Genetically modified pigs with CD163 point mutation are resistant to HP-PRRSV infection.

Porcine reproductive and respiratory syndrome (PRRS) is a globally prevalent contagious disease caused by the positive-strand RNA PRRS virus (PRRSV), resulting in substantial economic losses in the swine industry. Modifying the CD163 SRCR5 domain, either through deletion or substitution, can eff1ectively confer resistance to PRRSV infection in pigs. However, large fragment modifications in pigs inevitably raise concerns about potential adverse effects on growth performance. Reducing the impact of genetic modifications on normal physiological functions is a promising direction for developing PRRSV-resistant pigs. In the current study, we identified a specific functional amino acid in CD163 that influences PRRSV proliferation. Viral infection experiments conducted on Marc145 and PK-15 CD163 cells illustrated that the mE535G or corresponding pE529G mutations markedly inhibited highly pathogenic PRRSV (HP-PRRSV) proliferation by preventing viral binding and entry. Furthermore, individual viral challenge tests revealed that pigs with the E529G mutation had viral loads two orders of magnitude lower than wild-type (WT) pigs, confirming effective resistance to HP-PRRSV. Examination of the physiological indicators and scavenger function of CD163 verified no significant differences between the WT and E529G pigs. These findings suggest that E529G pigs can be used for breeding PRRSV-resistant pigs, providing novel insights into controlling future PRRSV outbreaks.

The CXCLs-CXCR2 axis modulates the cross-communication between tumor-associated neutrophils and tumor cells in cervical cancer.

OBJECTIVE: This study aimed to check the expression profile of the C-X-C motif chemokine ligands (CXCLs)-C-X-C motif chemokine receptor 2 (CXCR2) axis in cervical cancer and to explore the cross-talk between cervical cancer cells and neutrophils via CXCLs-CXCR2 axis. METHODS: Available RNA-sequencing data based on bulk tissues and single-cell/nucleus RNA-sequencing data were used for bioinformatic analysis. Cervical cancer cell lines Hela and SiHa cells were utilized for in vitro and in vivo studies. RESULTS: Except for neutrophils, CXCR2 mRNA expression is limited in other types of cells in the cervical tumor microenvironment. CXCLs bind to CXCR2 and are mainly expressed by tumor cells. CXCL1, 2, 3, 5, 6, and 8, which are consistently associated with neutrophil infiltration, are also linked to poor prognosis. SB225002 (a CXCR2 inhibitor) treatment significantly impairs SiHa cell-induced neutrophil migration. CXCL1, CXCL2, CXCL5, or CXCL8 neutralized conditioned medium from SiHa cells have weaker recruiting effects. The conditioned medium of neutrophils from healthy donors can slow cancer cell proliferation. Conditioned medium of tumor-associated neutrophils (TANs) can drastically enhance cervical cancer cell growth in vitro and in vivo. CONCLUSIONS: The CXCLs-CXCR2 axis is critical in neutrophil recruitment and tumor cell proliferation in the cervical cancer microenvironment.