title: Quantification of complement system activation by measuring C5b-9 cell surface deposition using a cell-ELISA technique.
abstract: The complement system is an important aspect of immune defense against microbial invasion. Eukaryotic cells express various complement regulatory proteins to protect them from uncontrolled complement activation. However, some eukaryotic cells possess constitutive complement system activation that does not require specific triggering factors, which is known to have unexpected effects on cell proliferation and survival. This area of research is still preliminary and a standard method to measure complement system activation in eukaryotic cells has yet to be identified. Here, we present a quantitative in vitro method to measure complement system activation in eukaryotic cells by detecting C5b-9, the membrane attack complex, on cell surfaces. The results obtained using this assay correlated with C3b deposition measured using flow cytometry and C5b-9 deposition detected using an immunofluorescence assay. Furthermore, we showed that various cancer cell lines displayed different levels of complement system activation by using this assay.
authors.affiliation: Department of Microbiology and Immunology, Eulji University School of Medicine, Daejeon, South Korea.
authors.forename: Hyungtaek
authors.initials: H
authors.lastname: Jeon
authors.affiliation: Department of Microbiology and Immunology, Eulji University School of Medicine, Daejeon, South Korea.
authors.forename: Ji-Su
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Microbiology and Immunology, Eulji University School of Medicine, Daejeon, South Korea.
authors.forename: Seungmin
authors.initials: S
authors.lastname: Yoo
authors.affiliation: Department of Microbiology and Immunology, Eulji University School of Medicine, Daejeon, South Korea. Electronic address: mslee@eulji.ac.kr.
authors.forename: Myung-Shin
authors.initials: MS
authors.lastname: Lee
mesh_terms: D000906:Antibodies / Q000494:pharmacology; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology; D015816:Cell Adhesion Molecules, Neuronal / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000737:chemistry* / Q000276:immunology; D003167:Complement Activation; D003179:Complement C3b / Q000494:pharmacology; D015938:Complement Membrane Attack Complex / Q000032:analysis*; D000071063:Endoglin; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005326:Fetal Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology; D005434:Flow Cytometry; D015870:Gene Expression; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D009928:Organ Specificity; D011956:Receptors, Cell Surface / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology; D020410:Activated-Leukocyte Cell Adhesion Molecule
chemical_list: D000906:Antibodies; D015703:Antigens, CD; D015816:Cell Adhesion Molecules, Neuronal; D003179:Complement C3b; D015938:Complement Membrane Attack Complex; D000071063:Endoglin; D005326:Fetal Proteins; D011956:Receptors, Cell Surface; C105613:ALCAM protein, human; D020410:Activated-Leukocyte Cell Adhesion Molecule; C064206:ENG protein, human; C047610:SC5b-9 protein complex
keywords: Complement system; ELISA; Membrane attack complex