Tumor samples revealed a higher percentage of activated B cells (characterized by expression of CD19, CD20 and CD86) than PBMCs of CRC patients (16.8% vs. 4.1%, p <0,005, Fig. 1B) or healthy controls (16,8% vs. 4,5%, p<0,005, Fig. 1B). Here, CD19 is linked to colorectal carcinoma.