During E. coli mastitis, MECs lining alveoli and ducts were shown by in situ hybridization to produce CXCL8 mRNA (152), converging with the in vitro production of CXCL8 by MECs in response to E. coli LPS (135) to establish that MECs are a major source of CXCL8 during E. coli mastitis. The gene discussed is CXCL8; the disease is mastitis.