The MYXV M-T7 Protein

MYXV M-T7 is a secreted 37-kDa glycoprotein with sequence similarity to the interferon y receptor (IFN-yR) that binds to and inhibits the biological activity of 

Infection of rabbits with a MYXV mutant with an inactivated M-T7 gene demonstrated the contribution of M-T7 to MYXV pathogenesis in European rabbits [51]. Marked differences were seen in the size and progression of skin lesions, the onset and severity of secondary bacterial infections and clearance of the virus. M-T7 was implicated in the control of migration of inflammatory cells to sites of infection. However, these results are difficult to interpret because M-T7 targets IFN-y and chemokines, both having relevant roles in inflammatory responses. 

The fact that M-T7 binds not only to IFN-y from rabbit but also to chemokines from various species has allowed its use as a vCKBP in mouse models. The ability of low amounts of recombinant M-T7 protein to attenuate restenosis after balloon angioplasty in rats has been described to be similar to that of the M3 and 35-kDa proteins, as mentioned before. Whether this effect is due to direct inhibition of chemokine activity is not dear at present [25]. Using a rat renal allograft model, chronic rejection was attenuated by M-T7 protein, with significant reduction in tubular and glomerular atrophy, scarring and lymphocyte infiltration [52]. 

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