CCL19 and CCL21, which bind to CCR7, are primarily produced by stromal cells and ECs, attracting T cells and facilitating the development of a T-cell zone in TLSs.260,261 In triple-negative breast cancer, the presence of CCL19+ DCs has been linked to TLSs and T cell aggregates. The gene discussed is CCL19; the disease is triple-negative breast carcinoma.