For instance, CXCL13, a chemokine C-X-C motif ligand, known to orchestrate cell-cell interactions that regulate lymphocyte infiltration within the tumour microenvironment, was exclusively expressed by all the abovementioned immune cells in the immunoreactive patient and interacted with ACKR4 expressed by CAFs (FB_COMP and FB_COL27A1) and the tumour-associated macrophages (M_MMP9). The gene discussed is MMP9; the disease is neoplasm.