{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T03:05:22Z","timestamp":1792033522372,"version":"4.4.0"},"reference-count":26,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,29]],"date-time":"2022-07-29T00:00:00Z","timestamp":1659052800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea (NRF)","award":["NRF-2018R1D1A1B07048097"],"award-info":[{"award-number":["NRF-2018R1D1A1B07048097"]}]},{"name":"National Research Foundation of Korea (NRF)","award":["NRF-2021R1A2C1091855"],"award-info":[{"award-number":["NRF-2021R1A2C1091855"]}]},{"name":"Korean government","award":["NRF-2018R1D1A1B07048097"],"award-info":[{"award-number":["NRF-2018R1D1A1B07048097"]}]},{"name":"Korean government","award":["NRF-2021R1A2C1091855"],"award-info":[{"award-number":["NRF-2021R1A2C1091855"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Naegleria fowleri is a ubiquitous protozoa parasite that can cause primary amoebic meningoencephalitis (PAM), a fatal brain infection in humans. Cathepsin Bs of N. fowleri (NfCBs) are multifamily enzymes. Although their pathogenic mechanism in PAM is not clearly understood yet, NfCBs have been proposed as pathogenic factors involved in the pathogenicity of amoeba. In this study, the immune response of BV-2 microglial cells induced by NfCB was analyzed. Recombinant NfCB (rNfCB) evoked enhanced expressions of TLR-2, TLR-4, and MyD88 in BV-2 microglial cells. This enzyme also induced an elevated production of several pro-inflammatory cytokines such as TNF-\u03b1, IL-1\u03b1, IL-1\u03b2, and IL-6 and iNOS in cells. The inhibition of mitogen-activated protein kinases (MAPKs), including JNK, p38, and ERK, effectively reduced the production of these pro-inflammatory cytokines. The rNfCB-induced production of pro-inflammatory cytokines in BV-2 microglial cells was suppressed by inhibiting NF-kB and AP-1. Phosphorylation and nuclear translocation of p65 in cells were also enhanced by rNfCB. These results suggest that NfCB can induce a pro-inflammatory immune response in BV-2 microglial cells via the NF-\u03baB- and AP-1-dependent MAPK signaling pathways. Such a NfCB-induced pro-inflammatory immune response in BV-2 microglial cells might contribute to the pathogenesis of PAM caused by amoeba, by exacerbating deleterious immune responses and tissue damages in N. fowleri-infected foci of the brain.<\/jats:p>","DOI":"10.3390\/ijms23158388","type":"journal-article","created":{"date-parts":[[2022,7,31]],"date-time":"2022-07-31T23:37:29Z","timestamp":1659310649000},"page":"8388","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Naegleria fowleri Cathepsin B Induces a Pro-Inflammatory Immune Response in BV-2 Microglial Cells via NF-\u03baB and AP-1 Dependent-MAPK Signaling Pathway"],"prefix":"10.3390","volume":"23","author":[{"given":"H\u01b0\u01a1ng Giang","family":"L\u00ea","sequence":"first","affiliation":[{"name":"Department of Parasitology and Tropical Medicine, and Institute of Health Sciences, Gyeongsang National University College of Medicine, Jinju 52727, Korea"},{"name":"Department of Convergence Medical Science, Gyeongsang National University, Jinju 52727, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jung-Mi","family":"Kang","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Tropical Medicine, and Institute of Health Sciences, Gyeongsang National University College of Medicine, Jinju 52727, Korea"},{"name":"Department of Convergence Medical Science, Gyeongsang National University, Jinju 52727, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tu\u1ea5n C\u01b0\u1eddng","family":"V\u00f5","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Tropical Medicine, and Institute of Health Sciences, Gyeongsang National University College of Medicine, Jinju 52727, Korea"},{"name":"Department of Convergence Medical Science, Gyeongsang National University, Jinju 52727, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6734-1673","authenticated-orcid":false,"given":"Byoung-Kuk","family":"Na","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Tropical Medicine, and Institute of Health Sciences, Gyeongsang National University College of Medicine, Jinju 52727, Korea"},{"name":"Department of Convergence Medical Science, Gyeongsang National University, Jinju 52727, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6677","DOI":"10.1128\/AAC.01293-15","article-title":"Naegleria fowleri: Pathogenesis, diagnosis, and treatment options","volume":"59","author":"Grace","year":"2015","journal-title":"Antimicrob. 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