LN, the most severe form of SLE, often surfaces within the first five years following diagnosis and often presents as the initial symptom according to the literature30.The intricate pathogenesis of LN involves genetic, environmental, and hormonal factors that intertwine various inflammatory processes and cellular interactions7. Recently, MPX has garnered attention; however, its replication mechanisms within host cells and genomic characteristics remain underexplored. Recent findings suggest that MPXV infection can disrupt NK cell function, lead to lymphopenia, and facilitate immune evasion, emphasizing the significance of the immune response in combating poxviruses4. To understand and combat its implications, we obtained datasets GSE36854 of MPXV-infected HeLa cells and GSE112943, focusing on patients with LN, from the GEO database. We cross-screened 113 genes with significant differential expression and employed bioinformatic and machine learning approaches to develop a predictive model. Our analysis identified three crucial DE-SRGs, STAT1, ORC2, and GTF2B, for further investigation, given their potential diagnostic value in LN in the context of MPXV.
Cellular senescence, a response to telomere erosion, oxidative stress, and persistent inflammation, leads to permanent growth arrest through the accumulation of cell cycle inhibitors such as p16 INK4a12. Senescent cells exhibit distinct characteristics, including increased β-galactosidase activity and secretion of pro-inflammatory and profibrotic SASP31. In renal senescence and kidney diseases, such as LN, p16 INK4a- or β-galactosidase-positive cells are associated with tissue damage and renal dysfunction12,32. However, the role of cellular senescence in MPXV virus infections remains unknown. In this study, we analyzed the co-expressed genes of LN combined with MPXV virus infection, and functional enrichment and immune infiltration analyses revealed that these genes were involved in cellular senescence “Cellular senescence” “Human T cell leukemia virus l infection” and “Ferroptosis”; BP was enriched in “lymph vessel development”; CC was enriched in cytoplasm; MF is mainly enriched in “protein N-terminal binding” protein N-terminal binding. Analysis of immune cell infiltration showed that the levels of Tr1 and other cells were high, and Th1 was positively correlated with Th17 and NKT. GSEA showed that STAT1, ORC2, and GTF2B genes were mainly enriched in immune-related pathways. In conclusion, DE-SRGs may affect the proportion of immune cells by regulating cellular senescence, which in turn affects disease development.
Our research found that the key genes associated with MPXV infection are involved in regulating the pathogenesis of LN and are mainly enriched in immune-related pathways. Specifically, immune cell subpopulations such as Tr1, Tfh, NKT, MAIT, DC, NK and CD4 + T cells showed higher levels after the body was attacked by MPXV virus, reflecting the active response of the immune system under stress. Further analysis revealed that there is a significant positive correlation between Th1, Th17, and NKT, which supports the imbalance of the immunomodulatory network under the interference of MPXV virus. At the same time, the STAT1, ORC2, and GTF2B genes, as key regulatory factors, were found to be significantly enriched in immune-related pathways such as the T lymphocyte receptor signaling pathway, the B cell receptor signaling pathway, and the Toll-like receptor signaling pathway, highlighting their pivotal role in mediating the immune response and transmitting immune signals. Existing studies have shown that after infection with MPXV virus, immune function is disturbed. MPXV infection can trigger a series of immune responses, including abnormal immune cell function (such as lymphopenia, impaired NK cell function, immune escape, cytokine storm, etc.), changes in blood composition (increased antibodies, increased monocytes and granulocytes), and inhibition of the complement system. These changes are closely related to the occurrence and development of various diseases4.Lupus nephritis, on the other hand, is associated with the deposition of antigen-antibody complexes in kidney tissue. After the MPXV virus invades the body of patients with lupus nephritis, its viral protein can be used as an exogenous antigen to stimulate the body’s immune system to produce specific antibodies and form immune complexes. These complexes are deposited in the glomerular basement membrane of the kidney, thereby activating the complement system, recruiting inflammatory cells, and ultimately triggering the pathological process of LN.
Signal transducer and activator of transcription 1 (STAT1) is a key transcription factor that is important in the immune-inflammatory response and is closely associated with LN and MPXV virus infection33,34,35. Studies have shown that STAT1 is a core gene involved in LN progression. iFN-γ activates the JAK/STAT1 pathway to promote CXCL10 expression, and inhibition of this pathway reduces lupus kidney injury34. In addition, miR-574-5p activates STAT1 signaling by triggering an immune-inflammatory response35. Single-cell sequencing has shown that STAT1 is highly active as an interferon-stimulated gene in some LN patients35. In MPXV virus infection, STAT1 deletion causes up to 100% mortality in mice36, and recombinant MPXV virus vaccine is safe and effective in STAT1 knockout mouse models37. Therefore, STAT1, as a signal transduction and transcription activator, can mediate the activation of intracellular antiviral signaling pathways and regulate the antiviral response of immune cells during MPXV virus infection. In lupus nephritis, abnormally activated STAT1 is involved in regulating the release of local inflammatory cytokines in the kidney and promoting the process of renal fibrosis.
Origin recognition complex 2 (ORC2) is a key protein for the initiation of DNA replication38.Phosphorylation of ORC2 dissociates the replication initiation complex from chromatin and the replication start39.Deletion of ORC2 leads to defective DNA replication40, whereas co-expression of ORC1 and ORC2 prevents apoptosis and facilitates the assembly of ORC on chromatin41. This suggests that ORC2 may influence disease progression by regulating DNA replication and the cell cycle. Although the role of ORC2 in LN and MPXV virus infection is unknown, it has been shown that ORC2 is associated with other diseases. For example, bioinformatics and immunohistochemical analyses have shown that ORC2 can serve as a diagnostic prognostic gene for Barrett’s esophagus and esophageal adenocarcinoma42. In addition, overexpression of ORC2 in a mouse model of myocardial infarction improved cardiac function and reduced fibrosis and immune cell infiltration43. KEGG enrichment analysis in this study showed that LN-related genes were mainly involved in “Cellular senescence”, “Human T-cell leukemia virus infection” and “Fibrosis”. GSEA analysis further showed that ORC2 was mainly enriched in signaling pathways such as Toll-like receptor, cell cycle and T lymphocyte receptor. These results are consistent with the known functions of ORC2 in DNA replication and cell cycle. Therefore, we speculate that ORC2 plays a key role in the regulation of cell cycle initiation. MPXV virus infection may interfere with its normal function, thereby affecting the cell cycle process, and ultimately lead to abnormal immune cell function; ORC2 disorders are closely related to the loss of control of kidney inherent cell proliferation and metabolic disorders of the extracellular matrix.
General transcription factor IIB (GTF2B) is important in the regulation of gene expression, especially in the initiation of RNA polymerase II transcription to assist in the recognition of promoters and complex formation. Research on the function of GTF2B in LN and MPXV virus infection is limited, but it is known to be related to other diseases. Elsby et al. noted that GTF2B is involved in hepatocellular carcinoma proliferation by inhibiting HBV X protein transcriptional activation44 .Cai F et al. found that GTF2B binds to AIP and promotes AIP expression to inhibit GHPA tumor development45. In addition, Zhou W et al. showed that GTF2B regulates apoptosis and invasion in invasive trophoblast cells affecting trophoblast dysfunction in preeclampsia46. Multi-omics studies have shown its involvement in the development of diseases such as heart failure47, osteogenic differentiation of MSCs48, and depression49. In summary, GSEA analysis in this study showed that ORC2 was mainly enriched in signaling pathways such as Toll-like receptor, adhesion junction, Rig I-like receptor and T lymphocyte receptor, which was consistent with the known function of GTF2B, reflecting its transcriptional signaling regulation in disease development.
