Fig. 1

Flow cytometry gating strategy used to quantify proportions of B cells and its subpopulations. 75 DLBCL patients with BM (N = 47) and PB (N = 54) samples at diagnosis were subjected to multicolor flow cytometry to look at proportions of B cells and its subpopulations. A plot of forward versus side scatter was used to gate cells falling under the “lymphocytes” region. From the “lymphocyte” gate, B cells were gated as CD19+ and memory B cells were gated as CD19+/CD27+. Following subpopulations were further characterized on the B cell gate, i.e. on the CD19+ gate. Three categories of transitional (trans) B cells were identified as CD10+/CD34-, CD38+/CD21- and CD10+/CD38+ and labelled trans-e, trans-d and trans-a respectively. Precursor (pre-B) cells were gated as CD10+/CD34+ and anergic B cells were gated as CD21(−/low)/CD38-. Specific stains were used to identify the two types of immunoglobulin light chain in B cells, i.e. lambda and kappa populations