caa a22 4500 475748581 CHVBK 20180406123520.0 cr unu---uuuuu 170329e20000301xx s 000 0 eng 10.1023/A:1006686514743 doi (NATIONALLICENCE)springer-10.1023/A:1006686514743 Urine Free Light Chains in SLE: Clonal Markers of B-Cell Activity and Potential Link to In Vivo Secreted IG [Elektronische Daten] [John Hopper, Joseph Golbus, Catherine Meyer, Gerrard Ferrer] As a marker of in vivo B-cell activity, urine levels of free light chain (FLC) were measured twice weekly by radioimmunassay (RIA) and correlated with disease activity over periods of 5-10 months in seven patients with systemic lupus erythematousus (SLE). In addition, RIA-measured urine albumin was used to track glomerular injury, and α1-microglobulin (α1-M) levels, 28- to 32-kDa protein, provided control measurements on excretion of low-molecular-weight proteins. As controls, urine FLC levels were obtained from healthy normals and in subjects with acute pharyngitis, sickle-cell anemia, and acute sepsis or pneumonia. The control results showed that with acute sepsis/pneumonia had marked increases in urine FLC, while pharyngitis and sickle-cell controls had normal FLC levels. In SLE, active patients receiving intravenous cyclophsophamide and high-dose steroids exhibited highly increased urine FLC that fluctuated widely during therapy and fell to normal range levels with disease remission. During active SLE, urine albumin often was increased, while α1-M levels remained in normal range. In contrast to the increased FLC of active disease, inactive patients on low-dose maintenance therapy had predominantly normal FLC levels throughout the collection period. These results support our hypothesis that longitudinal levels of urine FLC can be used to track disease-related B-cell activity in SLE. Furthermore, we suggest that the urine FLC of active SLE would share LC idiotype with the clonal associated in vivo secreted Ig, and thus permit the identification of these antibodies that are targeted to the culprit immunogen(s) responsible for the pathogenesis of SLE. Plenum Publishing Corporation, 2000 Systemic lupus erythematosus nationallicence urine free light chain nationallicence disease activity nationallicence B-cell activity nationallicence Hopper John Department of Medicine, University of Illinois, 60612, Chicago, Illinois, USA aut Golbus Joseph Division of Rheumatology, Evanston Hospital, 60201., Evanston, Illinois, USA aut Meyer Catherine Section of Rheumatology, Mercy Hospital, 60616, Chicago, Illinois, USA aut Ferrer Gerrard Department of Medicine, University of Illinois, 60612, Chicago, Illinois, USA aut Journal of Clinical Immunology Kluwer Academic Publishers-Plenum Publishers 20/2(2000-03-01), 123-137 0271-9142 20:2<123 2000 20 10875 https://doi.org/10.1023/A:1006686514743 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1006686514743 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hopper John Department of Medicine, University of Illinois, 60612, Chicago, Illinois, USA aut NATIONALLICENCE 700 1- Golbus Joseph Division of Rheumatology, Evanston Hospital, 60201., Evanston, Illinois, USA aut NATIONALLICENCE 700 1- Meyer Catherine Section of Rheumatology, Mercy Hospital, 60616, Chicago, Illinois, USA aut NATIONALLICENCE 700 1- Ferrer Gerrard Department of Medicine, University of Illinois, 60612, Chicago, Illinois, USA aut NATIONALLICENCE 773 0- Journal of Clinical Immunology Kluwer Academic Publishers-Plenum Publishers 20/2(2000-03-01), 123-137 0271-9142 20:2<123 2000 20 10875 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer