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

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.

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A safe and highly efficacious measles virus-based vaccine expressing SARS-CoV-2 stabilized prefusion spike

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2026153118 ◽

2021 ◽

Vol 118 (12) ◽

pp. e2026153118

Author(s):

Mijia Lu ◽

Piyush Dravid ◽

Yuexiu Zhang ◽

Sheetal Trivedi ◽

Anzhong Li ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Measles Virus ◽

Vaccine Candidate ◽

Body Weight Loss ◽

Neutralizing Antibody ◽

T Cell Response ◽

Lung Pathology ◽

S Protein ◽

Efficacious Vaccine ◽

Further Development

The current pandemic of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) highlights an urgent need to develop a safe, efficacious, and durable vaccine. Using a measles virus (rMeV) vaccine strain as the backbone, we developed a series of recombinant attenuated vaccine candidates expressing various forms of the SARS-CoV-2 spike (S) protein and its receptor binding domain (RBD) and evaluated their efficacy in cotton rat, IFNAR−/−mice, IFNAR−/−-hCD46 mice, and golden Syrian hamsters. We found that rMeV expressing stabilized prefusion S protein (rMeV-preS) was more potent in inducing SARS-CoV-2–specific neutralizing antibodies than rMeV expressing full-length S protein (rMeV-S), while the rMeVs expressing different lengths of RBD (rMeV-RBD) were the least potent. Animals immunized with rMeV-preS produced higher levels of neutralizing antibody than found in convalescent sera from COVID-19 patients and a strong Th1-biased T cell response. The rMeV-preS also provided complete protection of hamsters from challenge with SARS-CoV-2, preventing replication in lungs and nasal turbinates, body weight loss, cytokine storm, and lung pathology. These data demonstrate that rMeV-preS is a safe and highly efficacious vaccine candidate, supporting its further development as a SARS-CoV-2 vaccine.

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Human Monoclonal Antibody Cocktail for the Treatment or Prophylaxis of Middle East Respiratory Syndrome Coronavirus

The Journal of Infectious Diseases ◽

10.1093/infdis/jiab036 ◽

2021 ◽

Author(s):

Sumathi Sivapalasingam ◽

George A Saviolakis ◽

Kirsten Kulcsar ◽

Aya Nakamura ◽

Thomas Conrad ◽

...

Keyword(s):

Middle East ◽

Adverse Events ◽

Phase 1 ◽

Human Monoclonal Antibody ◽

Preclinical Study ◽

Middle East Respiratory Syndrome ◽

Lung Pathology ◽

Phase 1 Study ◽

Serious Adverse Events ◽

Dipeptidyl Peptidase 4

Abstract Background REGN3048 and REGN3051 are human monoclonal antibodies (mAb) targeting the spike glycoprotein on the Middle East respiratory syndrome coronavirus (MERS-CoV), which binds to the receptor dipeptidyl peptidase-4 (DPP4) and is necessary for infection of susceptible cells. Methods Preclinical study: REGN3048, REGN3051 and isotype immunoglobulin G (IgG) were administered to humanized DPP4 (huDPP4) mice 1 day prior to and 1 day after infection with MERS-CoV (Jordan strain). Virus titers and lung pathology were assessed. Phase 1 study: healthy adults received the combined mAb (n = 36) or placebo (n = 12) and followed for 121 days. Six dose levels were studied. Strict safety criteria were met prior to dose escalation. Results Preclinical study: REGN3048 plus REGN3051, prophylactically or therapeutically, was substantially more effective for reducing viral titer, lung inflammation, and pathology in huDPP4 mice compared with control antibodies and to each antibody monotherapy. Phase 1 study: REGN3048 plus REGN3051 was well tolerated with no dose-limiting adverse events, deaths, serious adverse events, or infusion reactions. Each mAb displayed pharmacokinetics expected of human IgG1 antibodies; it was not immunogenic. Conclusions REGN3048 and REGN3051 in combination were well tolerated. The clinical and preclinical data support further development for the treatment or prophylaxis of MERS-CoV infection.

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Mucosal Influenza Vector Vaccine Carrying TB10.4 and HspX Antigens Provides Protection against Mycobacterium tuberculosis in Mice and Guinea Pigs

Vaccines ◽

10.3390/vaccines9040394 ◽

2021 ◽

Vol 9 (4) ◽

pp. 394

Author(s):

Mariia Sergeeva ◽

Ekaterina Romanovskaya-Romanko ◽

Natalia Zabolotnyh ◽

Anastasia Pulkina ◽

Kirill Vasilyev ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Vaccine Candidate ◽

Cell Immune Response ◽

Lung Pathology ◽

Ns1 Protein ◽

Reading Frame ◽

Intranasal Immunization ◽

Vector Vaccine ◽

Boost Immunization ◽

New Strategies

New strategies providing protection against tuberculosis (TB) are still pending. The airborne nature of Mycobacterium tuberculosis (M.tb) infection assumes that the mucosal delivery of the TB vaccine could be a more promising strategy than the systemic route of immunization. We developed a mucosal TB vaccine candidate based on recombinant attenuated influenza vector (Flu/THSP) co-expressing truncated NS1 protein NS1(1–124) and a full-length TB10.4 and HspX proteins of M.tb within an NS1 protein open reading frame. The Flu/THSP vector was safe and stimulated a systemic TB-specific CD4+ and CD8+ T-cell immune response after intranasal immunization in mice. Double intranasal immunization with the Flu/THSP vector induced protection against two virulent M.tb strains equal to the effect of BCG subcutaneous injection in mice. In a guinea pig TB model, one intranasal immunization with Flu/THSP improved protection against M.tb when tested as a vaccine candidate for boosting BCG-primed immunity. Importantly, enhanced protection provided by a heterologous BCG-prime → Flu/THSP vector boost immunization scheme was associated with a significantly reduced lung and spleen bacterial burden (mean decrease of 0.77 lg CFU and 0.72 lg CFU, respectively) and improved lung pathology 8.5 weeks post-infection with virulent M.tb strain H37Rv.

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Moraxella catarrhalis Bacterium without Endotoxin, a Potential Vaccine Candidate

Infection and Immunity ◽

10.1128/iai.73.11.7569-7577.2005 ◽

2005 ◽

Vol 73 (11) ◽

pp. 7569-7577 ◽

Cited By ~ 68

Author(s):

Daxin Peng ◽

Wenzhou Hong ◽

Biswa P. Choudhury ◽

Russell W. Carlson ◽

Xin-Xing Gu

Keyword(s):

Moraxella Catarrhalis ◽

Lipid A ◽

Vaccine Candidate ◽

Gene Encoding ◽

Potential Vaccine Candidate ◽

Whole Cells ◽

Potential Vaccine ◽

Major Surface ◽

Membrane Components ◽

Human Infections

ABSTRACT Lipooligosaccharide (LOS) is a major surface component of Moraxella catarrhalis and a possible virulence factor in the pathogenesis of human infections caused by this organism. The presence of LOS on the bacterium is an obstacle to the development of vaccines derived from whole cells or outer membrane components of the bacterium. An lpxA gene encoding UDP-N-acetylglucosamine acyltransferase responsible for the first step of lipid A biosynthesis was identified by the construction and characterization of an isogenic M. catarrhalis lpxA mutant in strain O35E. The resulting mutant was viable despite the complete loss of LOS. The mutant strain showed significantly decreased toxicity by the Limulus amebocyte lysate assay, reduced resistance to normal human serum, reduced adherence to human epithelial cells, and enhanced clearance in lungs and nasopharynx in a mouse aerosol challenge model. Importantly, the mutant elicited high levels of antibodies with bactericidal activity and provided protection against a challenge with the wild-type strain. These data suggest that the null LOS mutant is attenuated and may be a potential vaccine candidate against M. catarrhalis.

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Development of a novel Live Attenuated Influenza A Virus vaccine encoding the IgA-inducing protein

10.20944/preprints202106.0180.v1 ◽

2021 ◽

Author(s):

C. Joaquín Cáceres ◽

Stivalis Cardenas-Garcia ◽

Aarti Jain ◽

L. Claire Gay ◽

Silvia Carnaccini ◽

...

Keyword(s):

Influenza A ◽

Protein Microarray ◽

Natural Infection ◽

Vaccine Safety ◽

Gene Encoding ◽

Lethal Challenge ◽

Homologous Virus ◽

Genes Encoding ◽

Live Attenuated Influenza Virus ◽

Better Than

Live attenuated influenza virus (LAIV) vaccines elicit a combination of systemic and mucosal immunity by mimicking a natural infection. To further enhance protective mucosal responses, we incorporated the gene encoding the IgA-inducing protein (IGIP) into the LAIV genomes of the cold-adapted A/Leningrad/134/17/57 (H2N2) strain (caLen) and the experimental attenuated backbone A/turkey/Ohio/313053/04 (H3N2) (OH/04att). Incorporation of IGIP into the caLen background led to a virus that grew poorly in prototypical substrates. In contrast, IGIP in the OH/04att background (IGIP-H1att) virus grew to titers comparable to the isogenic backbone H1att (H1N1) without IGIP. IGIP-H1att- and H1caLen-vaccinated mice were protected against lethal challenge with a homologous virus. The IGIP-H1att vaccine generated robust serum HAI responses in naïve mice against the homologous virus, equal or better than those obtained with the H1caLen vaccine. Analyses of IgG and IgA responses using a protein microarray revealed qualitative differences in humoral and mucosal responses between vaccine groups. Overall, serum and bronchoalveolar lavage samples from the IGIP-H1att group showed trends towards increased stimulation of IgG and IgA responses compared to H1caLen samples. In summary, introduction of genes encoding immunomodulatory functions into a candidate LAIV that can serve as natural adjuvants to improve overall vaccine safety and efficacy.

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Enhancement of Immune Responses by an AttenuatedSalmonella entericaSerovar Typhimurium Strain Secreting anEscherichia coliHeat-Labile Enterotoxin B Subunit Protein as an Adjuvant for a LiveSalmonellaVaccine Candidate

Clinical and Vaccine Immunology ◽

10.1128/cvi.00407-10 ◽

2010 ◽

Vol 18 (2) ◽

pp. 203-209 ◽

Cited By ~ 32

Author(s):

Jin Hur ◽

John Hwa Lee

Keyword(s):

Immune Responses ◽

Vaccine Candidate ◽

Clinical Signs ◽

Secretory Iga ◽

Enzyme Linked Immunosorbent Assay ◽

Gene Encoding ◽

Typhimurium Strain ◽

Immunization Strategies ◽

Serovar Typhimurium ◽

Group B

ABSTRACTA plasmid harboringeltB, the gene encoding heat-labile enterotoxin (LTB), was constructed by insertion ofeltBinto an Asd+β-lactamase signal plasmid (pMMP65). This was introduced into the ΔlonΔcpxRΔasd Salmonella entericaserovar Typhimurium strain and designated the LTB adjuvant strain. LTB protein production and secretion from the strain were demonstrated with an immunoblot assay and enzyme-linked immunosorbent assay. The LTB strain was evaluated for enhancement of immunity and protection efficacy induced by a previously constructed liveSalmonellavaccine candidate. In addition, immunization strategies using the LTB strain were optimized for effective salmonellosis protection. Seventy female BALB/c mice were divided into seven groups (A to G;n= 10 mice per group). Mice were primed at 6 weeks of age and boosted at 9 weeks of age. All mice were orally challenged with a virulent wild-type strain at week 3 postbooster. Serum IgG and IgA titers from mice immunized with the LTB strain alone or with a mixture of the LTB strain and the vaccine candidate were significantly increased. The secretory IgA titers from mice immunized with the LTB strain alone or with the mixture were at least 2.2 times greater than those of control mice. In addition, all group E mice (primed with the vaccine-LTB mixture and boosted with the vaccine candidate) were free of clinical signs of salmonellosis and survived a virulent challenge. In contrast, death due to the challenge was 100% in control mice, 80% in group A mice (single immunization with the vaccine candidate), 60% in group B mice (primed and boosted with the vaccine candidate), 40% in group C mice (single immunization with the LTB strain), 30% in group D mice (primed and boosted with the LTB strain), and 30% in group F mice (primed and boosted with the vaccine-LTB mixture). These results suggest that vaccination with the LTB strain, especially when added at the prime stage only, effectively enhances immune responses and protection against salmonellosis.

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A Candida albicans Mannoprotein Deprived of Its Mannan Moiety Is Efficiently Taken Up and Processed by Human Dendritic Cells and Induces T-Cell Activation without Stimulating Proinflammatory Cytokine Production

Infection and Immunity ◽

10.1128/iai.00669-08 ◽

2008 ◽

Vol 76 (9) ◽

pp. 4359-4367 ◽

Cited By ~ 21

Author(s):

Donatella Pietrella ◽

Patrizia Lupo ◽

Anna Rachini ◽

Silvia Sandini ◽

Alessandra Ciervo ◽

...

Keyword(s):

Dendritic Cells ◽

Candida Albicans ◽

T Cell ◽

T Cell Activation ◽

Cell Activation ◽

Vaccine Candidate ◽

Pathogenic Fungi ◽

T Cell Response ◽

Necrosis Factor Alpha ◽

Recombinant Product

ABSTRACT Mannoproteins are cell wall components of pathogenic fungi and play major virulence and immunogenic roles with both their mannan and protein moieties. The 65-kDa mannoprotein (MP65) of Candida albicans is a β-glucanase adhesin recognized as a major target of the human immune response against this fungus, and its recombinant product (rMP65; devoid of the mannan moiety) is presently under consideration as a vaccine candidate. Here we investigated cellular and molecular aspects of the interaction of rMP65 with human antigen-presenting cells. We also assessed the ability of rMP65 to initiate a T-cell response. Both the native mannosylated MP65 (nMP65) and the recombinant product were efficiently bound and taken up by macrophages and dendritic cells. However, contrarily to nMP65, rMP65 did not induce tumor necrosis factor alpha and interleukin-6 release from these cells. On the other hand, rMP65 was rapidly endocytosed by both macrophages and dendritic cells, in a process involving both clathrin-dependent and clathrin-independent mechanisms. Moreover, the RGD sequence inhibited rMP65 uptake to some extent. After internalization, rMP65 partially colocalized with lysosomal membrane-associated glycoproteins 1 and 2. This possibly resulted in efficient protein degradation and presentation to CD4+ T cells, which proliferated and produced gamma interferon. Collectively, these results demonstrate that the absence of the mannan moiety does not deprive MP65 of the capacity to initiate the pattern of cellular and molecular events leading to antigen presentation and T-cell activation, which are essential features for further consideration of MP65 as a potential vaccine candidate.

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Variation in gene encoding the co-inhibitory molecule BTLA is associated with survival in patients treated for clear cell renal carcinoma – results of a prospective cohort study

Archives of Medical Science ◽

10.5114/aoms/142407 ◽

2021 ◽

Author(s):

Krzysztof Tupikowski ◽

Anna Partyka ◽

Edyta Pawlak ◽

Kuba Ptaszkowski ◽

Romuald Zdrojowy ◽

...

Keyword(s):

Renal Cell Carcinoma ◽

Overall Survival ◽

Cell Carcinoma ◽

Renal Cell ◽

Clear Cell ◽

T Cell Response ◽

Disease Stage ◽

Tumor Diameter ◽

Gene Encoding ◽

Cell Renal Cell Carcinoma

IntroductionThe successful introduction of immune checkpoint blockade approaches to renal-cell carcinoma (RCC) treatment indicates the importance of molecules regulating the T cell response to RCC risk and progression.Material and methodsIn this study, we evaluate the association of variations in the CTLA-4, BTLA and CD28 genes with overall survival (OS) of RCC patients and specifically clear cell RCC (ccRCC) patients. The following previously genotyped using RFLP method or TaqManSNP Genotyping Assays single nucleotide polymorphisms (SNPs) were analyzed: CTLA-4 gene: c.49A>G (rs231775), g.319C>T (rs5742909), g.*6230G>A (CT60; rs3087243), g.*10223G>T (Jo31; rs11571302); CD28 gene: c.17+3T>C (rs3116496), c.-1042G>A (rs3181098); BTLA gene: rs2705511, rs1982809, rs9288952, rs9288953, rs2705535 and rs1844089.ResultsDuring long term observation (6.5 years) we discovered that possessing of A allele at BTLA rs1844089 SNP, together with advanced disease (stage >3, tumor grade >3, tumor diameter ≥70mm), is an independent risk factor of death which increases the HR (hazard ratio) of death by more than two-fold (HR=2.21, 95%CI 1.28-3.83). Furthermore, the OS of patients bearing this allele is 6 months shorter than for homozygous [GG] patients (42.5 vs. 48.2 months).ConclusionsOur results indicate for the first time that genetic variation within the gene encoding the BTLA is significantly associated with overall survival in clear cell renal cell carcinoma patients.

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Preclinical characterization of immunogenicity and efficacy against diarrhea from MecVax, a multivalent enterotoxigenic E. coli vaccine candidate

Infection and Immunity ◽

10.1128/iai.00106-21 ◽

2021 ◽

Author(s):

Hyesuk Seo ◽

Carolina Garcia ◽

Xiaosai Ruan ◽

Qiangde Duan ◽

David A Sack ◽

...

Keyword(s):

Escherichia Coli ◽

Developing Countries ◽

Vaccine Development ◽

Vaccine Candidate ◽

Preclinical Study ◽

Watery Diarrhea ◽

E Coli ◽

Heat Stable ◽

Protective Antibodies

There are no vaccines licensed for enterotoxigenic Escherichia coli (ETEC), a leading cause of diarrhea for children in developing countries and international travelers. Virulence heterogeneity among strains and difficulties identifying safe antigens for protective antibodies against STa, a potent but poorly immunogenic heat-stable toxin which plays a key role in ETEC diarrhea, are challenges in ETEC vaccine development. To overcome these challenges, we applied toxoid fusion strategy and novel epitope- and structure-based multiepitope-fusion-antigen (MEFA) vaccinology platform to construct two chimeric multivalent proteins, toxoid fusion 3xSTaN12S-mnLTR192G/L211A and adhesin CFA/I/II/IV MEFA, and demonstrated that proteins induced protective antibodies against STa and heat-labile toxin (LT) produced by all ETEC strains or the seven most important ETEC adhesins (CFA/I, CS1 to CS6) expressed by the ETEC strains causing 60-70% diarrheal cases and moderate-to-severe cases. Combining two proteins, we prepared a protein-based multivalent ETEC vaccine, MecVax. MecVax was broadly immunogenic; mice and pigs intramuscularly immunized with MecVax developed no apparent adverse effects but robust antibody responses to the target toxins and adhesins. Importantly, MecVax-induced antibodies were broadly protective, demonstrated by significant adherence inhibition against E. coli bacteria producing any of the seven adhesins and neutralization of STa and CT enterotoxicity. Moreover, MecVax protected against watery diarrhea, and over 70% or 90% any diarrhea from an STa+ or an LT+ ETEC strain in a pig challenge model. These results indicated that MecVax induces broadly protective antibodies and prevents diarrhea preclinically, signifying MecVax potentially an effective injectable vaccine for ETEC. IMPORTANCE: Enterotoxigenic Escherichia coli (ETEC) bacteria are a top cause of children’s diarrhea and travelers’ diarrhea and are responsible for over 220 million diarrheal cases and more than 100,000 deaths annually. A safe and effective ETEC vaccine can significantly improve public health, particularly in developing countries. Data from this preclinical study showed that MecVax induces broadly protective anti-adhesin and antitoxin antibodies, becoming the first ETEC vaccine candidate to induce protective antibodies inhibiting adherence of the seven most important ETEC adhesins and neutralizing enterotoxicity of LT but also STa toxin. More importantly, MecVax is shown to protect against clinical diarrhea from STa+ or LT+ ETEC infection in a pig challenge model, recording protection from antibodies induced by protein-based injectable subunit vaccine MecVax against ETEC diarrhea and perhaps the possibility of IM administered protein vaccines for protection against intestinal mucosal infection.

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LRRK2 Phosphorylation: Behind the Scenes

The Neuroscientist ◽

10.1177/1073858418756309 ◽

2018 ◽

Vol 24 (5) ◽

pp. 486-500 ◽

Cited By ~ 10

Author(s):

Tina De Wit ◽

Veerle Baekelandt ◽

Evy Lobbestael

Keyword(s):

Cultured Cells ◽

Kinase Domain ◽

Lung Pathology ◽

Gene Encoding ◽

Kinase Inhibition ◽

Knock Out ◽

Downstream Signaling ◽

Protein Protein Interaction ◽

Pathogenic Variants ◽

Lrrk2 Kinase

Mutations in the gene encoding leucine-rich repeat kinase 2 (LRRK2) are known today as the most common genetic cause of Parkinson’s disease (PD). LRRK2 is a large protein that is hypothesized to regulate other proteins as a scaffold in downstream signaling pathways. This is supported by the multiple domain composition of LRRK2 with several protein-protein interaction domains combined with kinase and GTPase activity. LRRK2 is highly phosphorylated at sites that are strictly controlled by upstream regulators, including its own kinase domain. In cultured cells, most pathogenic mutants display increased autophosphorylation at S1292, but decreased phosphorylation at sites controlled by other kinases. We only begin to understand how LRRK2 phosphorylation is regulated and how this impacts its physiological and pathological function. Intriguingly, LRRK2 kinase inhibition, currently one of the most prevailing disease-modifying therapeutic strategies for PD, induces LRRK2 dephosphorylation at sites that are also dephosphorylated in pathogenic variants. In addition, LRRK2 kinase inhibition can induce LRRK2 protein degradation, which might be related to the observed inhibitor-induced adverse effects on the lung in rodents and non-human primates, as it resembles the lung pathology in LRRK2 knock-out animals. In this review, we will provide an overview of how LRRK2 phosphorylation is regulated and how this complex regulation relates to several molecular and cellular features of LRRK2.

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