Pages
Products

Pseudovirus-Related Service

Overview Pseudovirus-Related Service Contact Us FAQ

Creative Biogene, leveraging cutting-edge virology technology platforms, provides pseudovirus construction and customization services covering various viral families. These services support viral function research, vaccine evaluation, neutralizing antibody detection, and antiviral drug screening. Our pseudovirus technology offers a safe and efficient solution for your research and development work.

Introduction to Pseudovirus

Pseudoviruses are virus-like particles whose surface proteins (such as envelope proteins of enveloped viruses or capsid proteins of non-enveloped viruses) differ from their core components. The target viral proteins on pseudoviruses have structures similar to real viruses and can mediate entry into susceptible cells. Since pseudoviruses do not contain a complete viral genome, they can only complete a single round of infection in susceptible cells.

Advantages of Pseudovirus

Compared to real viruses, pseudovirus-based detection methods offer numerous advantages:

  • Rapid construction: Pseudoviruses can be quickly constructed based on known target protein sequences without using real viruses
  • Biosafety: Most pseudoviruses lack a complete viral genome and cannot replicate continuously, allowing them to be handled in BSL-2 laboratories
  • Convenient quantitative analysis: Most pseudovirus genomes carry reporter genes that enable quantitative analysis through detection of reporter signals after cell infection
  • Structural and functional authenticity: The structure of surface envelope or capsid proteins is similar to real viruses, with nearly identical functionality

In recent years, pseudoviruses have been widely used as alternatives to real viruses for studying viral biological characteristics and evaluating antiviral products. Particularly during the COVID-19 pandemic, SARS-CoV-2 pseudoviruses were extensively utilized globally as important tools for studying this virus. Pseudovirus-based neutralizing antibody detection and antiviral drug screening experiments have become standard methods, replacing high-risk experiments with real viruses.

At Creative Biogene, an industry-leading PV customization service is offered to all of our clients at competitive pricing with rapid turnaround time, ensuring an easy and trouble-free start to your research.

Comprehensive Service System

Antiviral Therapy Development Services

A comprehensive service system is in place to meet the varied research needs across scientific disciplines. Backed by integrated technical capabilities, our solutions are built for reliability and real-world applicability.

Pseudovirus-based high-throughput drug screening and vaccine evaluation

02

Cell model development

Screening virus-sensitive cell lines; establishing stable reporter cell lines (e.g., fluorescence, luciferase)

04

High-throughput evaluation

Automated assays in 96/384-well plates; quantifying infection inhibition via reporter signal (IC50/NT50)

01

Pseudovirus construction

Cloning target viral envelope or epitope genes; constructing compatible pseudovirus vectors (HIV/VSV/MLV); validating expression and infectivity

03

Neutralization assay system

Optimizing MOI and infection conditions; developing standardized pseudovirus infection models for drug/vaccine screening

05

Vaccine efficacy assessment

Detecting serum neutralizing activity post-vaccination; comparing immune responses across different vaccine strategies

Viral Infection Diagnostic Services

Leveraging deep expertise in pseudovirus technology, the diagnostic services offered are tailored to support viral infection studies with a strong focus on result accuracy and reproducibility.

Neutralizing antibody detection and rapid diagnostic reagent development

  • Cloning viral S proteins, N proteins, or other highly immunogenic regions
  • Constructing and expressing purified recombinant antigens (for ELISA, immunochromatography, etc.)

Neutralizing antibody detection platform development

  • Designing colloidal gold/fluorescent/enzyme-linked immunoassays
  • Screening high-affinity monoclonal antibodies for sandwich assay systems
  • Rapid prototype design and performance verification

Sample validation and clinical evaluation

Antigen screening and expression system construction

  • Establishing pseudovirus neutralization detection systems
  • Optimizing serum dilution systems and detection standard curves
  • Evaluating neutralizing antibody titers

Rapid detection reagent development

  • Performing cross-validation using positive/negative clinical samples
  • Evaluating false positive/negative rates and detection limits

Core Technology Platforms

Several complementary technology platforms now underpin our pseudovirus-related services—each shaped by years of technical refinement and designed to work seamlessly together for consistent, high-quality outcomes.

Flexible Multi-Vector Construction Systems

Lentiviral vector systems (HIV/SIV/MLV)

Suitable for enveloped viruses, significantly enhancing pseudovirus titer and stability through optimized Env protein expression and signal peptide design.

VSV vector system

This system supports the construction of replication-deficient and replicative pseudoviruses, suitable for studying viral invasion mechanisms and vaccine development, especially for highly pathogenic viruses.

Self-assembly technology platform

For non-enveloped viruses, mimics natural viral structures by co-expressing capsid proteins (L1/L2) with reporter gene plasmids, ensuring epitope authenticity.

Precise Optimization Strategies

Protein expression enhancement

Improves envelope protein expression efficiency through codon optimization, signal peptide replacement (such as IgGκ signal peptide), and key site mutations.

Cleavage site design

For viruses requiring protease activation (such as influenza virus HA protein), integrates TMPRSS2/HAT co-expression systems to ensure pseudovirus maturation and infection activity.

Targeted modification

Optimizes viral particle assembly efficiency by truncating cytoplasmic tail regions or replacing transmembrane domains.

Service Process

1Requirement analysis: Customizing construction plans based on target virus type (enveloped/non-enveloped) and application scenario (detection/drug screening)

2Gene synthesis and optimization: Full gene synthesis + codon optimization to ensure efficient protein expression

3Pseudovirus packaging: Using three-plasmid/four-plasmid systems (such as HIV vectors) or self-assembly technology, completing packaging within 72 hours

4Titer detection and verification: Quantifying by qPCR/fluorescence reporting systems, conducting parallel live virus neutralization comparison experiments to ensure functional consistency

5Delivery and support: Providing high-titer pseudovirus lyophilized powder and complete experimental protocols, supporting customized reporter genes (Luc/GFP/SEAP)

Contact Us

Choose Creative Biogene for professional, safe, and efficient pseudovirus technology services to help your antiviral research and product development achieve breakthrough progress. For more details about our pseudovirus services or to customize personalized solutions, please contact our technical support team.

FAQ

Q: In constructing self-assembled pseudoviruses for non-enveloped viruses such as HPV or EV71, how can one ensure proper capsid protein folding and efficient reporter gene packaging?

A: For non-enveloped viruses, pseudovirions rely on the self-assembly of capsid proteins (e.g., HPV L1/L2 or EV71 VP1–VP4) with replicons carrying reporter genes. Codon optimization tailored to mammalian systems substantially enhances expression, often boosting titers 5–10 fold. Replicon design is critical-retaining key viral RNA packaging elements like the 5' UTR and IRES enables selective encapsidation. Co-transfection strategies using optimized ratios of capsid and reporter plasmids (e.g., HPV L1:L2: reporter = 2:1:3) help minimize empty particles and increase packaging efficiency, sometimes reaching >70%.

Q: In animal models, how can we address signal attenuation of reporter genes and discrepancies in tissue tropism compared to wild-type viruses?

A: Reporter gene signals in pseudovirus-infected animals typically peak within 5–7 days and may not fully reflect native virus distribution. To overcome this, dual-reporter systems (e.g., luciferase plus fluorescent protein) allow real-time in vivo tracking and precise tissue co-localization. Strong promoters like EF1α or CMV can extend expression duration-CMV-driven luciferase in SARS-CoV-2 pseudovirus models has shown detectable signals up to 14 days post-infection. Moreover, receptor-humanized mouse models (e.g., hACE2 or hDPP-4 transgenics) generated via CRISPR can closely replicate authentic viral entry patterns.

Q: How can pseudoviruses for emerging SARS-CoV-2 variants be constructed rapidly, and how is immune escape evaluated?

A: Rapid response to emerging variants involves an integrated approach combining synthetic biology, high-throughput screening, and structural biology:

  • Synthetic biology: Utilizing public S protein sequences from variants such as Omicron BA.5, pseudovirus constructs can be generated within 48 hours via gene synthesis. In one example, the SARS-CoV-2 D614G pseudovirus was constructed and validated within 72 hours of sequence publication.
  • High-throughput neutralization assays: Using 96-well plate formats, serum samples can be screened against panels of variant pseudoviruses (e.g., Delta, Omicron) with automated plate readers processing thousands of samples per day. This methodology enabled Chinese researchers to evaluate cross-protection conferred by inactivated vaccines.
  • Structure-guided design: Cryo-EM structures of S protein-antibody complexes inform the prediction of escape mutations (e.g., K417N, E484K), allowing for targeted pseudovirus construction to validate their impact. For instance, pseudovirus assays confirmed that the E484K mutation reduces neutralizing activity of certain monoclonal antibodies by over 10-fold.

Q: What are the main barriers in constructing pseudoviruses for flaviviruses like dengue or Zika, and how have recent studies overcome them?

A: The major obstacle lies in the maturation process of envelope protein E, which requires co-expression with prM and host protease (e.g., furin) cleavage within the ER-steps not easily mimicked by standard HIV or VSV vectors, often resulting in titers<10³ IU/mL. Solutions include using chimeric vectors (e.g., Sindbis virus backbones) to facilitate natural secretion pathways or co-expressing furin protease to ensure proper prM-E processing. Additionally, virus-like particles (VLPs) composed of C, prM, and E can structurally mimic native virions without genome packaging and have proven useful in vaccine development.

Quick Inquiry