To evaluate the contribution of the OptiPrep cushion in reducing coisolated contaminants of CCM, we further pelleted the supernatant above the EV-enriched cushion and detected for AIM V pelleted supernatant: 0.70 ± 0.30 and 0.89 ± 0.29 μg/mL CCM for MEC1 and OSU-CLL, respectively; for EV-depleted complete RPMI pelleted supernatant: 0.07 ± 0.03 and 0.10 ± 0.04 μg/mL CCM for MEC1 and OSU-CLL, respectively (Figure 4A). Here, ATR is linked to B-cell chronic lymphocytic leukemia.