Quercetin Alleviates Asthma-Induced Airway Inflammation and Remodeling through Downregulating Periostin via Blocking TGF-ß1/Smad Pathway.

INTRODUCTION: The aim of the study was to discuss whether the anti-asthmatic effect of quercetin is related to periostin and the downstream molecular pathway of quercetin's anti-asthmatic effect. METHODS: We constructed asthmatic mice, sensitized by ovalbumin, and administrated different treatments into mice according to the experimental design. In this study, we mainly observed the inflammatory response, airway fibrosis, and airway hyperresponsiveness in asthmatic mice. Pathological stains (H&E, PAS, and Masson) were performed. We also detected the inflammation factors and fibrosis-related cytokines by enzyme-linked immunosorbent serologic assay. In addition, we also explored the level of periostin by enzyme-linked immunosorbent serologic assay and Western blot. At the same time, TGF-ß1/Smad pathway was also determined by Western blot. RESULTS: A high expression of periostin was found in asthmatic mice, and quercetin decreases periostin content in bronchoalveolar lavage fluid. Quercetin and OC-20 inhibit airway inflammation response, airway fibrosis, and airway hyperreactivity. Quercetin downregulated TGF-ß1/Smad pathway in the lung tissues of asthmatic mice. Anti-asthma role of quercetin is related to periostin. Then deeper mechanical study revealed that inhibiting TGF-ß1 could improve asthmatic symptoms, and quercetin exerted the protective effect on asthmatic mice through inhibition of TGF-ß1/Smad pathway. CONCLUSION: Quercetin provided a protective role against asthma via periostin, manifested by mild inflammatory infiltration, reduced goblet cell proliferation, and reduced airway fibrosis. TGF-ß1/Smad pathway is an important transduction system, participating in the protective effect of quercetin on asthma.

Isolation of the receptor for IgG from a human monocyte cell line (U937) and from human peripheral blood monocytes.

The Fc receptors for IgG from a human monocyte line (U937) and from highly purified human peripheral blood monocytes were solubilized, purified, and partially characterized. Both sources of cells gave indistinguishable results. Two molecules (or sets of molecules), one of about 72,000 mol wt and the other of 40,000-43,000 mol wt were discerned on autoradiograms of sodium dodecyl sulfate (SDS)-polyacrylamide gels analyzing acid eluates from Sepharose-IgG columns over which detergent lysates of radioiodinated cells had been passed. The larger of the two molecules, p72, accounted for greater than or equal to 90% of the radioactivity. This component was noted to be heterodisperse both by size on SDS gels and by charge on isoelectric focusing gels. The charge heterogeneity, being virtually eliminated by neuraminidase and tunicamycin, was probably due to variable glycosylation. Several lines of evidence indicated that p72 is probably all or part of the Fc receptor: (a) radiolabeling of this molecule using chloroglycouril was blocked by IgG of the Fc receptor; (b) in soluble form this molecule expressed ligand specificity identical to the in situ receptor; (c) the molecule was not recovered from affinity adsorbants bearing proteins that do not bind to the Fc receptors, nor (d) from a human T cell line that does not bear Fc receptors. The smaller of the two molecules isolated, p40-43, is at least in part actin. Its relationship to p72 is not understood.

The specificity of T-cell helper factor in man.

Supernates of human T cells stimulated with TT antigen contain a factor that induces mitogenesis and immunoglobulin synthesis in autologous as well as allogeneic B cells. A fraction of the IgG produced has specificity against TT. The T-cell-derived LMF-TT eluted after albumin on Sephadex G 200 and did not contain immunoglobulin heavy chain determinants. LMF-TT was active on B cells from TT immune as well as TT- nonimmune individuals but in the latter instance the IgG secreted had no specificity against TT. B cells incubated with LMF-TT in the presence of a second antigen (DT) made IgG with specifity to that antigen provided the B-cell donor was immune to that second antigen. LMF-TT-containing supernates were depleted of TT antigen by Sephadex G 200 chromatography followed by passage over anti-TT immunosorbent columns. The antigen-free supernates were able to induce mitogenesis and IgG synthesis in B cells but the IgG produced failed to exhibit specificity against TT unless the TT antigen was readded to the B-cell cultures. The optimal concentration of LMF-TT (50 percent) inducing B-cell mitogenesis was different from the optimal concentration (20 percent) causing IgG synthesis by B cells. At low LMF concentrations (less than or equal 10 percent) addition of a second antigen to which the cell donor was immune caused an increase in the degree of B-cell mitogenesis. Submitogenic concentrations of LMF-TT (less than or equal to 5 percent) were still capable of inducingimmunoglobulin synthesis in B cells At these low concentrations of LMF-TT the proportion of anti-TT IgG over total IgG increased sharply. B cells from TT immune donors were separated on TT immunosorbent columns. Cells that bound to the column were more sensitive to the mitogenic and IgG synthetic effects of LMF-TT than unfractionated B cells. Thus, LMF is a nonspecific human T-cell helper factor which behaves like a polyclonal B-cell activator. However, in the presence of specific antigen (TT) the antigen-specific B cell is preferentially triggered by LMF. The experimental design of the present study does not rule out the additional presence of an antigen-specific helper factor in the supernates of TT-stimulated human T cells.

Allosensitization of islet allograft recipients.

BACKGROUND: The immune monitoring of islet transplant recipients includes the assessment of panel reactive antibodies (PRA). A negative association of PRA+ with allogeneic solid organ graft survival has been recognized, but scattered data is available for islet transplantation. METHODS: We performed a retrospective analysis of PRA status in 66 patients with type 1 diabetes mellitus recipient of islet allografts between 1985 and 2006. RESULTS: Pretransplant PRA+ was observed in 10 subjects in the old trials and associated with kidney transplantation and/or pregnancies. Thirteen subjects displayed PRA+ at follow-up, eight of whom were de novo. Overall, PRA+ did not correlate with islet graft outcome: long-term graft survival was observed in the presence of basal or persistent PRA+ and graft dysfunction occurred also in the absence of PRA+. Loss of graft function was associated with PRA+ after lowering of immunosuppression or after infection episodes. Loss of C-peptide did not affect kidney graft function even in simultaneous islet-kidney transplant recipients. Mostly, PRA remained negative under adequate immunosuppression. Patients whose immunosuppression was discontinued invariably developed PRA+. CONCLUSIONS: Monitoring of PRA under immunosuppression may have little clinical value under adequate immunosuppression in islet transplant recipients. The implications of allosensitization after discontinuation of immunosuppression need to be evaluated to define the real clinical impact in this patient population.

Extracellular domains of the beta, gamma and epsilon subunits of the human acetylcholine receptor as immunoadsorbents for myasthenic autoantibodies: a combination of immunoadsorbents results in increased efficiency.

Myasthenia gravis (MG) is usually caused by autoantibodies against the human muscle acetylcholine receptor (AChR). Plasmapheresis offers a therapeutic option, but, as well as removing the pathogenic anti-AChR autoantibodies, it non-specifically removes indispensable immunoglobulins. An attractive alternative to plasmapheresis would be the extracorporeal specific removal of the autoantibodies using AChR-based immunoadsorbents. Previously, we used the N-terminal extracellular domain (ECD) of the AChR alpha subunit to immunoadsorb anti-alpha subunit autoantibodies from MG sera. In this study, we immobilised the beta -, gamma- and epsilon-AChR ECDs on Sepharose and tested them as immunoadsorbents on 50 MG sera. A given ECD removed a different percentage of autoantibodies from different sera and different ECDs removed different percentages from the same serum; on average, the beta-, gamma- and epsilon-ECDs removed 22%, 20% and 15.5% of the autoantibodies, respectively. Immunoadsorption was completed in 3 min, 1 mug of ECD removed approximately 2 pmol of autoantibodies, and the immunoadsorbent could be recycled approximately 4 times. The combined use of two (alpha+gamma) or four (alpha+beta+gamma+epsilon) ECDs in a single immunoadsorbent resulted in much higher (often additive) immunoadsorption. These results show that MG sera have autoantibodies against several AChR subunits, and suggest that the combined use of all AChR ECDs could provide the basis for a novel, antigen-specific therapy for MG.

A quantitative assay for Epstein-Barr Virus-specific immunity shows interferon-gamma producing CD8+ T cells increase during immunosuppression reduction to treat posttransplant lymphoproliferative disease.

Reduction of immunosuppression (RIS) to allow development or recovery of Epstein-Barr virus (EBV) immunity can be used to treat EBV-associated posttransplant lymphoproliferative disease (PTLD). Quantification of EBV-specific immunity would help assessment of the efficacy of RIS therapy. Use of intracellular cytokine staining and analysis by flow cytometry to monitor functional EBV-specific T-cell immunity was evaluated in healthy volunteers. The technique was then used to monitor EBV immunity in nine renal transplant patients with PTLD during RIS. The number of interferon (IFN)-gamma producing CD8+ T cells specific for EBV increased distinctly before regression of EBV+ PTLD tumors occurred. The findings confirm the importance of IFN-gamma producing CD8+ T cells in controlling the malignant EBV-transformed B cells of PTLD. The assay effectively quantified EBV immunity during RIS in transplant patients with PTLD.

Moderate effect of enamel matrix derivative (Emdogain Gel) on Porphyromonas gingivalis growth in vitro.

OBJECTIVE: The aim of this study was to analyse the antibacterial effects of Emdogain Gel or its constituents on the growth of the suspected periodontopathogen Porphyromonas gingivalis. STUDY DESIGN: The effects of the proteins of enamel matrix derivative (EMD), the commercial product Emdogain Gel or its vehicle propylene glycol alginate (PGA) (Straumann, Switzerland) on P. gingivalis growth were determined by two methods: broth dilution assay (BDA) and agar diffusion assay (ADA). RESULTS: BDA-Emdogain Gel inhibited moderately the growth of P. gingivalis, whereas EMD showed no effect. The PGA vehicle inhibited the growth completely. ADA-Emdogain Gel resulted in some inhibition in growth but was not significantly different from control. EMD revealed no zone of inhibition. PGA demonstrated statistically significant zones of inhibition. CONCLUSION: Emdogain Gel shows moderate antibacterial activities against P. gingivalis. These properties seem to be due to the PGA component of the gel preparation.

Use of protein A immunoadsorption as a treatment for thrombocytopenia in HIV-infected homosexual men: a retrospective evaluation of 37 cases.

Thirty-seven HIV-infected homosexual men with thrombocytopenia (less than 100 x 10(9)/l) received protein A immunoadsorption treatments to remove platelet-sensitizing immunoglobulin (Ig) G and circulating immune complexes (CIC) from plasma. Patients received an average of six treatments each, consisting of 250 ml plasma over a 3-week period. Clinical improvement in hemorrhagic symptoms associated with substantial increase in platelet counts was achieved in 18 patients. These responses were maintained over a median follow-up period of more than 7 months in 14 evaluable patients who were not lost to follow-up (three patients relapsed in 2 weeks and one received another therapy). Generally, moderate transient treatment-related side-effects included fever, musculoskeletal pain, chills and nausea. A transient serum sickness-like reaction was observed in seven patients, leading to termination of treatment in two. Clinical responses were associated with significant decreases in levels of platelet-sensitizing Ig, including CIC. Stimulation of broadly cross-reactive anti-antigen-binding fragment [F(ab)2], antibodies contributed to these responses. Protein A immunoadsorption is an effective alternative treatment for HIV-associated thrombocytopenia.

Multiple sclerosis: serum gamma globulin and demyelination in organ culture.

Multiple sclerosis (MS) sera frequently demyelinate organotypic central nervous system (CNS) tissue cultures. To elucidate the possible role of gamma globulins in this form of experimental demyelination we depleted MS sera of all gamma globulins by immunoabsorption and then compared their demyelinating activity with that of the unabsorbed sera. In only 2 out of 16 patients was some demyelinating activity detected in the gamma globulin fraction. In all patients, most of the demyelinating activity was not associated with gamma globulins. In gel filtration experiments, this non-gamma globulin activity was detected in a high-molecular-weight and in a low-molecular-weight fraction.

Radioimmunoassay for hepatitis B surface antigen and antibody using a two-component immunoadsorbent.

A solid-phase radioimmunoassay is described for detection of hepatitis B surface antigen and antibody. The assay uses a two-site (antigen and antibody) immunoadsorbent capable of binding antigen and antibody. Antigen is detected by enhanced binding of [125U]antibody through sandwich formations of antibody--antigens--[125I]antibody on the immunoadsorbent. Antibody presence is revealed by inhibition of [125I]antibody binding.

Purification of antibodies to bacterial antigens by an immunoadsorbent and a method to quantify their reaction with insoluble bacterial targets.

A combination of procedures was employed to develop a radioimmunoassay which quantified the binding of antibodies to antigens of either intact Propionibacterium acnes or to antigens of insoluble extracts derived from the bacteria. Reactive antibody populations were purified by use of bacterial immunoadsorbents which were prepared by coupling P. acnes to diethylaminoethyl cellulose. Binding of antibodies was detected with [125I]staphylococcal protein A ([125I]SpA) and optimal conditions for the assay defined by varying the amounts of antibodies, bacterial antigenic targets and [125I]SpA. In antibody excess, 100% of available [125I]SpA was bound by the target-antibody complexes. However, when antibody concentration was limiting, a linear relationship was demonstrated between per cent specific binding of [125I]SpA and antibodies bound to bacterial targets. These results were achieved only with immunoadsorbent-purified antibody populations and not with hyperimmune sera or IgG. The radioimmunoassay detected subtle antigenic differences and similarities between P. acnes, P. acnes extracts and a variety of unrelated microorganisms.

A screening assay for rapid and quantitative measurement of immunoglobulins and anti-immunoglobulins in unknown sera.

A radioimmunoassay which can measure serum levels of antibody and antigen when both species are immuloglobulins (Igs) is described. The technique is based on competition between insolubilized Ig (bound to Sepharose) and serum Ig for radiolabeled Ig. For measurement of anti-Ig antibodies, labeled Ig antigen is added to a mixture of antibody-Sepharose and unknown or standard antibody solution. For measurement of antigen, labeled, purified antibody is added to a mixture of antigen-Sepharose and unknown or standard antigen solution. Although both assays can detect either Ig antigen or Ig antibody in a given unknown, the antibody assay requires 10-20 times as much antigen as antibody to achieve the same degree of inhibition, and the antigen assay is 100 times more sensitive for antigen than for antibody. By titrating the same unknown in both assays, one can determine whether inhibitory activity is due to antigen or antibody. The routine assay readily detects 1 microgram/ml of antibody or of antigen. A modified assay was also developed which detects levels of antibody as low as 5-10 ng/ml. The technique is simple and allows rapid screening of hundreds of serum samples in a short period of time. The assay can also be modified for measurement of anti-idiotype antibodies.

Some parameters of affinity chromatography in the purification of antibody against Naja naja siamensis toxin 3.

Some parameters in the purification of antibodies against Naja naja siamensis toxin 3 by affinity chromatography were studied on toxin Sepharose, toxin-succinylaminoethyl Sepharose, toxin-albumin Sepharose and toxin succinylaminoethyl Biogel adsorbents. Immunologically pure antibody with 10-12-fold increase in potency was obtained by chromatography of horse refined globulin on all these adsorbents. The maximum antibody binding capacities were higher for adsorbents containing linear spacers but represented only 7-16% of the theoretical binding capacity. The operational half-lives of the adsorbents ranged from 19 to 108 days with toxin-albumin Sepharose showing the highest stability. The recovery of neutralizing capacity was about 30-356% for any of the 4 adsorbents. It is concluded that improvements regarding the antibody binding capacity and the recovery of neutralizing capacity should be made before large scale purification of antibody for therapeutic purposes can be attempted.

Development of a cell line secreting monoclonal antibody specific for concanavalin A and use of that antibody as an affinity immunosorbent for tissue culture media used to support long-term T cell growth.

A new cell line, 71A7, secreting a monoclonal mouse IgG1 antibody specific for the protein concanavalin A (Con A) has been established. The stable and rapidly growing line has been propagated in vitro for several months without loss of secretion of antibody. Affinity purified antibody has been used as an immunoadsorbent to remove Con A from tissue culture supernatants for long-term T cell maintenance.

The use of cellulose carbonate-based immunoadsorbents in the isolation of minor allotypic components of rabbit immunoglobulin populations.

Cellulose trans-2,3-carbonate has been used as a new insoluble matrix for the simple coupling of a1- and b4-positive rabbit immunoglobulin to make immunoadsorbents capable of purifying from serum, with great efficiency, alloantibodies to these allotypic determinants. The antibodies have themselves been conjugated to prepare specific antibody immunoadsorbents of high binding activity for their allotypic target molecules. With these anti-allotypic solid-phase reagents it has been possible to affinity purify a1- and b4-positive immunoglobulin molecules and to deplete serum immunoglobulin of these molecules to leave in the eluates only the allotypically uncontaminated minor immunoglobulin components which are a-negative or b-negative (lambda chain-bearing) molecules. lambda chain molecules were also purified in very small quantities by affinity chromatography on a sheep anti-rabbit lambda chain column. This method of purifying minor populations of rabbit immunoglobulin from normal serum by special immunoadsorbent applications offers new opportunities to study the products of rarely expressed immunoglobulin genes in normal rabbits.

Enzyme and radioimmunoassays for specific murine IgE and IgG with different solid-phase immunosorbents.

Enzyme and radioimmunoassays of specific murine IgE and IgG were done using antigen-coated flex vinyl plates, antigen-coupled paper discs or Sepharose 4B beads as solid-phase immunosorbents. These 3 immunosorbents differ in their antibody binding capacities. Only Sepharose beads have a high capacity so that they can be used to assay specific IgE in serum samples without interference from specific IgG which can be present in concentrations of several thousand times greater than those of specific IgE. All 3 types of immunosorbents are equally useful for assaying specific IgG, but the flex vinyl plate is the immunosorbent of choice since it requires less time and gives lower blanks than do the other two. Under the conditions tried, the lowest detectable concentration of specific IgE or IgG was about 1 ng/ml on enzyme or radioimmunoassay. The immunoassays described in this paper are useful for following the kinetics of specific IgE and IgG responses in mice. This was demonstrated with sera from mice immunized with ragweed antigen E.

In vitro evaluation of the efficacy and biocompatibility of new, synthetic ABO immunoabsorbents.

Synthetic ABO immunoabsorbents (known as Synsorbs) were in use for several years to specifically eliminate ABO antibodies from the patient's circulation before ABO-incompatible organ or bone marrow transplantation. Because Synsorbs are no longer available, we have developed new ABO immunoabsorbents. These substances, termed BioSorbents A and B, respectively, consist of synthetic A or B trisaccharides covalently coupled to macroporous glass beads via polyacrylamide. Here we report the evaluation of BioSorbents in regard to efficacy, specificity, and biocompatibility. Using a closed-circuit in vitro system, representing a 1:10-1:20 scale as compared with the immunoabsorption procedure with an adult patient, blood group O plasma was run through columns filled with ethylene oxide-sterilized BioSorbent. Hemagglutination was reduced by 4 titer steps after absorption, and anti-A and/or anti-B IgM/G/A, as measured by ABO ELISA, dropped by 85% or more, while no nonspecific absorption of immunoglobulins occurred. No significant changes could be observed for complement (C3, C4, and total hemolytic complement of the classical pathway) or for coagulation parameters (fibrinogen, prothrombin time, activated partial thromboplastin time). As monitored by immunoblotting, neither factor XII nor high molecular weight kininogen was cleaved. In addition, a monocyte phagocytosis inhibition test provided evidence that no significant aggregation of IgG had occurred during absorption. We conclude that BioSorbents A and B are efficient, specific, and biocompatible with human plasma.

Factor VIII fractionation on aminohexyl Sepharose with possible reduction in hepatitis B antigen.

The method of factor VIII purification by chromatography on aminohexyl Sepharose has been extended so that up to 100 ml of intermediate purity concentrate can be processed on an 8.6 ml column. The product has a specific activity of 1.8 International Units of factor VIII per mg of protein. Most of the fibrinogen is removed and antibodies to blood group substances A and B are not detectable by haemagglutination techniques. Hepatitis B antigen has been reduced to one sixteenth of that in the starting material, in preliminary experiments. The process has the added advantage that it concentrates the factor VIII relative to the starting material.

An alternative method of panning for rat B lymphocytes.

A new method of panning for B lymphocytes is described in which the ability of the sIg+ cells to adhere depends on the nature and concentration of nonspecific protein used rather than on the use of anti-immunoglobulin. Rat lymph node cells were suspended in 3% bovine serum albumin in Tris-buffered Hanks' and incubated in tissue culture flasks to allow adherence to the plastic. The recovered bed of adherent cells was shown by flow cytometry to be greater than 90% surface immunoglobulin positive and MHC class II positive while containing very few T cells. This adherent fraction was subsequently treated with anti-T cell antibody plus baby rabbit complement to produce a highly purified sIg+ cell population containing no detectable T cells. The sIg+ cells obtained by this panning procedure were functionally active in BCGF and BCDF assays. This method provides an easy and inexpensive alternative to conventional panning with anti-immunoglobulin and also eliminates the possibility of B cell activation by exposure to anti-immunoglobulin-coated surfaces.

Immunoadsorption, current status and future developments.

The association of abnormalities in the cellular and humoral immune system with various autoimmune diseases provides the rationale for apheresis technologies. While plasmapheresis or plasma exchange is limited by its non-selective removal of all plasma components, modern apheresis techniques aim to provide more specific elimination according to clinical needs and avoid plasma product replacement. However, the commercialisation has not met the expectations in the early 80's and the number of patients treated by extracorporeal immunoadsorption remains small due to a lack of well-defined controlled trials and limited reimbursement. This review highlights the immunological and technical basis for extracorporeal immunoadsorption, as well as its current status in the treatment of immunologically-mediated diseases.