African swine fever (ASF) causes high morbidity and mortality of both domestic pigs and wild boars and severely impacts the swine industry worldwide. ASF virus (ASFV), the etiologic agent of ASF epidemics, mainly infects myeloid cells in swine mononuclear phagocyte system (MPS), including blood-circulating monocytes, tissue-resident macrophages, and dendritic cells (DCs). Since their significant roles in bridging host innate and adaptive immunity, these cells provide ASFV with favorable targets to manipulate and block their antiviral activities, leading to immune escape and immunosuppression. To date, vaccines are still being regarded as the most promising measure to prevent and control ASF outbreaks. However, ASF vaccine development is delayed and limited by existing knowledge gaps in viral immune evasion, pathogenesis, etc. Recent studies have revealed that ASFV can employ diverse strategies to interrupt the host defense mechanisms via abundant self-encoded proteins. Thus, this review mainly focuses on the antagonisms of ASFV-encoded proteins towards IFN-I production, IFN-induced antiviral response, NLRP3 inflammasome activation, and GSDMD-mediated pyroptosis. Additionally, we also make a brief discussion concerning the potential challenges in future development of ASF vaccine.

Porcine reproductive and respiratory syndrome (PRRS) causes significant economic losses to the swine industry. The killed PRRSV vaccine has been reported to be safe and could elicit humoral responses. The killed PRRSV vaccine with a high viral antigen load combined with robust adjuvants could provide good protection against the infection. However, the high virus titer of PRRSV on the successive production cell lines is the prerequisite for this strategy. In this study, we explored PRRSV production in two recombinant Marc-145 cell lines expressing Nsp2 or Nsp4 through a lentivirus system. The results demonstrated that either Nsp2 or Nsp4 expressing Marc-145 cells did not affect cell morphology and growth kinetics but significantly enhanced PRRSV replication. Overall, our exploration may enable the production of high-yield PRRSV and offer a potential tool for developing safer and more effective PRRSV vaccines.

Pseudorabies virus (PRV), an alphaherpesvirus, causes severe neurological and respiratory diseases in multiple mammalian species and poses an emerging threat to public health. Increasing evidence suggests that virus-induced inflammatory cell death plays a pivotal role in shaping host immune responses and disease outcomes. PANoptosis, a newly defined inflammatory programmed cell death pathway integrating pyroptosis, apoptosis, and necroptosis, has been implicated in host defense against diverse pathogens. However, whether PRV infection induces PANoptosis and contributes to inflammatory pathology remains largely unexplored. In this study, we demonstrate that PRV efficiently replicates in Human Acute Monocytic Leukemia Cells (THP-1)-derived macrophages and robustly induces PANoptosis, characterized by the concurrent activation of Gasdermin D, caspase-3, and Mixed Lineage Kinase Domain-Like (MLKL). Pharmacological inhibition of PANoptosis markedly attenuated PRV-induced inflammatory cytokine production in vitro. Furthermore, intranasal inoculation of PRV in Balb/c mice resulted in productive lung infection accompanied by pronounced pulmonary inflammation. Lung tissues from PRV-challenged mice exhibited molecular and histopathological hallmarks of PANoptosis. Importantly, drug-mediated suppression of PANoptosis significantly reduced lung inflammation and inflammatory cytokine expression in vivo. Collectively, our findings identify PANoptosis as a critical mechanism underlying PRV-induced inflammatory responses and suggest that targeting PANoptosis may represent a promising therapeutic strategy for PRV-associated inflammatory diseases.