Properties of the recombinant TNF-binding proteins from variola, monkeypox, and cowpox viruses are different.

Tumor necrosis factor (TNF), a potent proinflammatory and antiviral cytokine, is a critical extracellular immune regulator targeted by poxviruses through the activity of virus-encoded family of TNF-binding proteins (CrmB, CrmC, CrmD, and CrmE). The only TNF-binding protein from variola virus (VARV), the causative agent of smallpox, infecting exclusively humans, is CrmB. Here we have aligned the amino acid sequences of CrmB proteins from 10 VARV, 14 cowpox virus (CPXV), and 22 monkeypox virus (MPXV) strains.