GSM8118801: memory CD4, nasal polyps, ATAC, patient2; Homo sapiens; ATAC-seq
Freshly obtained nasal polyps were immediately minced and incubated in RPMI 1640 medium containing 1 mg/ml collagenase, 0.5 mg/ml hyaluronidase, and 0.2 mg/ml DNase I (Sigma-Aldrich). After incubation, nasal polyp mononuclear cells were purified by density gradient centrifugation using Percoll solution (GE Healthcare). PBMCs were isolated from peripheral blood using Ficoll-Paque Plus solution (GE Healthcare). 5×10^4 cells were pelleted, washed with 50 μl 1× PBS, and lysed with 50 μl lysis buffer. The nuclei were re-suspended in a 40 μl transposition reaction with 2 μl Tn5 transposase (Illumina) to tag and fragment the accessible chromatin at 37 °C for 30 min. Fragmented DNAs were purified using the QIAGEN MiniElute PCR Purification Kit and amplified using 8-10 PCR cycles based on the amplification curve. The libraries were sequenced on an Illumina NextSeq 500 and NovaSeq 6000 Sequencing System.