{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T16:36:37Z","timestamp":1769013397574,"version":"3.49.0"},"reference-count":33,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2020,3,15]],"date-time":"2020-03-15T00:00:00Z","timestamp":1584230400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31272542"],"award-info":[{"award-number":["31272542"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["IJMS"],"abstract":"<jats:p>The polymorphic membrane protein D (PmpD) is a highly conserved outer membrane protein which plays an important role in pathogenesis during Chlamydia psittaci infection. In this study, we evaluated the ability of the N-terminus of PmpD (PmpD-N) to modulate the functions of chicken macrophages and the signaling pathway(s) involved in PmpD-N-induced Toll-like receptors (TLRs), as well as interleukin (IL)-6 and IL-10 cytokine secretions. Thus, HD11 macrophages were treated with exogenous and intracellular PmpD-N of C. psittaci. The chlamydial growth was evaluated by enumeration of chlamydial loads in the infected macrophages. The phagocytic function of macrophages following PmpD-N treatment was detected by fluorescein-labeled Escherichia coli (E. coli). The concentration of nitric oxide (NO) secreted by HD11 macrophages was measured by the amount of NO2- in the culture supernatant using the Griess method. The cytokine secretions were assessed using multiplex cytokine ELISA kits. Expression levels of TLRs, myeloid differentiation factor 88 (MyD88), and nuclear factor kappa B (NF-\u03baB) were analyzed by a Western blotting assay, as well as a luciferase assay, while NF-\u03baB p65 nuclear translocation was assessed by confocal microscopy. The nuclear translocation of the transcription factor NF-\u03baB was confirmed by evaluating its ability to combine with the corresponding promoter using the electrophoretic mobility shift assay (EMSA). After treatment with exogenous or endogenous PmpD-N, chlamydial loads and phagocytic functions were reduced significantly compared with those of the plasmid vector group, while NO secretions were reduced significantly compared with those of the lipopolysaccharide (LPS) treatment. Stimulation of HD11 cells with PmpD-N provoked the secretion of the Th2 cytokines, IL-6, and IL-10 and upregulated the expression of TLR2, TLR4, MyD88, and NF-\u03baB. Furthermore, inhibition of TLR2, MyD88, and NF-\u03baB in HD11 cells significantly decreased IL-6 and IL-10 cytokine levels, while NO production and phagocytosis increased significantly, strongly suggesting their involvement in PmpD-N-induced Th2 cytokine secretion and macrophage dysfunction. Our data indicate that C. psittaci PmpD-N inhibited macrophage functions by activating the Th2 immune response and the TLR2\/MyD88\/NF-\u03baB signaling pathway.<\/jats:p>","DOI":"10.3390\/ijms21062003","type":"journal-article","created":{"date-parts":[[2020,3,18]],"date-time":"2020-03-18T08:13:27Z","timestamp":1584519207000},"page":"2003","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["Chlamydia psittaci PmpD-N Modulated Chicken Macrophage Function by Triggering Th2 Polarization and the TLR2\/MyD88\/NF-\u03baB Signaling Pathway"],"prefix":"10.3390","volume":"21","author":[{"given":"Jun","family":"Chu","sequence":"first","affiliation":[{"name":"Key Lab of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China"},{"name":"Beijing Key Laboratory for Prevention and Control of Infectious Diseases in Livestock and Poultry, Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaohui","family":"Li","sequence":"additional","affiliation":[{"name":"Key Lab of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guanggang","family":"Qu","sequence":"additional","affiliation":[{"name":"Shandong Binzhou Animal Science and Veterinary Medicine Academy, Binzhou 256600, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yihui","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Lab of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiang","family":"Li","sequence":"additional","affiliation":[{"name":"Key Lab of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongxia","family":"Guo","sequence":"additional","affiliation":[{"name":"Key Lab of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lei","family":"Hou","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory for Prevention and Control of Infectious Diseases in Livestock and Poultry, Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jue","family":"Liu","sequence":"additional","affiliation":[{"name":"Beijing Key Laboratory for Prevention and Control of Infectious Diseases in Livestock and Poultry, Institute of Animal Husbandry and Veterinary Medicine, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francis","family":"Eko","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1223-9639","authenticated-orcid":false,"given":"Cheng","family":"He","sequence":"additional","affiliation":[{"name":"Key Lab of Animal Epidemiology and Zoonosis of the Ministry of Agriculture, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"382","DOI":"10.1016\/j.vetmic.2009.03.014","article-title":"Zoonotic potential of Chlamydophila","volume":"140","author":"Rodolakis","year":"2010","journal-title":"Vet. Microbiol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1093\/infdis\/163.2.233","article-title":"Cofactors in male-female sexual transmission of human immunodeficiency virus type 1","volume":"163","author":"Plummer","year":"1991","journal-title":"J. Infect. Dis."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3244","DOI":"10.1128\/JCM.00698-10","article-title":"Chlamydophila psittaci zoonotic risk assessment in a chicken and turkey slaughterhouse","volume":"48","author":"Dickx","year":"2010","journal-title":"J. Clin. Microbiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"399","DOI":"10.1099\/jmm.0.064675-0","article-title":"Emerging Chlamydia psittaci infections in chickens and examination of transmission to humans","volume":"63","author":"Lagae","year":"2014","journal-title":"J. Med. Microbiol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"728","DOI":"10.1126\/science.1096330","article-title":"Illuminating the evolutionary history of chlamydiae","volume":"304","author":"Horn","year":"2004","journal-title":"Science"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2831","DOI":"10.1002\/pmic.200400940","article-title":"Genome and proteome analysis of Chlamydia","volume":"4","author":"Vandahl","year":"2004","journal-title":"Proteomics"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Voigt, A., Schofl, G., and Saluz, H.P. (2012). The Chlamydia psittaci genome: A comparative analysis of intracellular pathogens. PLoS ONE, 7.","DOI":"10.1371\/journal.pone.0035097"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1089\/omi.1.1999.4.187","article-title":"Computational analysis of the polymorphic membrane protein superfamily of Chlamydia trachomatis and Chlamydia pneumoniae","volume":"4","author":"Grimwood","year":"1999","journal-title":"Microb. Comp. Genom."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Van Lent, S., De Vos, W.H., Huot Creasy, H., Marques, P.X., Ravel, J., Vanrompay, D., Bavoil, P., and Hsia, R.C. (2016). Analysis of polymorphic membrane protein expression in cultured cells identifies PmpA and PmpH of Chlamydia psittaci as candidate factors in pathogenesis and immunity to infection. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0162392"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1128\/iai.14.1.277-289.1976","article-title":"Immediate toxicity of high multiplicities of Chlamydia psittaci for mouse fibroblasts (L cells)","volume":"14","author":"Moulder","year":"1976","journal-title":"Infect. Immun."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"638","DOI":"10.1128\/iai.12.3.638-646.1975","article-title":"Ultrastructural cytochemical evidence for the activation of lysosomes in the cytocidal effect of Chlamydia psittaci","volume":"12","author":"Todd","year":"1975","journal-title":"Infect. Immun."},{"key":"ref_12","unstructured":"L\u00e9pinay, A., Orfila, J., Anteunis, A., Boutry, J., Orme-Roselli, L., and Robineaux, R. (1970). Study with electron microscopy of the development and morphology of Chlamydia psittaci in mouse macrophages. Annales de l\u2019Institut Pasteur."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Kiselev, A.O., Stamm, W.E., Yates, J.R., and Lampe, M.F. (2007). Expression, processing, and localization of PmpD of Chlamydia trachomatis serovar L2 during the chlamydial developmental cycle. PLoS ONE, 2.","DOI":"10.1371\/journal.pone.0000568"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1046\/j.1365-2958.2003.03838.x","article-title":"From the inside out\u2014Processing of the chlamydial autotransporter PmpD and its role in bacterial adhesion and activation of human host cells","volume":"51","author":"Wehrl","year":"2004","journal-title":"Mol. Microbiol."},{"key":"ref_15","first-page":"315","article-title":"Development of a novel PmpD-N ELISA for Chlamydia psittaci infection","volume":"29","author":"Liu","year":"2016","journal-title":"Biomed. Environ. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"221","DOI":"10.3389\/fvets.2017.00221","article-title":"A promising recombinant herpesvirus of turkeys vaccine expressing PmpD-N of Chlamydia psittaci based on elongation factor-1 alpha promoter","volume":"4","author":"Liu","year":"2017","journal-title":"Front. Vet. Sci."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1086\/375827","article-title":"Polymorphic membrane protein (PMP) 20 and PMP 21 of Chlamydia pneumoniae induce proinflammatory mediators in human endothelial cells In Vitro by activation of the nuclear factor-kappaB pathway","volume":"188","author":"Niessner","year":"2003","journal-title":"J. Infect. Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2756","DOI":"10.1128\/IAI.01686-14","article-title":"Chlamydia trachomatis polymorphic membrane protein D is a virulence factor involved in early host-cell interactions","volume":"82","author":"Kari","year":"2014","journal-title":"Infect. Immun."},{"key":"ref_19","first-page":"439","article-title":"Proliferation of macrophages due to the inhibition of inducible nitric oxide synthesis by oxidized low-density lipoproteins","volume":"14","author":"Brunner","year":"2015","journal-title":"EXCLI J."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1016\/j.jchromb.2018.05.029","article-title":"Broad application and optimization of a single wash-step for integrated endotoxin depletion during protein purification","volume":"1091","author":"Koziel","year":"2018","journal-title":"J. Chromatogr. B Anal. Technol. Biomed. Life Sci."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1016\/0092-8674(79)90057-6","article-title":"Chicken hematopoietic cells transformed by seven strains of defective avian leukemia viruses display three distinct phenotypes of differentiation","volume":"18","author":"Beug","year":"1979","journal-title":"Cell"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1265","DOI":"10.1128\/iai.64.4.1265-1271.1996","article-title":"Ultrastructural changes in avian Chlamydia psittaci serovar A-, B-, and D-infected buffalo green monkey cells","volume":"64","author":"Vanrompay","year":"1996","journal-title":"Infect. Immun."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"29421","DOI":"10.1038\/srep29421","article-title":"Chlamydia psittaci infection increases mortality of avian influenza virus H9N2 by suppressing host immune response","volume":"6","author":"Chu","year":"2016","journal-title":"Sci. Rep."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1146\/annurev.immunol.15.1.323","article-title":"Nitric oxide and macrophage function","volume":"15","author":"MacMicking","year":"1997","journal-title":"Annu. Rev. Immunol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"812","DOI":"10.1016\/j.dci.2010.03.001","article-title":"Differential cytokine expression in Chlamydophila psittaci genotype A-, B- or D-infected chicken macrophages after exposure to Escherichia coli O2:K1 LPS","volume":"34","author":"Beeckman","year":"2010","journal-title":"Dev. Comp. Immunol."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Zhang, Y., Wang, H., Ren, J., Tang, X., Jing, Y., Xing, D., Zhao, G., Yao, Z., Yang, X., and Bai, H. (2012). IL-17A synergizes with IFN-gamma to upregulate iNOS and No production and inhibit chlamydial growth. PLoS ONE, 7.","DOI":"10.1371\/journal.pone.0039214"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3164","DOI":"10.1128\/IAI.00382-15","article-title":"Chlamydia muridarum infection of macrophages elicits bactericidal nitric oxide production via reactive oxygen species and cathepsin B","volume":"83","author":"Rajaram","year":"2015","journal-title":"Infect. Immun."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"593","DOI":"10.2174\/138161208783885344","article-title":"Role of toll-like receptors in immune responses to chlamydial infections","volume":"14","author":"Joyee","year":"2008","journal-title":"Curr. Pharm. Des."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"439","DOI":"10.1111\/mmi.13245","article-title":"Interference with nuclear factor kappaB signaling pathway by pathogen-encoded proteases: Global and selective inhibition","volume":"99","author":"Hodgson","year":"2016","journal-title":"Mol. Microbiol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"514","DOI":"10.3389\/fcimb.2017.00514","article-title":"Chlamydia abortus Pmp18.1 induces IL-1beta secretion by TLR4 activation through the MyD88, NF-kappaB, and caspase-1 signaling pathways","volume":"7","author":"Pan","year":"2017","journal-title":"Front. Cell. Infect. Microbiol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1158","DOI":"10.4049\/jimmunol.180.2.1158","article-title":"The proinflammatory cytokine response to Chlamydia trachomatis elementary bodies in human macrophages is partly mediated by a lipoprotein, the macrophage infectivity potentiator, through TLR2\/TLR1\/TLR6 and CD14","volume":"180","author":"Bas","year":"2008","journal-title":"J. Immunol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"4662","DOI":"10.1128\/IAI.00993-15","article-title":"Interleukin-10 modulates antigen presentation by dendritic cells through regulation of NLRP3 inflammasome assembly during Chlamydia infection","volume":"83","author":"Omosun","year":"2015","journal-title":"Infect. Immun."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1503","DOI":"10.1073\/pnas.022649799","article-title":"Human macrophage activation programs induced by bacterial pathogens","volume":"99","author":"Nau","year":"2002","journal-title":"Proc. Natl. Acad. Sci. USA"}],"updated-by":[{"DOI":"10.3390\/ijms21072639","type":"correction","label":"Correction","source":"publisher","updated":{"date-parts":[[2020,3,15]],"date-time":"2020-03-15T00:00:00Z","timestamp":1584230400000}}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/21\/6\/2003\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,3]],"date-time":"2025-08-03T22:20:33Z","timestamp":1754259633000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/21\/6\/2003"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,3,15]]},"references-count":33,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2020,3]]}},"alternative-id":["ijms21062003"],"URL":"https:\/\/doi.org\/10.3390\/ijms21062003","relation":{"correction":[{"id-type":"doi","id":"10.3390\/ijms21072639","asserted-by":"object"}]},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,3,15]]}}}