Alternative Polyadenylation Events Contribute to the Induction of NF-ATc in Effector T Cells

Abstract The transcription factor NF-ATc is synthesized in three prominent isoforms. These differ in the length of their C terminal peptides and mode of synthesis. Due to a switch from the use of a 3′ polyA site to a more proximal polyA site, NF-ATc expression switches from the synthesis of the two longer isoforms in naive T cells to that of short isoform A in T effector cells. The relative low binding affinity of cleavage stimulation factor CstF-64 to the proximal polyA site seems to contribute to its neglect in naive T cells. These alternative polyadenylation events ensure the rapid accumulation of high concentrations of NF-ATc necessary to exceed critical threshold levels of NF-ATc for g…

Kappa free light chains in cerebrospinal fluid as markers of intrathecal immunoglobulin synthesis.

Abstract Background: Intrathecal immunoglobulin synthesis is observed in several inflammatory disorders of the central nervous system, but its detection by current laboratory tests is either tedious or relatively insensitive. We assessed the diagnostic accuracy of an assay for κ free light chains (κFLC) in cerebrospinal fluid (CSF) and serum, and compared it with traditional tests for intrathecal immunoglobulin synthesis. Methods: κFLCs were measured by nephelometry in CSF/serum pairs from 112 patients. Samples were excluded if blood contamination of CSF as a result of traumatic lumbar puncture (n = 12) or monoclonal bands in both CSF and serum (n = 5) were present. The remaining sample pai…

Identification of a peptide mimicking the binding pattern of an antiphospholipid antibody

Our objective was to characterize monoclonal antiphospholipid antibodies (APL) and identify disease-associated antigens in patients with the antiphospholipid syndrome (APS). We used the monoclonal antibody HL-5B, derived from a patient with APS suffering from multiple ischemic events, to screen a 12-mer peptide phage display library (New England Biolabs, London, England). The identified phage clones were sequenced and the derived consensus peptide was synthesized. The peptide was used to perform competitive inhibition experiments for their ability to inhibit the binding of the monoclonal antibody and of serum antibodies to cardiolipin and phosphatidylserine. Additionally patients and contro…

Generation and characterization of three monoclonal IgM antiphospholipid antibodies recognizing different phospholipid antigens.

Antiphospholipid antibodies (APLs) might be involved in the pathogenesis of the antiphospholipid syndrome (APS). This study analyzes the structural characteristics of monoclonal APLs derived from patients with this disease. Patient-derived B cells were immortalized using Epstein-Barr virus transformation and subsequent fusion to the myeloma cell line CB-F7. APL-producing hybridomas were cloned to obtain cell lines producing monoclonal APL. DNA encoding the variable region of heavy and light chains of the antibodies was sequenced and analyzed regarding their usage within the V-gene family and the existence of somatic hypermutation. Binding patterns of APL to various phospholipids and beta-2-…

NF-ATp plays a prominent role in the transcriptional induction of Th2-type lymphokines