TABLE 1.

Virus elution from CHO-CAR and CHO-DAF cellsa

Virus statusMean % (±SD) of virus for:
CHO-CAR cellsCHO-DAF cells
Eluted at 37°C25 (±2)5 (±1)
Released from cell pellet by detergent68 (±2)48 (±6)
Retained in cell pellet after detergent3 (±0.3)36 (±9)
  • a CHO-CAR and CHO-DAF cells (2.5 × 106) were incubated with 35S-labeled CB3-RD overnight at 4°C and then washed to remove unbound virus and resuspended in 150 μl of Dulbecco's phosphate-buffered saline (dPBS). CB3-RD bound to CHO-CAR cells at 4,581 cpm and to CHO-DAF cells at 11,834 cpm. Cells were incubated for 30 min at 37°C and then were pelleted for 2 min at 1,000 rpm (Eppendorf F45-24-11 microcentrifuge rotor), and supernatants containing eluted virus were collected. Cell pellets were lysed with detergent solution (PBS containing 1% Triton X-100, 0.5% deoxycholate, 0.1% SDS) for 10 min on ice; lysates were centrifuged for 2 min at 13,000 rpm, and then the radioactivity released or retained in the cell pellet was determined. Results are expressed as percentages of the total bound virus for triplicate samples. Approximately 10% of the bound virus was not recovered.