We propose a model where an effective response to ICI is marked with CXCL13+ CD8 T cell-driven recruitment of highly diversified, CXCR5+ B cell clones whose subsequent (tumor) antigen presentation activities induce and sustain the activation of tumor-reactive CD4 Tfh and CD8 T cells (Figure 5D). The gene discussed is CXCR5; the disease is neoplasm.