We provide standardized, traceable viral packaging services, covering mainstream research areas such as oncology, neuroscience, and microbiology, with extensive packaging experience across multiple systems.
When you need to stably deliver a gene of interest (an overexpression/knockdown/knockout element) into cells or a living animal, with long-term expression or in vivo application required, viral packaging is a step you can’t avoid — it answers the core question of "how do you actually get a designed genetic element into the target cells."
| Feature | Lentivirus | Adenovirus | AAV |
|---|---|---|---|
| Genome type | Single-stranded RNA (retrovirus) | Double-stranded DNA (non-enveloped) | Single-stranded DNA (non-enveloped) |
| Genome integration | Integrates into the host genome | Non-integrating, episomal expression (transient) | Non-integrating, mainly episomal expression |
| Theoretical packaging capacity | About 10 kb (limit of the viral genomic RNA itself) | First-generation (E1/E3-deleted) about 8 kb; helper-dependent (gutless) up to 36 kb | About 4.7 kb (wild-type genome size including ITRs) |
| Recommended packaging capacity | Within about 8 kb (including regulatory elements); titer drops noticeably beyond this | First-generation: within about 7.5 kb | Within about 4.4 kb (transgene insert excluding ITRs); titer drops sharply once total length exceeds about 4.9 kb |
| Typical titer range (after concentration) | 10⁷–10⁹ TU/mL | 10¹⁰–10¹² VP/mL | 10¹²–10¹³ GC/mL |
| Immunogenicity | Lower | Higher | Lower |
| Typical applications | Stable cell line construction, long-term in vitro expression, cell therapy vectors | Efficient transient expression in vitro and in vivo, vaccine vectors | Long-term in vivo expression, neuroscience, gene therapy |
| Dimension | siRNA | Plasmid (Transient Transfection) | Lentivirus | Adenovirus | AAV |
|---|---|---|---|---|---|
| Nature/Composition | Chemically synthesized or in-vitro-transcribed double-stranded RNA molecule (~21-23nt) | Double-stranded circular DNA molecule | Genus Lentivirus, family Retroviridae; single-stranded RNA genome, enveloped | Family Adenoviridae; double-stranded linear DNA genome, non-enveloped | Family Parvoviridae; single-stranded DNA genome, non-enveloped, replication-dependent on a helper virus |
| Max Insert Length | No "gene of interest" concept — itself ~21-23bp, targeting an mRNA fragment | Large, up to 10-20kb+ (depending on the backbone) | About 8kb (limited by total transfer-plasmid length) | About 7-8kb (first-generation); helper-dependent up to 36kb | Very small, about 4.7kb (strictly limited, often requiring splitting or a compact Cas protein) |
| Typical Insert Length Range | Fixed at 21-23nt, gene length is not a consideration | Typically 0.5-8kb (excluding the vector backbone) | Typically kept within 6kb for better titer and expression efficiency | Typically 5-7kb (first-generation); helper-dependent still generally recommended within 30kb | Typically within 4.4kb (total length including ITRs not exceeding 4.7-4.9kb) |
| Transfection Reagent Needed | Yes (lipid-based transfection reagent or electroporation) | Yes (lipid-based, polymer-based, or electroporation) | No (the virus directly infects the cell) | No (the virus directly infects the cell) | No (the virus directly infects the cell) |
| Genome Integration | Non-integrating | Usually non-integrating (episomal expression) | Integrating (reverse-transcribed to DNA and integrated into the host genome) | Non-integrating, exists episomally in the nucleus | Usually non-integrating, persists long-term episomally |
| Onset Time | Fast — knockdown effect observable 24-48 hours after transfection | Fast — expression begins 24-48 hours after transfection | Slower — expression begins 48-72 hours after infection; stable expression requires about 1 week to establish the line | Fast — high expression within 24 hours of infection | Moderately slow — typically peaks at 1-4 weeks (especially notable in vivo) |
| Duration of Expression/Silencing | Brief, typically 3-7 days, rapidly diluted by cell division | Mainly transient, expression declines after about 3-7 days | Long-term and stable — once integrated, expression persists through cell division | Transient, typically 1-2 weeks, rapidly diluted by cell division | Long-term (can persist months to years in non-dividing cells; gradually diluted by division in dividing cells) |
| Immunogenicity | Lower, though double-stranded RNA can activate innate immunity (interferon pathway) | Lower | Moderate — third-generation self-inactivating (SIN) systems have greatly reduced this | Higher (strongly immunogenic capsid proteins; prone to clearance or inflammatory response in vivo) | Low (the lowest among current viral systems, suitable for repeated/long-term in vivo use) |
| Applicable Cell Types | Diluted faster by division in dividing cells; relatively more stable but still transient in non-dividing cells | Diluted quickly in dividing cells; difficult to efficiently transfect primary/suspension cells | Can infect both dividing and non-dividing cells (a core advantage over retrovirus) | Can infect both dividing and non-dividing cells; expression is relatively stable in non-dividing cells | Especially suited to long-term expression in non-dividing cells (neurons, cardiomyocytes, hepatocytes) |
| In Vitro/In Vivo Suitability | Mainly in vitro; in vivo use requires chemical modification or an LNP-type delivery system | Mainly in vitro; in vivo use requires special delivery (hydrodynamic injection, electroporation, etc.) | Suitable both in vitro and in vivo; a common tool for stable genetic modification | Suitable both in vitro and in vivo; commonly used in vivo for high transient expression | Mainly aimed at long-term in vivo application; relatively lower in vitro transduction efficiency |
| Biosafety Level | BSL-1 (no viral risk) | BSL-1 | BSL-2 | BSL-2 | BSL-1 (some helper-virus procedures follow BSL-2) |
| Preparation/Packaging Time | Fast — chemical synthesis typically takes a few days | Fast — plasmid extraction takes 1-2 days | Moderate — packaging + concentration + titer testing takes about 1-2 weeks | Moderate — about 1-2 weeks | Longer — about 2-3 weeks (a more complex purification process) |
| Relative Cost | Low | Low | Moderately high | Moderate | Higher |
| Main Applications | Rapid initial screening of gene function, transient knockdown verification | Transient overexpression/knockdown verification, reporter gene experiments | Stable cell line construction, long-term gene function research, long-term in vivo gene delivery | Efficient transient expression, rapid in vivo gene delivery, vaccine vector development | Long-term in vivo gene therapy research, neural circuit tracing and manipulation, tissue-specific long-term expression |
| Key Advantages | Simple, fast, no viral handling, low cost | Simple, low cost, no viral biosafety concerns | Long-term stable expression, can infect non-dividing cells, moderate capacity | High infection efficiency, high expression, larger capacity (especially helper-dependent) | Lowest immunogenicity, best safety, strong long-term expression in non-dividing cells |
| Main Limitations | Short-lived effect, off-target effects, lower in vivo delivery efficiency | Transfection efficiency varies greatly by cell type, transient expression | Risk of insertional mutagenesis from integration (reduced by SIN systems), longer preparation time, requires BSL-2 | High immunogenicity (limits repeat dosing), non-integrating so expression is transient | Smallest capacity (4.7kb), relatively lower in vitro transduction efficiency, slower onset, higher cost |
Chemically synthesized or in-vitro-transcribed double-stranded RNA of about 21-23nt, which is loaded into the RISC complex after transfection and recognizes and degrades the target mRNA through base complementarity, achieving transient silencing of gene expression.
Circular double-stranded DNA is introduced into cells via liposomes, polymers, or electroporation, where it is transiently expressed episomally in the nucleus without integrating into the genome; expression is gradually diluted by cell division.
A vector engineered from HIV and other lentiviruses. After infecting a cell, its RNA genome is reverse-transcribed into DNA and integrated into the host chromosome, achieving long-term stable expression and infecting both dividing and non-dividing cells.
A double-stranded DNA virus with high infection efficiency and high titer; its genome exists mainly episomally in the nucleus without integrating, making it well suited to fast, efficient transient expression in vitro and in vivo.
A single-stranded DNA virus that depends on a helper virus (such as adenovirus) for replication. It has low immunogenicity and good safety, persisting mainly as an episome — especially well suited to long-term in vivo expression in non-dividing cells such as neurons.
Titer, purity, and sterility testing documented throughout, with a test report delivered
All three viral systems have clear delivery windows; special projects discussed in advance
Mature packaging experience across mainstream areas including oncology, neuroscience, and microbiology
Local technical support in one channel, from design through troubleshooting
Submit your experimental plan and objectives
Technical advisor confirms the protocol and timeline
Pay a deposit of at least 50% of the project cost to enter production
Quality control documented throughout production
Settle the balance and complete acceptance
Standard, custom, and large orders all require a deposit of at least 50% of the contract value to begin. The timing for the remaining balance is agreed separately for each project.
Please complete acceptance within 1 month of receiving the product or report. Any concerns about the deliverable should be raised within this window; we will respond within 2 business days.