CIITA and hepatocellular carcinoma: The PAX5 activity, which was investigated in immune-enriched or CAF-enriched regions only, co-localizes with spots showing high expression of the genes CD19, CD22, CD79A, and CIITA (B cell markers) (Fig. 3D), relative to spots corresponding to HCC or CAF clusters confirming that this is an essential factor for B cell lineage activation and maturation.