Analysis of histone acetylation patterns at the cyclin D1 locus and IgH regulatory regions in nonmalignant human B and T cells. (A) Two EBV-immortalized human B-cell lines, LCL1 and LCL2, showed acetylation in all regions except the MTC region. (B) Activated T-cell clone (D160) and cord blood CD4⁺ T cells (T) showed a similar pattern. (C). IgH regulatory regions including Eμ intronic enhancer, 3′ Cα DnaseI-hypersensitive regions HS4 and HS3 from chromosome 14 were acetylated in the normal B/T cells and the MCL cell lines Granta (G) and NCEB-1 (N), but not in the stem cell/erythroleukemia cell line K562 and breast cancer cell line MCF7.