To　explore　the　pyroptosis　of　macrophage　cells　induced　by　PM2.5　exposure,　in　this　study,　THP-1　cells　were　used　as　human　macrophage　cell　model　to　investigate　PM2.5-induced　pyroptosis.　THP-1　cells　were　exposed　to　different　comcentration　of　PM2.5,　the　viability　of　THP-1　cells　was　detected　using　a　Cell　Counting　Kit-8　assay.　Lactate　dehydrogenase　（LDH）　in　the　culture　medium　of　THP-1　cells　were　measured　using　a　colorimetric　assay.　In　the　THP-1　cells,　the　levels　of　IL-1β　and　IL-18　were　detected　using　ELISA.　The　pyroptosis　of　THP-1　cells　was　detected　using　Annexin　V/PI　double-positive　staining.　Expression　of　proteins　associated　with　the　nucleotide-binding　oligomerization　domain,　leucine　rich　repeat　and　pyrin　domain-containing　protein　3　inflammasome　（NLRP3）,　including　NLRP3,　apoptosis　associated　speck-like　protein　（ASC）,　stimulated　the　cleavage　of　caspase-1　and　the　pyroptosis　executive　protein　Gasdermin　D　（GSDMD）,　were　measured　by　western　blotting.　PM2.5　significantly　inhibited　cell　viability,　induced　cell　swelling　and　cell　membrane　rupture,　and　increased　LDH　activity　in　THP-1　cells.　In　addition,　PM2.5　markedly　promoted　the　production　of　IL-1β　and　IL-18　by　THP-1　cells.　Treatment　with　PM2.5　significantly　increased　the　protein　of　NLRP3、ASC、pro-caspase-1,　Caspase-1,　GSDMD,　and　cleaved　gasdermin　D　（GSDMD-N）　in　THP-1　cells.　The　results　from　the　present　study　suggest　that　PM2.5　can　induce　the　pyroptosis　in　THP-1　cells.　©　2022　Science　Press.　All　rights　reserved.