〔Abstract〕 To investigate the regulatory effect of overexpressed protein tyrosine phosphatase non-receptor type 2 (Ptpn2) on the inflammatory response of mouse alveolar macrophages (MH-S) induced by SiO₂. Methods Cells with overexpressed Ptpn2 were constructed and induced by SiO₂ . The experimental groups were divided into four groups: the negative control group with an empty vector (NC), the overexpressed Ptpn2 group (P), the negative control group with an empty vector + SiO₂ induction (NS), and the overexpressed Ptpn2 + SiO₂ induction group (PS). Isobaric tags for relative and absolute quantification (iTRAQ) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to screen differential proteins, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) database analyses. Immunofluorescence staining was used to detect the expressions of Tumor necrosis factor (TNF) α, Gasdermin D (GSDMD), and Transforming growth factor (TGF)-β1. Western blot was used to detect the protein expression levels of PTPN2, Toll-like receptor 4 (TLR4), tumor necrosis factor-α (TNF-α), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), and proteins related to the TGF-β1 signaling pathway in the cells of each group. Results iTRAQ results identified 144 differential proteins among the four groups. GO analysis showed that in biological processes (BP), these differential proteins were mainly enriched in IκB kinase/nuclear factor-κB (NF-κB) signaling, cell activation and signal transduction involved in immune responses, and regulation of receptor signaling pathways by signal transducer and activator of transcription (STAT), etc. KEGG analysis revealed that the differential proteins were mainly enriched in Toll- like receptor signaling pathway, NF-κB signaling pathway, NOD-like receptor signaling pathway, TGF-β signaling pathway, and TNF signaling pathway. The results of immunofluorescence staining showed that compared with the NC group, the expressions ofTNF α, GSDMD, and TGF-β1 in the cells ofthe NS group increased; Compared to the NS group, the expression of the aforementioned proteins in the PS group decreased in cellular proteins. The results of Western blot showed that compared with theNC group, the protein expression levels of PTPN2, p-NF-κB、MyD88、TLR4 、 NLRP3、GSDMD、Caspase-1、IL-1β 、 TGF-βR1、 TGF-βR2、p-Smad2/3 intheNS group were significantly upregulated (P < 0.05); Compared with the NS group, the expression levels of the aforementioned proteins in the PS group were significantly downregulated (P < 0.05). Conclusion Overexpression of Ptpn2 can inhibit the protein expressions of TLR4-TNF-α signaling, NLRP3 signaling, and TGF-β1 signaling closely related to inflammatory response in SiO₂-mediated MH-S macrophages.