CHO-K1 Human APLNR(APJ) Cell Line

For research use only. Not intended for human or animal clinical trials, therapeutic or diagnostic use.

Figure 1. Recombinant CHO-K1 Human APLNR(APJ) constitutively expressing APLNR

The blue peak represents APLNR(APJ)/CHO-K1 cells with a mean fluorescence intensity (MFI) of 5.71×10⁵. The red peak is the parental CHO-K1 negative control (MFI = 2066). The large shift in fluorescence signal confirms robust surface expression of human APLNR(APJ) receptor on the engineered cell line.

Figure 2. HTRF cAMP Assay With APLNR(APJ) CHO-K1 Cells (C2)

Dose-response curve induced by Apelin-13 shows potent receptor activation with an EC₅₀ value of 0.41 nM, confirming functional APLNR receptor suitable for high-throughput screening and pharmacology studies.

Cell Resuscitation
1)Rapidly thaw the frozen cells in a 37 °C water bath for approximately 60 seconds. Once thawed (which may take slightly less or more than 60 seconds), immediately transfer the cell suspension from the cryovial into a 15 mL centrifuge tube containing 10 mL of pre-warmed CHO-K1 Human APLNR(APJ) Cell Line complete culture medium.
2)Centrifuge cells at 1000 rpm for 5 min to remove medium, then resuspend cells in 5 mL of pre-warmed complete medium.
3)Transfer the cell suspension into a T25 culture flask and incubate at 37 °C with 5% CO₂.
4)After approximately 24–36 hours, replace the medium or passage the cells to remove non-adherent dead cells.

Subculturing procedure
1)When the cell density reaches the appropriate confluency for passaging, wash the cells with PBS, then add 1 mL trypsin to detach the cells. When more than 80% of the cells detach upon gently tapping the culture flask, add complete culture medium to terminate digestion. Gently pipette to obtain a single-cell suspension, transfer to a 15 mL centrifuge tube, and centrifuge at 1000 rpm for 5 minutes.

2)Discard supernatant after centrifugation. Resuspend cells in fresh medium to a single-cell suspension and transfer to a new culture flask for continued growth.

Cell Freezing
After trypsinization and centrifugation of cells from each T75 flask or 10 cm culture dish, discard the supernatant. Add 2 mL of cryopreservation medium (90% FBS + 10% DMSO), gently resuspend thoroughly, and aliquot into two cryovials. Immediately place the cryovials into a controlled-rate freezing container (e.g., Nalgene 5100-0001), fill with isopropanol to the indicated level, and store at −80 °C. After 24 hours, transfer the cryovials to liquid nitrogen for long-term storage.