title: Use of complement regulators, CD35, CD46, CD55, and CD59, on leukocytes as markers for diagnosis of viral and bacterial infections.
abstract: Several complement regulatory proteins exist on self-cells to prevent damage by the serum complement system. In the present study, we aimed to perform quantitative analysis of membrane-bound complement regulators, CR1 (CD35), MCP (CD46), DAF (CD55), and MIRL (CD59), on peripheral blood neutrophils, monocytes, and lymphocytes from healthy controls (n=36) and febrile patients diagnosed with either bacterial (n=21) or viral (n=26) infections. Our results show that: (a) increased CD35 and CD55 levels on neutrophils and monocytes present potent markers of bacterial infection, (b) increased expression of CD46 on monocytes is an indicator of viral infection, and (c) increased CD59 expression on neutrophils and monocytes is a general infection marker. Additionally, CD19-positive B-lymphocytes represent practically the only lymphocyte population capable of expressing CD35. We further developed two novel clinical flow cytometric markers (indices), specifically, clinical mononucleosis (CM)-INDEX (incorporating CD35, CD55, and CD59 expression on lymphocytes) and clinical bacterial infection (CBI)-INDEX (incorporating CD35 and CD55 expression on neutrophils and lymphocytes), for the effective detection of viral mononucleosis and bacterial infection, respectively. In summary, bacterial and viral infections induce different expression patterns of membrane-bound complement regulators in human leukocytes, which may be effectively exploited in clinical differential diagnosis.
authors: Department of Biochemistry, University of Turku, Turku, Finland. jarnuu@utu.fi
authors: Jari
authors: J
authors: Nuutila
authors: Päivi
authors: P
authors: Jalava-Karvinen
authors: Ulla
authors: U
authors: Hohenthal
authors: Pirkko
authors: P
authors: Kotilainen
authors: Tarja-Terttu
authors: TT
authors: Pelliniemi
authors: Jukka
authors: J
authors: Nikoskelainen
authors: Esa-Matti
authors: EM
authors: Lilius
mesh_terms: D000328:Adult; D000368:Aged; D001424:Bacterial Infections / Q000097:blood / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D018958:CD55 Antigens / Q000097:blood*; D018957:CD59 Antigens / Q000097:blood*; D003169:Complement Inactivator Proteins / Q000032:analysis; D003937:Diagnosis, Differential; D005434:Flow Cytometry; D006801:Humans; D007244:Infectious Mononucleosis / Q000097:blood / Q000175:diagnosis*; D007962:Leukocytes / Q000378:metabolism*; D008214:Lymphocytes / Q000378:metabolism; D051916:Membrane Cofactor Protein / Q000097:blood*; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism; D017463:Receptors, Complement 3b / Q000097:blood*; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D015415:Biomarkers; D018958:CD55 Antigens; D018957:CD59 Antigens; D003169:Complement Inactivator Proteins; D051916:Membrane Cofactor Protein; D017463:Receptors, Complement 3b