CHO-K1 Human CXCR2 β-Arrestin Cell Line

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

Figure 1. Recombinant CXCR2/β-Arrestin/CHO-K1 constitutively expressing CXCR2

The blue curve represents CXCR2 β-Arrestin CHO (C26C16) stained with anti-CXCR2 antibody, with median FL4-A value of 1.30E6. The red curve is parental CHO cells stained with the same antibody as negative control, median FL4-A = 384. The clear shift of fluorescence signal confirms stable CXCR2 expression on the cell membrane.

Figure 2. Dose response of Human IL-8(CXCL8) in CXCR2 β-Arrestin CHO-K1 (C26C16)

The β-arrestin recruitment assay was performed to characterize the functional response of CXCR2 receptor upon stimulation with human IL-8 (CXCL8). The EC50 value is 3.17 ng/ml, demonstrating potent agonist activity of IL-8 and validating the functionality of this CXCR2 β-arrestin reporter cell line.

Figure 3.Inhibition of hlL-8(CXCL8)-induced β-Arrestin Recruitment by IL-8 Neutralization Ab in CXCR2 β-Arrestin CHO-K1(C26C16)

The β-arrestin recruitment assay was used to evaluate the neutralizing effect of IL-8 antibody against hIL-8-triggered CXCR2 activation. The IC50 value is 86.6 ng/ml, which demonstrates that this cell line is suitable for antagonist and neutralizing antibody functional evaluation.

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 CXCR2 β-Arrestin 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.