The chicken interferon system
We study the interferon (IFN) system in the context of influenza viral infections. Our previous results indicated that the interferon-regulated chicken Mx protein, unlike the mammalian counterparts, does not mediate resistance to influenza virus. We further found that type I IFN is unable to protect chickens from disease induced by highly pathogenic avian influenza viruses (see figure). Preliminary data indicate that chicken IFN-λ might exhibit enhanced antiviral activity under certain in vivo conditions.
IFN treatment failed to block transmission of R65 during cohousing with infected birds.
(A) Experimental setup. Uninfected birds were treated by the intravenous route with a total of 10^7 units of chicken IFN-alpha or with a control protein at 8 and 2 h prior to exposure to seeder birds and once more at 12 h after first exposure to seeder birds. Twelve hours before cohousing, the seeders were infected with a lethal dose of R65-wt (10^6 PFU per bird) so that they shed infectious virus when grouped together with the uninfected birds.
(B) Plasma IFN levels in treated birds. Fifteen minutes after the second treatment of the birds with either IFN or control protein, blood was drawn from each animal and plasma IFN levels were measured using a bioassay. Each dot represents the value from one individual bird.
(C) Survival curves of IFN-treated (n=8) and control-treated (n=8) birds. (Figure from Penski et al. 2011)
Open questions presently being investigated include:
a) Role of IFN-λ for antiviral defence of chickens
b) Cell types contributing to synthesis of type I IFN in organs of virus-infected chickens
Selected Publications from our group
- Reuter, A., Soubies, S., Hartle, S., Schusser, B., Kaspers, B., Staeheli, P., Rubbenstroth, D. Antiviral activity of lambda interferon in chickens. J. Virol. 88: 2835-2843 (2014)
- Penski N, Kothlow S, Krohmann C, Ruggli N, Schusser B, Gohrbandt S, Hundt J, Veits J, Breithaupt A, Kochs G, Stech J, Summerfield A, Vahlenkamp T, Kaspers B, Staeheli P. The NS1 protein of avian influenza viruses suppresses interferon synthesis in mice but not in chickens. J. Virol. 85: 7730-7741 (2011)
- Schusser B, Reuter A, von der Malsburg A, Penski N, Weigend S, Kaspers B, Staeheli P, Haertle S. Mx is dispensable for interferon-mediated resistance of chicken 1 cells against influenza A virus. J. Virol. 85: 8307-8315 (2011)
Collaboration
Dr. Sonja Härtle and Prof. Bernd Kaspers, LMU Munich
Head:
Prof. Dr. med. Hartmut Hengel
hartmut.hengel@uniklinik-freiburg.de