[C-reactive protein and lactate dehydrogenase as single prognostic factors of severity in acute pancreatitis].

Ranson and Glasgow scores are routinely used for prediction of severity in acute pancreatitis. We undertook a prospective study to investigate the role of lactate dehydrogenase (LDH) and C-reactive protein (CRP) as potential single predictors of severity in acute pancreatitis. In our study we included 100 patients with diagnosis of acute pancreatitis admitted to our hospital during last two years.

The role of nonenhanced magnetic resonance imaging in the early assessment of acute pancreatitis.

Background And Aims: Computed tomography (CT), especially contrast-enhanced CT (CECT), provides important information on the severity and prognosis of acute pancreatitis (AP). Magnetic resonance imaging (MRI) has become a useful tool as an alternative to CT in the assessment of AP. The primary aim of our study was to determine the diagnostic value of nonenhanced MRI (NEMRI) to assess severity and predict outcome in patients with AP from the third to fifth day after admission.

Pulmonary embolism due to the right atrial myxoma.

A 47-year-old man was admitted to the hospital with a pleuritic pain, dyspnea, nonproductive cough and low-grade fever. An ECG documented a sinus tachycardia with S1Q3T3 pattern and incomplete right bundle branch block, and lung scintigraphy showed multiple perfusion defects. The initial diagnosis was pulmonary embolism.

Gender differences in in-hospital mortality and mechanisms of death after the first acute myocardial infarction.

Background: There are conflicting data about gender differences in short-term mortality after acute myocardial infarction (AMI) after adjusting for age and other prognostic factors. Therefore, we investigated the risk profile, clinical presentation, in-hospital mortality and mechanisms of death in women and men after the first AMI.

Methods: The data were obtained from a chart review of 3382 consecutive patients, 1184 (35%) women (69.

Divergent members of a single autoreactive B cell clone retain specificity for apoptotic blebs.

Specificity for double-stranded DNA can arise due to somatic mutations within one of the branches of an autoreactive B cell clone. However, it is not known whether a different autospecificity predates anti-dsDNA and whether separate offshoots of an expanding B cell clone retain or evolve alternative specificities. We compared 3H9, an anti-dsDNA IgG, to 4H8 and 1A11, antibodies produced by hybridomas representing an alternative branch of the 3H9 B cell clone.

The level of anti-topoisomerase I antibodies highly correlates with metacarpophalangeal and proximal interphalangeal joints flexion contractures in patients with systemic sclerosis.

Background: It is found that an antibody directed against DNA topoisomerase I (anti-topo I abs) is detected almost exclusively in systemic sclerosis (SSc). These antibodies are predictors of pulmonary fibrosis and peripheral vascular disease.

Objective: Metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints flexion contractures are assessed as markers of active SSc.

Development of functional B cells in a line of SCID mice with transgenes coding for anti-double-stranded DNA antibody.

Deletion or inactivation of anti-self (DNA) B cells has been reported in non-autoimmune mice bearing Ig transgenes that code for Abs with specificity for dsDNA or ssDNA. However, we report a case in which anti-dsDNA B cells appear to escape both deletion and inactivation. We show that B cells (B220+IgM+) can develop in non-autoimmune SCID mice bearing two site-directed transgenes, 3H9(56R) and Vkappa8, that together code for an anti-dsDNA Ab.

Heterogeneous nuclear ribonucleoprotein P2 is an autoantibody target in mice deficient for Mer, Axl, and Tyro3 receptor tyrosine kinases.

Deficiencies in clearance of apoptotic cells predispose to the development of autoimmune disease. This is evident in mice lacking the receptor tyrosine kinases Tyro3, Axl, and Mer. Deficient mice exhibit an increased abundance of apoptotic cells in tissues and manifest diverse autoimmune conditions.

Murine lupus autoantibodies identify distinct subsets of apoptotic bodies.

The specific modification of autoantigens and their redistribution into blebs at the surface of apoptotic cells contribute to the induction of autoimmune responses. Blebs containing fragments of the apoptotic nucleus separate from the remainder of the cell to form membrane-bound sub-cellular particles (SCPs), otherwise known as apoptotic bodies. To determine whether apoptotic bodies containing nuclear antigens represent a defined subset of SCPs, we examined the heterogeneity of particles generated by Jurkat cells following synchronization of the cell cycle by serum withdrawal and inhibition of topoisomerase I by camptothecin.

Apoptosis, subcellular particles, and autoimmunity.

Firm evidence links the process of apoptosis to the induction of autoimmune disease. However, questions remain regarding the precise interactions of dying cells with the immune system. Genetic analyses indicate that deficiencies in serum proteins or receptors that mediate clearance of apoptotic cells increase the risk of autoimmunity.

Nucleosomes are exposed at the cell surface in apoptosis.

Apoptotic cells are considered the source of DNA, histones, and nucleoprotein complexes that drive the production of autoantibodies in systemic lupus erythematosus. However, the role of apoptotic cells in the activation of the immune system is not clear. To explore interactions that may initiate or sustain the production of anti-nuclear autoantibodies, we characterized the binding of a large panel of monoclonal autoantibodies to apoptotic cells.

Kappa editing rescues autoreactive B cells destined for deletion in mice transgenic for a dual specific anti-laminin Ig.

We explored mechanisms involved in B cell self-tolerance in a double- and triple-transgenic mouse model bearing the LamH-C mu Ig H chain conventional transgene and a gene-targeted replacement for a functional V kappa 8J kappa 5 L chain gene. Whereas the H chain is known to generate anti-laminin Ig in combination with multiple L chains, the H + L Ig binds ssDNA in addition to laminin. Immune phenotyping indicates that H + L transgenic B cells are regulated by clonal deletion, receptor editing via secondary rearrangements at the nontargeted kappa allele, and anergy.

Regulation of anti-phosphatidylserine antibodies.

The degree of heavy chain (H) editing, the types of Vkappa editors, and the pattern of Jkappa usage are correlated with a range of the affinity of anti-DNA. This range was determined by the number and location of arginine (R) residues in the VH. We, here, changed a key arginine residue in the VH of anti-DNA transgene to glycine, which sharply reduces the affinity for dsDNA.

DNA-dependent protein kinase activity is not required for immunoglobulin class switching.

Class switch recombination (CSR), similar to V(D)J recombination, is thought to involve DNA double strand breaks and repair by the nonhomologous end-joining pathway. A key component of this pathway is DNA-dependent protein kinase (DNA-PK), consisting of a catalytic subunit (DNA-PKcs) and a DNA-binding heterodimer (Ku70/80). To test whether DNA-PKcs activity is essential for CSR, we examined whether IgM(+) B cells from scid mice with site-directed H and L chain transgenes were able to undergo CSR.

Blebs and apoptotic bodies are B cell autoantigens.

Mounting evidence suggests that systemic lupus erythematosus autoantigens are derived from apoptotic cells. To characterize the potential interactions between apoptotic cells and B cells, the D56R/S76R variant of 3H9, a murine autoantibody that binds to DNA, chromatin, and anionic phospholipids, was compared with DNA4/1, a human anti-DNA autoantibody. Flow cytometry revealed that only D56R/S76R bound to Jurkat cells treated with either of three distinct proapoptotic stimuli, Ab binding was dependent on caspase activity, and immunoreactivity developed subsequent to annexin V binding.

Editors and editing of anti-DNA receptors.

Receptor editing is a means by which immature bone marrow B cells can become self-tolerant. Rearrangements of heavy (H) and/or light (L) chain genes are induced by encounter with autoantigens to change the specificity from self to nonself. We have developed site-directed transgenic mice (sd-tg) whose transgenes code for the H chain of antibodies that bind DNA.

Structural basis for autoantibody recognition of phosphatidylserine-beta 2 glycoprotein I and apoptotic cells.

Apoptotic cells contain nuclear autoantigens that may initiate a systemic autoimmune response. To explore the mechanism of antibody binding to apoptotic cells, 3H9, a murine autoantibody with dual specificity for phospholipids and DNA, was used. H chain mutants of 3H9 were constructed, expressed as single-chain Fv (scFv) in Escherichia coli, and assessed for binding to phosphatidylserine, an antigen expressed on apoptotic cells.

Diverse roles for the third complementarity determining region of the heavy chain (H3) in the binding of immunoglobulin Fv fragments to DNA, nucleosomes and cardiolipin.

Autoantibodies to DNA and chromatin employ junctional diversity and somatic mutations to generate or enhance antigen recognition. To define the role of diversity generating mechanisms in the etiology of autoantibodies to nuclear antigens, the heavy (H) chain of a murine autoantibody, 3H9, was used in its somatically mutated or germ-line form in conjunction with its own or with heterologous CDR3 (H3) domains. The resulting H chains were expressed together with the 3H9 light (L) chain as single-chain Fv (scFv) in Escherichia coli and assayed for binding to DNA, nucleosomes, or cardiolipin by enzyme-linked immunosorbent assay.

Genes coding evolutionary novel anti-carbohydrate antibodies: studies on anti-Gal production in alpha 1,3galactosyltransferase knock out mice.

This study analyzes the gene repertoire coding for antibodies to an evolutionary novel immunogenic carbohydrate antigen in mice. The alpha-gal epitope (Gal alpha 1-3Gal beta 1-4GlcNAc-R) is an autoantigen, abundantly expressed in wild type mice, but absent in alpha 1,3galactosyltransferase knock-out (KO) mice, where it can induce the production of the anti-Gal antibody. Hybridoma clones secreting anti-Gal were isolated from different mice and their immunoglobulin genes were analyzed.

Analysis of autoimmune bone marrow by antibody-phage display: somatic mutations and third complementarity-determining region arginines in anti-DNA gamma and kappa V genes.

Objective: To examine anti-double-stranded DNA (anti-dsDNA) IgG autoantibodies from the bone marrow of individuals with systemic lupus erythematosus (SLE).

Methods: A library of single-chain variable fragments (scFv) was constructed from SLE bone marrow complementary DNA of gamma, kappa, and lambda isotype by cloning into the pHENIX phagemid vector. The library was screened with dsDNA in solution, and 2 anti-DNA phage, DNA1 and DNA4, were isolated and their Ig V genes sequenced.

Tandem affinity tags for the purification of bivalent anti-DNA single-chain Fv expressed in Escherichia coli.

Antibodies to DNA define an important autospecificity that arises in systemic lupus erythematosus (SLE). To elucidate the molecular features that may explain the pathogenesis of SLE, a heterologous system for expression of cloned V genes is often desirable. Here, a single-chain Fv coding domain was constructed by using the heavy- and light-chain V genes of a high-affinity site-directed mutant of the murine anti-dsDNA autoantibody, 3H9.