MIG AND IP-10 - CXC CHEMOKINES THAT TARGET LYMPHOCYTES

Mg and IP-10 are related members of the CXC subfamily of the chemokine family of cytokines. The murine Mig (MuMig), human IP-10, and the mou se homologue of IP-10, Crg-2, were all identified due to the dramatic inductions of their genes in monocytic cells treated with interferon-g amma (IFN-gamma), Studies using recombinant (r) human proteins show th at, unlike most other CXC chemokines, rHuMig and rIP-10 have no activi ty on neutrophils but appear to target lymphocytes specifically, rHuMi g and rIP-10 are active as chemotactic factors for stimulated, but not for resting, T cells, Studies done in vitro and in vivo have shown th at rHuMig and rIP-10 share additional activities, including inhibition of neovascularization, inhibition of hematopoietic progenitor cells, and anti-tumor effects, rHuMig and rIP-10 show reciprocal desensitizat ion on activated T cells and have been demonstrated to share a recepto r, CXCR3, The genes for both MuMig, and Crg-2 are highly expressed in multiple tissues during experimental viral and protozoan infections in mice, but their patterns of expression differ, This suggests that the Migs and IP-10/Crg-2 may play roles in host defense and that, despite their similar activities assayed in vitro, Mig and IP-10/Crg-2 may se rve non-redundant functions in vivo.