Canine CXCL7 and its functional expression in dendritic cells undergoing maturation.
Many cells, including leucocytes and stromal cells, express CXCL7, a member of the CXC chemokine family, also known as platelet basic protein. CXCL7 is a potent chemoattractant and activator of neutrophil function. Dendritic cells (DCs) play a pivotal role in antigen processing and presentation. Very little information is available on the ability of DCs to recruit neutrophils by producing chemokines. In this work, we have cloned canine CXCL7. Based on the predicted gene sequence and using the 3'RACE technique, the full-length gene was amplified from LPS-treated canine peripheral blood mononuclear cells. The cloned cDNA sequence consisted of 357 nucleotides and encoded a 118 amino acid protein, including a 38 amino acid signal peptide. The use of CXCL7-containing supernatants from CXCL7-transfected BALB/3T3 in the neutrophil migration assay confirmed that canine CXCL7 had chemoattractive activity for neutrophils. We then used canine monocyte-derived DCs to generate CXCL7 for the rest of the experiment. Expression of CXCL7 by DCs treated with LPS, IL-1beta, IL-6, TGF-beta, TNF-alpha, or IFN-gamma was compared using real-time RT-PCR and Western blotting. When treated with IL-1beta, IL-6, TNF-alpha, or TGF-beta, canine DCs expressed significantly higher levels of CXCL7 mRNA and protein than when treated with IFN-gamma or LPS. It is concluded that dog DCs express high levels of the neutrophil chemotactic factor CXCL7 when stimulated by proinflammatory cytokines, including IL-1beta, IL-6, TNF-alpha, or TGF-beta, and may play an important role in modulating inflammatory responses.
Wang
Yu-Shan
YS
Animal Cancer Center, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC; Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan, ROC.
Liao
Kuang-Wen
KW
Department of Biological Sciences and Technology, College of Life Sciences, Hsin-Chu, Taiwan, ROC.
Chen
Mo-Fen
MF
Animal Cancer Center, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC.
Huang
Yi-Chun
YC
Animal Cancer Center, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC.
Chu
Rea-Min
RM
Animal Cancer Center, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC. Electronic address: redman@ntu.edu.tw.
Chi
Kwan-Hwa
KH
Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan, ROC. Electronic address: M006565@ms.skh.org.tw.
D000818:Animals; D041702:BALB 3T3 Cells; D015153:Blotting, Western / Q000662:veterinary; D019743:Chemokines, CXC / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D002634:Chemotaxis, Leukocyte / Q000276:immunology; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D003713:Dendritic Cells / Q000737:chemistry / Q000276:immunology* / Q000502:physiology; D004285:Dogs / Q000276:immunology; D005260:Female; D015870:Gene Expression / Q000235:genetics / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008297:Male; D051379:Mice; D009504:Neutrophils / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D016415:Sequence Alignment; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000662:veterinary
D019743:Chemokines, CXC; D018076:DNA, Complementary