Objective: To evaluate the immune function of epitope peptides interacting with porcine PD-1 or PD-L1. Methods: We optimized and synthesized peptides (PD-L14QN-GF and PD-L14QN-AF) using the solid-phase method and assessed their effects on peripheral blood mononuclear cell (PBMC) proliferation and PD-1 and cytokine expression after porcine reproductive and respiratory syndrome virus (PRRSV) infection in vitro and on antibody responses to a porcine circovirus type 2 (PCV2) vaccine in vivo. Results: The optimized peptides PD-L14QN-GF and PD-L14QN-AF exhibited lower binding free energy and higher stability when interacting with the PD-1 target protein.Under both PRRSV-infected and non-infected conditions in vitro, both peptides enhanced the proliferation of PBMCs, inhibited PRRSV RNA replication, and downregulated PD-1 transcription levels. Additionally, PD-L14QN-GF and PD-L14QN-AF upregulated the mRNA transcription and protein secretion of interleukin (IL)-2, IL-10, and interferon-γ to varying degrees. In vivo experiments demonstrated that PD-L14QN-GF significantly increased the antibody titer and seroconversion rate of the PCV2 vaccine. Conclusions and Relevance: PD-L14QN-GF and PD-L14QN-AF induced stronger immune responses than PD-L14. PD-L14QN-GF has potential as an immune-enhancing adjuvant.

The clinic symptoms of cardiac occupying lesions are complex and difficult to diagnose currently. In this study, three cases of atrial angiosarcoma, left ventricular aneurysm and left ventricular diverticulum were selected, respectively. The clinical characteristics, imaging features (echocardiogram, cardiac CT and MRI) and the postoperative and pathological results for patients were studied. We compared the differences in clinical symptoms, morphology, histology and haemodynamics among the three patients. The diagnosis were confirmed by intraoperative and postoperative pathological examination. We conclude that proper imaging approaches would be beneficial to diagnose the cardiac occupying lesions. Accurate preoperative diagnosis is beneficial to preoperative preparation as well as the decrease in operative risks.
Diverticulum ; diagnosis ; Echocardiography ; Heart Aneurysm ; diagnosis ; Heart Ventricles ; pathology ; Hemangiosarcoma ; diagnosis ; Humans ; Magnetic Resonance Imaging ; Tomography, X-Ray Computed