Lentiviral vectors based on Human Immunodeficiency Virus-1 (HIV-1) are widely used as tools for gene transfer research. These vectors can efficiently integrate exogenous genes or short hairpin RNA (shRNA) into the host cell genome, enabling long-term stable expression of the target sequence. Lentiviral vectors possess distinct advantages, including the ability to infect non-dividing cells, large capacity for exogenous target gene fragments, high stability, and low immunogenicity. Numerous studies have demonstrated that compared to other viral vectors, lentiviruses exhibit higher infection efficiency—they can more easily infect refractory tissues and cells, with an efficiency typically ranging from 30% to over 95%. In terms of infectivity, lentiviral vectors can effectively transduce a variety of cell types, such as neurons, hepatocytes, cardiomyocytes, tumor cells, endothelial cells, and stem cells. For hard-to-transfect cells (e.g., primary cells, stem cells, and undifferentiated cells), lentiviral vectors significantly improve the transduction efficiency of target genes or shRNA. Additionally, they increase the likelihood of integrating the target gene/shRNA into the host cell genome, facilitating convenient and rapid long-term stable expression of the target sequence. Lentiviral vectors have become one of the most commonly used carriers for expressing exogenous genes or shRNA in both in vitro and in vivo studies, and their applications are expanding increasingly.
However, the restricted uptake of viral particles often reduces the success rate of gene or shRNA expression. This forces researchers to use higher-titer viral particles to achieve optimal gene expression efficiency. Nevertheless, increasing viral dosage to enhance expression may cause toxic side effects in many cell types and incur unnecessary high costs.
To address this challenge, Aladdin has developed a unique Viral Transfection Enhancer—a lentiviral transduction enhancer specifically designed to improve lentiviral gene transduction efficiency. As a highly efficient, non-cytotoxic chemical enhancer for lentiviral transduction, it is a non-ionic, receptor-independent surfactant. By interacting with the cell membrane, it reduces membrane viscosity, enhances lipid exchange and transmembrane transport, and promotes the fusion of lentiviruses with the cell membrane—ultimately boosting viral transduction efficiency. Notably, the transduction enhancement mediated by Viral Transfection Enhancer is independent of specific cell surface receptors. During the transduction process, it avoids cell membrane depolarization and damage, thus not affecting cell viability. Research has confirmed that Viral Transfection Enhancer improves lentiviral transduction efficiency in mouse T cells, mouse hematopoietic stem cells (HSCs), and human HSCs without compromising the survival, proliferation, or differentiation ability of transduced cells.
As a universally acting (receptor-independent) adjuvant, Viral Transfection Enhancer is broadly applicable to various hard-to-transduce cell types, including CD34+ hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs), neural stem cells, primary T cells, natural killer (NK) cells, and fibroblasts. It is also effective for refractory mouse T cells.
Product Features:
⁕ Ready-to-use reagent, no need for reagent preparation, simple and convenient.
⁕ Sterile preparation, can be directly added to cells for use.
⁕ Can enhance lentiviral transduction efficiency by up to 90%, facilitating the achievement of ideal gene expression efficiency.
⁕ Avoids depolarization and damage of cell membranes during transduction, without affecting the survival, proliferation, or differentiation ability of transduced cells.
Experimental Procedures:
1. Package the lentivirus and determine its titer. Calculate the amount of virus required for target cell infection based on the virus titer and MOI (Multiplicity of Infection).
2. One day before the experiment: Digest the target cells in good growth state, count them, and dilute to a concentration of 1–3×10⁵ cells/mL. Seed the cells into a 24-well plate at a volume of 500 μL per well (corresponding to 0.5–1.5×10⁵ cells per well). Incubate the plate in a 37°C, 5% CO₂ incubator. Ensure that the cell confluency reaches approximately 30%–50% on the day of viral infection.
⁕ Suspension cells do not need to be seeded one day in advance. On the day of the experiment, count and seed the cells, then directly add the virus mixture.
3. Prepare the lentivirus + Viral Transfection Enhancer + medium mixture. The recommended dilution ratio for Viral Transfection Enhancer is 1:500 to 1:100.
⁕ Compared with the cytotoxicity caused by polybrene addition, Viral Transfection Enhancer exhibits extremely low cytotoxicity and causes almost no damage to cell growth. Therefore, for cells that cannot tolerate polybrene, Viral Transfection Enhancer is the preferred viral infection enhancer.
4. Aspirate the medium from the target cells in the 24-well plate, add the lentivirus mixture prepared in Step 3, and return the plate to the 37°C, 5% CO₂ incubator for continued culture.
⁕ For infecting suspension cells or semi-suspension cells, use the flat-angle centrifugation transfection method: Add an appropriate amount of virus solution to the cell culture plate, seal the plate tightly, place it in a flat-angle centrifuge, centrifuge at 800×g for 30 minutes (centrifugation parameters may vary by cell type), then transfer the plate to the incubator for continued culture.
5. Sixteen hours after viral infection, replace the medium with fresh medium and continue culturing.
6. Forty-eight hours after viral infection: Either add selection medium to screen for stable cell lines, or detect the expression of the target gene using methods such as fluorescence microscopy, flow cytometry, Western blot, or qPCR (quantitative Polymerase Chain Reaction).
Scope of Application:
As a universally acting (receptor-independent) adjuvant, Viral Transfection Enhancer can be widely applied to various hard-to-transduce cell types. It significantly improves lentiviral transduction efficiency without affecting the survival, proliferation, or differentiation ability of transduced cells.
Precautions:
1. Compared with the cytotoxicity caused by adding polybrene, Viral Transfection Enhancer has extremely low toxicity to cells and causes almost no damage to cell growth. Therefore, for cells that cannot use polybrene, Viral Transfection Enhancer is the preferred viral infection enhancer.
2. For your health and safety, please operate in a standardized manner and wear a lab coat and gloves when conducting experiments.
3. All lentivirus-related operations must be performed in a Biosafety Level 2 (BSL2) biological safety cabinet.
4. This product is for research use only and shall not be used for clinical diagnosis or treatment.
