Key result
ASFV infection causes severe lymphopenia in pigs, driven by massive T and B cell depletion.
Why the study?
African swine fever virus causes substantial socioeconomic losses and lacks commercially efficacious vaccines or specific treatments, yet little is known about the swine immune response upon infection.
ASFV infection induces severe lymphopenia through the loss of specific lymphocyte subsets and alters antigen presentation, providing insights into its pathogenesis.
Highlights ASFV immune evasion in pigs; leaves open translation to other hosts or interventions.
Pathogenic African swine fever virus (ASFV) remains a lethal causative agent in the domestic pig industry, which poses a burden on the swine market and causes substantial socioeconomic losses worldwide. Currently, there are no commercially efficacious vaccines or specific treatments available for ASF prevention and control. Unfortunately, little is known about the swine immune response upon ASFV infection. Here, we investigated the host immune response discrepancy induced by the field moderately virulent strain ASFV HB-2208 among healthy, diseased and asymptomatic pigs. In the peripheral blood of diseased swine, lymphopenia is caused by the massive loss of bystander lymphocytes, such as γδ T cells, B cells and CD4+ T cells. Conversely, ASFV has a strong tropism for the mononuclear phagocyte system (MPS) and partial dendritic cells (DCs), whose antigen-presenting ability is impeded by the downregulation of CD80 and MHC I. However, no significant difference in the number of CD8αhigh T cells was detected, whereas the frequencies of NK cells, NKT cells, and regulatory T cells (Tregs) were significantly increased. Additionally, an in vitro model was established with a coculture of primary pulmonary alveolar macrophages (PAMs) and peripheral blood mononuclear cells (PBMCs), which significantly reduced γδ T cells, B cells and CD4+ T cells and increased Tregs. The differentiated immune response might aid in enhancing the understanding of ASFV pathogenesis in suids and provide insights into the mechanism of ASFV-induced lymphopenia for further studies.
No takes yet. Share an insight, caveat, or question.
Xiong et al. (2024) studied African swine fever virus (ASFV) infection (n=29). ASFV HB-2208 infection vs. Healthy ASFV-free pigs and asymptomatic infected pigs was evaluated on Immune cell subpopulation frequencies in peripheral blood. ASFV infection in symptomatic pigs caused severe lymphopenia characterized by a massive loss of γδ T cells, B cells, and CD4+ T cells, alongside an increase in regulatory T cells.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: