crucial. Furthermore, the emergence of SARS-CoV-2 variants across the globe continues to threaten the efficacy of vaccines encoding the ancestral virus spike protein. Here, we report results from preclinical studies on mRNA vaccines developed using a proprietary mRNA production process developed by GreenLight Biosciences. Two mRNA vaccines encoding the full-length, nonstabilized SARS-CoV-2 spike protein, GLB-COV2-042 and GLB-COV2-043, containing uridine and pseudouridine, respectively, were evaluated in rodents for their immunogenicity and protection from SARS-CoV-2 challenge with the ancestral strain and the Alpha (B.1.1.7) and Beta (B.1.351) variants. In mice and hamsters, both vaccines induced robust spike-specific binding and neutralizing antibodies, and in mice, vaccines induced significant T cell responses with a clear Th1 bias. In hamsters, both vaccines conferred significant protection following challenge with SARS-CoV-2 as assessed by weight loss, viral load, and virus replication in the lungs and nasopharynx. These results support the development of GLB-COV2-042 and GLB-COV2-043 for clinical use

Rapid evolution of A(H5N1) influenza viruses after intercontinental spread to North America

Highly pathogenic avian influenza A(H5N1) viruses of clade 2.3.4.4b underwent an explosive geographic expansion in 2021 among wild birds and domestic poultry across Asia, Europe, and Africa. By the end of 2021, 2.3.4.4b viruses were detected in North America, signifying further intercontinental spread. Here we show that the western movement of clade 2.3.4.4b was quickly followed by reassortment with viruses circulating in wild birds in North America, resulting in the acquisition of different combinations of ribonucleoprotein genes. These reassortant A(H5N1) viruses are genotypically and phenotypically diverse, with many causing severe disease with dramatic neurologic involvement in mammals. The proclivity of the current A(H5N1) 2.3.4.4b virus lineage to reassort and target the central nervous system warrants concerted planning to combat the spread and evolution of the virus within the continent and to mitigate the impact of a potential influenza pandemic that could originate from similar A(H5N1) reassortants

Accelerated evolution of SARS-CoV-2 in free-ranging white-tailed deer

The zoonotic origin of the COVID-19 pandemic virus highlights the need to fill the vast gaps in our knowledge of SARS-CoV-2 ecology and evolution in non-human hosts. Here, we detected that SARS-CoV-2 was introduced from humans into white-tailed deer more than 30 times in Ohio, USA during November 2021-March 2022. Subsequently, deer-to-deer transmission persisted for 2–8 months, disseminating across hundreds of kilometers. Newly developed Bayesian phylogenetic methods quantified how SARS-CoV-2 evolution is not only three-times faster in white-tailed deer compared to the rate observed in humans but also driven by different mutational biases and selection pressures. The long-term effect of this accelerated evolutionary rate remains to be seen as no critical phenotypic changes were observed in our animal models using white-tailed deer origin viruses. Still, SARS-CoV-2 has transmitted in white-tailed deer populations for a relatively short duration, and the risk of future changes may have serious consequences for humans and livestock

The IDENTIFY study: the investigation and detection of urological neoplasia in patients referred with suspected urinary tract cancer - a multicentre observational study

Objective To evaluate the contemporary prevalence of urinary tract cancer (bladder cancer, upper tract urothelial cancer [UTUC] and renal cancer) in patients referred to secondary care with haematuria, adjusted for established patient risk markers and geographical variation. Patients and Methods This was an international multicentre prospective observational study. We included patients aged ≥16 years, referred to secondary care with suspected urinary tract cancer. Patients with a known or previous urological malignancy were excluded. We estimated the prevalence of bladder cancer, UTUC, renal cancer and prostate cancer; stratified by age, type of haematuria, sex, and smoking. We used a multivariable mixed-effects logistic regression to adjust cancer prevalence for age, type of haematuria, sex, smoking, hospitals, and countries. Results Of the 11 059 patients assessed for eligibility, 10 896 were included from 110 hospitals across 26 countries. The overall adjusted cancer prevalence (n = 2257) was 28.2% (95% confidence interval [CI] 22.3–34.1), bladder cancer (n = 1951) 24.7% (95% CI 19.1–30.2), UTUC (n = 128) 1.14% (95% CI 0.77–1.52), renal cancer (n = 107) 1.05% (95% CI 0.80–1.29), and prostate cancer (n = 124) 1.75% (95% CI 1.32–2.18). The odds ratios for patient risk markers in the model for all cancers were: age 1.04 (95% CI 1.03–1.05; P < 0.001), visible haematuria 3.47 (95% CI 2.90–4.15; P < 0.001), male sex 1.30 (95% CI 1.14–1.50; P < 0.001), and smoking 2.70 (95% CI 2.30–3.18; P < 0.001). Conclusions A better understanding of cancer prevalence across an international population is required to inform clinical guidelines. We are the first to report urinary tract cancer prevalence across an international population in patients referred to secondary care, adjusted for patient risk markers and geographical variation. Bladder cancer was the most prevalent disease. Visible haematuria was the strongest predictor for urinary tract cancer

Histone Acetyltransferase CBP Is Vital To Demarcate Conventional and Innate CD8+ T-Cell Development▿ †

Defining the chromatin modifications and transcriptional mechanisms that direct the development of different T-cell lineages is a major challenge in immunology. The transcriptional coactivators CREB binding protein (CBP) and the closely related p300, which comprise the KAT3 family of histone/protein lysine acetyltransferases, interact with over 50 T-lymphocyte-essential transcriptional regulators. We show here that CBP, but not p300, modulates the thymic development of conventional adaptive T cells versus those having unconventional innate functions. Conditional inactivation of CBP in the thymus yielded CD8 single-positive (SP) thymocytes with an effector-, memory-, or innate-like T-cell phenotype. In this regard, CD8 SP thymocytes in CBP mutant mice were phenotypically similar to those reported for Itk and Rlk protein tyrosine kinase mutants, including the increased expression of the T-cell master regulatory transcription factor eomesodermin (Eomes) and the interleukin-2 and -15 receptor beta chain (CD122) and an enhanced ability to rapidly produce gamma interferon. CBP was required for the expression of the Itk-dependent genes Egr2, Egr3, and Il2, suggesting that CBP helps mediate Itk-responsive transcription. CBP therefore defines a nuclear component of the signaling pathways that demarcate the development of innate and adaptive naïve CD8+ T cells in the thymus

Virologic differences do not fully explain the diversification of swine influenza viruses in the United States

Influenza A(H1N1) viruses entered the U.S. swine population following the 1918 pandemic and remained genetically stable for roughly 80 years. In 1998, there was an outbreak of influenza-like illness among swine that was caused by A(H3N2) viruses containing the triple reassortant internal gene (TRIG) cassette. Following the TRIG cassette emergence, numerous reassortant viruses were isolated in nature, suggesting that the TRIG virus had an enhanced ability to reassort compared to the classical swine virus. The present study was designed to quantify the relative reassortment capacities of classical and TRIG swine viruses. Reverse genetic viruses were generated from the classical H1N1 virus A/swine/MN/37866/1999 (MN/99), the TRIG virus A/swine/NC/18161/2002 (NC/02), and a seasonal human H3N2 virus, A/TX/6/1996 (TX/96), to measure in vitro reassortment and growth potentials. After coinfection with NC/02 or MN/99 plus TX/96, H1/H3 double-positive cells were identified. Delayed TX/96 infection was fully excluded by both swine viruses. We then analyzed reassortant H3 viruses. Seventy-seven of 81 (95.1%) TX/96-NC/02 reassortants contained at least one polymerase gene segment from NC/02, whereas only 34 of 61 (55.7%) MN/99-TX/96 reassortants contained at least one polymerase gene segment from MN/99. Additionally, 38 of 81 (46.9%) NC/02-TX/96 reassortants contained all NC/02 polymerase gene segments, while none of the MN/99-TX/96 reassortants contained all MN/99 polymerase genes. There were 21 H3 reassortants between MN/99 and TX/96, compared to only 17 H3 reassortants between NC/02 and TX/96. Overall, the results indicate that there are no distinct differences in the ability of the TRIG to reassort with a human virus compared to the classical swine virus. IMPORTANCE There appear to be no differences in the abilities of classical swine and TRIG swine viruses to exclude a second virus, suggesting that under the right circumstances both viruses have similar opportunities to reassort. The increased percentage of TRIG polymerase gene segments in reassortant H3 viruses indicates that these viruses may be more compatible with gene segments from other viruses; however, this needs to be investigated further. Nevertheless, the classical swine virus also showed the ability to reassort, suggesting that factors other than reassortment capacity alone are responsible for the different epidemiologies of TRIG and classical swine viruses. The post-TRIG diversity was likely driven by increased intensive farming practices rather than virologic properties. Our results indicate that host ecology can be a significant factor in viral evolution