Background: Large DNA poxviruses encode a diverse family of secreted proteins that
modulate host inflammatory and antiviral responses, in particular by inhibiting one of the key players of
the mammalian immune system, the tumor necrosis factor (TNF).
Methods: We investigated the effects of a recombinant variola (smallpox) virus TNF-decoy receptor
(VARV-CrmB) in a murine model of contact dermatitis. Our results demonstrate that the VARV-CrmB
protein significantly reduces the 2,4-dinitrochlorbenzene (DNCB)-induced migration of skin leukocytes
during the sensitization phase and suppresses ear oedema during the elicitation phase of the contact reaction.
Results: Studies focusing on the bone marrow hematopoiesis in the contact dermatitis model revealed
that the epicutaneous co-application of DNCB and VARV-CrmB protein normalized the DNCBinduced
effects to control levels.
Conclusion: As an effective TNF antagonist, the VARV-CrmB protein might be conceived as a beneficial
candidate for further research and development of therapeutic approaches in the field of the inflammatory