The monoclonal antibody 6D4 recognizes human C-X-C motif chemokine 10 (IP-10), a protein of 98 amino acids. IP-10, also known as CXCL10, functions as ligand for the CXCR3 receptor. IP-10 belongs to the α-chemokine (C-X-C) family, which can be divided in two subfamilies: (1) potent chemoattractants for neutrophils, like IL-8 and (2) potent chemoattractants for lymphocytes, like the IFNɣ inducible protein (IP)-10. IP-10 is produced by a wide variety of cell types ranging from neutrophils, dendritic cells and monocytes to hepatocytes, endothelial cells and keratinocytes. The cytokine is reported to be involved in a scala of inflammatory pathologies such as HIV, encephalitis, cutaneous T cell lymphoma, chronic hepatitis, psoriasis and acute anterior uveitis. Various observations strongly suggest a role for the C-X-C chemokines IL-8 and IP-10 in the regulation of angiogenic activity in cancer and in idiopathic pulmonary fibrosis. Furthermore IP-10 is associated with acute rejection processes estimated by the predictive properties of urinary IP-10 expression for the short- and long-term graft function after kidney transplantation.