March 19, 2025

Researchers in Germany uncover how ASF virus evades pig immune system

Researchers at the Friedrich Loeffler Institute and the University of Greifswald in Germany have gained new insights into how the African swine fever (ASF) virus infiltrates the immune system of infected pigs.

The study was conducted under the experimental direction of Michael R. Knittler and Ulrike Blohm from the FLI Institute of Immunology. ASF is a highly infectious disease that affects domestic and wild pigs, and there is currently no effective vaccine approved in the European Union.

The study, recently published in The Journal of Immunology, focused on pig monocytes, which are specialised immune cells that play a key role in fighting infections. These cells are one of the main targets of the virus. The researchers found that the highly virulent "Armenia2008" strain of the virus (ASFV-A) specifically disrupts antigen presentation on the surface of these monocytes. As a result, infected monocytes can no longer report the presence of the virus to the immune system.

The study revealed that ASFV-A causes stress within the infected monocytes, blocking the intracellular processing of the viral antigen and the production of cellular proteins. This eventually leads to cell death. Dying monocytes release virus-containing cell debris, which can infect neighbouring cells and attract new monocytes. This creates a cycle that accelerates the spread of infection in the animal.

- National Hog Farmer