Telomeric histone modifications. (A-C) Immunoprecipitations against histone H3 (H3), trimethylated H3K9 (H3K9trim), and acetylated H3K9 (H3K9ac) were performed on chromatin isolated from B cells of 21 CLL patients and 12 healthy donors. An irrelevant IgG instead of specific antibodies was used in the control condition. Slot-blot analyses of telomeric and Alu sequences enrichment were performed using specific probes. Specific enrichment in immunoprecipitated fraction was estimated relatively to the INPUT fraction, and quantified thanks to a total input dilution range. (A,C) Box plots show relative enrichments of telomeric versus Alu sequences (T/A) for different immunoprecipitations. Corresponding Wilcoxon tests P values are inserted in box plots. (A) Comparison of ChIP realized on CLL B cells (CLL) versus normal B cells (Co) and (C) comparison of ChIP results obtained among normal (Co) or CLL (CLL) B cells bearing (TIF⁺) or not (TIF⁻). (B) Representative result of a ChIP experiment performed on B cells from a CLL patient, showing, on the left the input range (IPT) used for the quantification and on the right the dots obtained after deposit of 10% of total H3, H3K9trim and H3K9ac immunoprecipitates. The membrane was revealed using ALU (top) or telomeric probes (bottom).