CHO-K1 Human OPRK1 Cell Line

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

Figure 1. Recombinant OPRK1 CHO-K1 stably expressing OPRK1

The blue peak represents OPRK1 CHO (C22) cells with median FL4-A of 2.17E5; red peak is parental CHO-K1 control (median=779). Clear peak separation verifies high OPRK1 expression, confirming qualified cell line.

Figure 2. HTRF cAMP Assay with OPRK1 CHO-K1

Dynorphin A EC50=0.18 nM, (-)-U-50488 hydrochloride EC50=0.24 nM. Obvious signal response confirms functional OPRK1 receptor activity, the cell line is qualified for GPCR pharmacological 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 OPRK1 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.