Figure 3. Regulatory B-cell subsets in Colorectal Cancer.

(A) The percentage of CD24^highCD38^high (transitional) B cells is lower in tumor samples (n=28) than in peripheral blood of CRC patients (n=44) or healthy controls (n=10) (1.2% vs. 3.5%/2,3%, p<0,005/p<0,05 respectively). (B) Whereas transitional B cells are very rare in early stage CRC the frequency increases in advanced stage disease (n=28) (0.7% of B cells in Stage I+II vs. 1.8% in Stage III+IV, p<0,05). (C) CD24^highCD27⁺ B cells make up a high percentage of tumor associated B cells in tumor samples (n=28) and PBMC of colorectal cancer (n=44) and are significantly elevated compared to PBMC of healthy controls (n=10) (21.1%/18.5% vs. 11.3%, p<0,05). (D) Exemplary density plot showing CD24^highCD27⁺ B cells in a tumor sample from a patient with colorectal cancer (gated on lymphocytic FSC/SSC,CD45⁺,CD19⁺,CD20⁺).