Monkeypox virus (MPXV) can induce systemic skin lesions after infection. This research focused on studying MPXV proliferation and the response of keratinocytes. Using transmission electron microscopy (TEM), we visualized different stages of MPXV development in human immortalized keratinocytes (HaCaT). We identified exocytosis of enveloped viruses as the exit mechanism for MPXV in HaCaT cells. Infected keratinocytes showed submicroscopic changes, such as the formation of vesicle-like structures through the recombination of rough endoplasmic reticulum membranes and alterations in mitochondrial morphology. Transcriptome analysis revealed the suppressed genes related to interferon pathway activation and the reduced expression of antimicrobial peptides and chemokines, which may facilitate viral immune evasion. In addition, pathway enrichment analysis highlighted systemic lupus erythematosus pathway activation and the inhibition of the Toll-like receptor signaling and retinol metabolism pathways, providing insights into the mechanisms underlying MPXV-induced skin lesions. This study advances our understanding of MPXV’s interaction with keratinocytes and the complex mechanisms leading to skin lesions.

Mpox virus (MPXV), a member of the Orthopoxvirus genus in the Poxviridae family, has long been endemic in Africa. The interaction between MPXV infection and peripheral immune responses is of great significance. However, the activation of signaling pathways and molecular changes in peripheral blood mononuclear cells (PBMCs) following MPXV infection remain poorly understood. This study evaluated the transcriptomic profiles of rabbit PBMCs during the mpox acute and recovery phases. The results showed that MPXV infection significantly altered the transcriptomic profiles of PBMCs. At 6 days post-infection, pathways related to pathogenic infection and IL-1 response were enriched, while at 14 days post-infection, the T cell receptor signaling pathway was enriched. During the mpox acute phase, inflammatory cytokines in serum such as IL-1α, IL-1β, IL-8, and IL-21 were upregulated, while MMP-9 and NCAM-1 were downregulated. In rabbits and rhesus monkeys, key genes upregulated in common during the mpox acute period were associated with the interferon pathway (e.g., the ISG15, OAS, and IFIT families), while downregulated genes were related to B-cell activation and differentiation (e.g., the MS4A1 and FCRL families). Additionally, rabbits developed protective immunity against reinfection, with neutralizing antibodies effectively activated. These findings provide insights into the molecular characteristics of PBMCs changes in in vivo models of MPXV infection, and offer references for the diagnosis, vaccine development, and therapeutic research of mpox.