IVD of Influenza B Virus

Influenza B Virus

Influenza B virus is an RNA virus that causes seasonal influenza and mainly infects humans and a few mammals. After infection, patients will develop symptoms such as high fever, cough, and breathing, as well as severe cases may be accompanied by heart and kidney failure. Compared with the influenza A virus, the symptoms, testing, and treatment are similar, but the severe disease and fatality rates are lower. Due to the characteristics of high sensitivity, specificity, and short time consumption, molecular biology diagnostic technology has become an indispensable method in the in vitro diagnosis (IVD) of influenza B virus.

.Figure 1. Influenza B proteins, their function, and antiviral targets. (Zaraket H, et al., 2021)

Main Steps of IVD for Influenza B Virus

  • Virus culture. Virus detection by cytopathic effect, hemagglutinin assay, or fluorescent antibody staining.
  • Viral antigen testing. The patient's nasopharyngeal secretions were collected for viral antigen detection. If the test result is positive, it indicates that the patient is infected with the influenza B virus.
  • Viral nucleic acid detection. Samples such as nasal swabs, throat swabs, nasopharyngeal swabs, tracheal extracts, or sputum from patients are collected for PCR, RT-PCR, and LAMP.
  • Microarray chip technology.

Creative BioMart provides high-quality recombinant influenza B protein used for IVD, including ELISA, lateral flow assays, western blots, and other immunoassays.

Highlights of Our Products

  • High sensitivity, high specificity, and high purity.
  • It is widely used and suitable for downstream immunological experiments.
  • Easy to store and transport, conducive to large-scale production and use of vaccines.
  • Outstanding success rate and fast development speed.

Our Outstanding Advantages

  • IVD proteins can be used to test for a variety of diseases and conditions, making them valuable tools for diagnosing and monitoring health.
  • Guarantee high performance, high reliability, and high consistency of protein quality, leading the industry.
  • A complete IVD protein platform can provide customized services to meet different scientific research needs.
  • High-quality service, high-level experiments, and reliable analysis.

Applications of Influenza B Virus Protein

1. Vaccine Development:

Hemagglutinin (HA): This surface glycoprotein is critical for virus attachment to host cells and is a primary target for vaccine development. Vaccines aim to elicit an immune response against the HA protein to prevent infection.

Neuraminidase (NA): Another surface protein that helps in the release of new viral particles from host cells. Inhibitors of NA are used as antiviral treatments.

2. Diagnostic Tools:

Nucleoprotein (NP): This protein is highly conserved and can be used in diagnostic assays, like ELISA and PCR, to detect the presence of the influenza B virus in clinical samples.

Matrix Proteins (M1 and M2): These proteins are also employed in diagnostic assays. The M2 protein, for example, has been targeted in immunoassays to detect viral presence.

3. Antiviral Drug Development:

Neuraminidase (NA): As mentioned, NA is targeted by antiviral drugs. Research on mutations in the NA protein can inform the development of novel inhibitors that are effective against resistant strains.

Polymerase Complex Proteins (PA, PB1, and PB2): These proteins are involved in viral RNA replication. Understanding their structure and function can aid in developing drugs that inhibit viral replication.

4. Basic Research:

Non-structural Proteins (NS1 and NS2): These proteins help the virus evade the host immune response and are key to understanding influenza B virus pathology. NS1, in particular, interrupts host immune signaling pathways.

Study of Viral Evolution and Mutation: The relatively conserved nature of some influenza B proteins, in contrast with the highly variable HA and NA, makes them useful for phylogenetic studies and understanding viral evolution.

5. Monoclonal Antibody Development:

Hemagglutinin (HA) and Neuraminidase (NA): These proteins are used to generate monoclonal antibodies that can neutralize the virus. Such antibodies can be used both as therapeutic agents and as tools in research to study viral entry and egress.

6. Immune Response Studies:

Nucleoprotein (NP) and Matrix Proteins (M1 and M2): These internal proteins are commonly used to study T-cell responses, providing insight into how the immune system targets the influenza B virus during infection.

Case Study

Case 1: Carlock MA, Ross TM. A computationally optimized broadly reactive hemagglutinin vaccine elicits neutralizing antibodies against influenza B viruses from both lineages. Sci Rep. 2023 Sep 23;13(1):15911. doi: 10.1038/s41598-023-43003-2. PMID: 37741893; PMCID: PMC10517972.

Influenza B viruses (IBV) can cause severe disease and death much like influenza A viruses (IAV), with a disproportionate number of infections in children. To develop more effective influenza B virus vaccines, three novel IBV hemagglutinin (HA) vaccines were designed using a computationally optimized broadly reactive antigen (COBRA) methodology. Conversely, VLPs expressing wild-type IBV HA antigens preferentially boosted titers against viruses from the same lineage and there was little-to-no seroprotective antibodies detected in ferrets with mismatched IBV pre-immune infections.

Fig2. HAI serum antibody titers induced by wild-type B/YAM vaccinations. Immunologically naive ferrets were infected with a B/YAM virus, SH/02 (top), or with a B/VIC virus, HK/01 (bottom) and then vaccinated once 90 days later. Serum was collected at day 90 following preimmunization (Pre-Vax) and day 120 (Post-Vax). HAI titers were assessed against five B/YAM viruses (yellow) and five B/VIC viruses (purple). Values are the log2 HAI titers of each individual ferret (n = 4) from antisera collected at the two timepoints. Dotted lines indicate a 1:40 to 1:80 HAI titer range. Statistical analyses were performed using unpaired parametric t tests to determine significance of vaccine-induced antibodies: p > 0.05 = ns, p ≤ 0.05 = *, p ≤ 0.01 = **, p ≤ 0.001 = ***, p ≤ 0.0001 = ****.

Case 2: Rowe T, Davis W, Wentworth DE, Ross T. Differential interferon responses to influenza A and B viruses in primary ferret respiratory epithelial cells. J Virol. 2024 Feb 20;98(2):e0149423. doi: 10.1128/jvi.01494-23. Epub 2024 Jan 31. PMID: 38294251; PMCID: PMC10878268.

Influenza B viruses (IBV) cocirculate with influenza A viruses (IAV) and cause periodic epidemics of disease, yet antibody and cellular responses following IBV infection are less well understood. Using the ferret model for antisera generation for influenza surveillance purposes, IAV resulted in robust antibody responses following infection, whereas IBV required an additional booster dose, over 85% of the time, to generate equivalent antibody titers. In this study, the authors utilized primary differentiated ferret nasal epithelial cells (FNECs) which were inoculated with IAV and IBV to study differences in innate immune responses which may result in differences in adaptive immune responses in the host.

Fig3. Heatmap of early/late gene expression in IAV/IBV-infected FNEC. Influenza A and B infected (33°C, MOI = 0.3) FNEC from four independent experiments performed in triplicate. Average fold gene expression, compared to uninfected FNEC, blue = downregulated and red = upregulated. (A) Comparison of IAV: CA and KS, H1N1PDM09 and H3N2, respectively; IBV: BR and PH, B-Victoria and B-Yamagata lineages, respectively. Temporal RNA expression from 12 to 72 h postinfection. All gene groups (Table 1) are separated by dotted lines or solid lines for IFN. (B) Average gene expression comparison of all IAV "A" to all IBV "B" infected FNEC by type followed by an hour postinfection. IFN gene regulation demarcated between dotted lines. Up to two outliers were removed using statistical analysis (Grubb's test) from 12 replicates/gene from four independent experiments if necessary.

Reference

  • Zaraket H, Hurt A C, Clinch B, et al. (2021). Burden of influenza B virus infection and considerations for clinical management[J]. Antiviral Research. 185: 104970.