African swine fever (ASF) is a notifiable and one of the most complexed and devastating infectious disease of pigs, wild boar and other representatives of Suidae family. African swine fever virus (ASFV) developed different molecular mechanisms to evade host immune response including alteration of interferon production by multigene family protein (MGF505-2R), inhibion of NF-κB and nuclear activating factor in T-cells by the A238L protein, or modulation of host defense by CD2v lectin-like protein encoded by EP402R and EP153R genes. The current situation in regards to ASF in Poland seems to be stable in comparison to other eastern European countries but until the date in total 87 ASF cases in wild boar and 3 outbreaks in pigs were identified. The previous studies showed that ASFV isolates circulating on common territory may vary in genes related to evading host immune defense. The presented study aimed to perform analysis of nucleotide sequences related to inhibition or modulation of infected host response among 67 field ASF isolates collected from wild boar and pigs. The nucleotide and amino acid sequence derived from the analyzed A238L and EP153R regions showed 100% identity. However, minor but remarkable genetic diversity was found within EP402R and MGF505-2R genes suggesting slow molecular evolution of circulating ASFV isolates and important role of this gene in modulation of interferon I production and hemadsorption phenomenon. The obtained nucleotide sequences of Polish ASFV isolates were closely related to Georgia 2007/1 and Odintsovo 02/14 isolates suggesting their common Caucasian origin. Further study are still in progress in order to reveal genetic diversity of ASFV isolates within DP71L, A179L, MGF360-1L and 173R-1329R intragenic regions to show the complete variability of ASFV isolates.
Funded by KNOW Scientific Consortium "Healthy Animal - Safe Food", decision of Ministry of Science and Higher Education No. 05-1/KNOW2/2015 (K/01/1.1)