Epithelial cell transfection kit, 100 transfections in 96-well plate.
Introduction
The delivery of foreign DNA into eukaryotic cells is one of the most common molecular biology techniques to study biological mechanisms. However, unlike transformed cell lines, the efficient transfection of primary cells can be a problem. EpiFectagen® is a cationic polymer-based transfection system specifically designed and optimized for efficient transfection of primary epithelial cells. Transfection with EpiFectagen® can be carried out in the presence of antibiotics and serum. Instead of normal two-day transfection, an optimized one-day transfection procedure can be performed for time-saving and highly reproducible transfection. 1.5 ml of EpiFectagen® reagent is sufficient for up to 100 transfections per well in 96-well plate.
Storage/Handling
Upon receipt, aliquot and store EpiFectagen reagent A at -20°C, avoid repeated freezing/thawing cycles. Once thawed, store EpiFectagen reagent A at 4°C and use in a month. EpiFectagen reagent B can be kept at 4°C.
Quality Control
Each lot of EpiFectagen is performance tested by transfecting Human Renal Proximal Tubular Epithelial Cells (HRPTEpiCs, Cat. No. 4100, ScienCellT) with Promega® ?SV-bata-Galactosidase control vector. Gene expression is assayed by X-gal staining 24 hours post transfection. Typically, 30-60% transfection efficiency can be achieved (Figure 1).
Procedures for Transfecting Adherent Cells in 96-well Plate*
Preparation of cells
On the day of transfection, coat 96-well plate with poly-l-lysine at 2 µg/cm2. Incubate at 37°C for 2-4 hours. Rinse the poly-l-lysine coated wells with sterile deionized H2O twice before seeding of cells. The pre-coating of poly-l-lysine ensures good and even epithelial cell adhesion.
Select a flask of epithelial cells with 60-80% confluency, harvest and dilute cells in Epithelial Culture Medium to give a final concentration of ~1.1×105 cells/ml.
Transfection complex formation
Prepare plasmid DNA in sterile deionized H2O to give a final concentration of 1 µg/µl. To achieve successful transfection, high quality DNA with OD260/OD 280 of 1.8 or greater is recommended.
For each well, add 0.5 µl plasmid DNA, 10.5 µl sterile deionized H2O and 2 µl EpiFectagen reagent B into a 1.5 ml sterile plastic tube. Vortex gently and spin down briefly. Then add 7 µl EpiFectagen reagent A to make the total volume of the transfection mixture to be 20 µl, vortex for 5 seconds and spin down. Incubate at room temperature for 20-30 min.
Incubation of cells with transfection mixture
Plate 180 µl of cell suspension (~1.1×105 cells/ml) in each well to give ~2×104 cells per well.
Add 20 µl of transfection mixture to each well. Mix by gently rocking the plate side-to-side.
Culture the cells for ~ 24 hours under standard conditions. Or perform a medium change after 4-6 hours' incubation with transfection mixtures, replace with 200 µl fresh culture medium, and culture for additional 16-18 hours. Generally longer incubation time with transfection mixture results in increased transfection efficiency and decreased cell viability.
Harvest cells 24 hours post transfection and assay for gene expression.
* The amounts of cells and various transfection reagents mentioned in the instruction are recommended for performing transfection in 96-well plate. For transfection in larger size wells, the amounts of epithelial cells and transfection reagents (DNA, sterile deionized H2O and EpiFectagen reagents A&B) should be scaled up according to the surface area of the wells (Table 1).
Table 1. Recommended quantities of epithelial cells and EpiFectagen reagents per well
Culture Vessel
Growth Area (cm2/well)
# of cells
1µg/µl DNA stock(µl)
Sterile DI H20(µl)
EpiFectagen® I reagent B (µl)
EpiFectagen® I reagent A (µl)
ECM (µl)
96-well plate
.35
20,000
0.5
10.5
2
7
180
48-well plate
0.8
45,000
1.1
24
4.6
15.9
411
24-well plate
2.0
115,000
2.9
60
11.6
40
1029
12-well plate
4.0
230,000
5.7
120
23
81
2057
6-well plate
9.6
550,000
13.7
288
55
193
4937
Click the picture for large image
Fig 1. HRPTEpiCs expressing ß-galactosidase after transfection using EpiFectagen.