Yi Yuan Yang

Immunologic variables in acute mania of bipolar disorder

Macrophages, lymphocytes and their products, may be involved in the pathophysiology of psychiatric disorders. The cell-mediated immune activation response of manic patients during pre-medication and medication stages remains unclear. The purpose of this case-control study was to investigate the plasma levels of immunologic variables, including interleukin (IL)-1 receptor antagonist (IL-1RA), soluble CD 4 (sCD4) and sCD8, and TH1 (interferon [IFN]-gamma and IL-2) and TH2 (IL-4 and IL-10) cytokines in patients with pre-medicated, medicated bipolar mania. The study subjects, aged 16-44 years, were physically healthy patients with Young Mania Rating Scale (YMRS) scores > or =26, and normal controls, aged 19-40 years, were matched for sex. The immune variables were measured in acute mania and in consequent remission (YMRS scores < or =12) among bipolar patients. The plasma levels of IL-1RA, sCD4, and sCD8 were found significantly increased in pre-medicated acute manic patients as compared to normal controls. But only IL-1RA and sCD8 were found different in remitted bipolar patients as compared to normal controls. For TH1 cytokines, culture supernatant level of IFN-gamma was found significantly lower in manic patients of both acute and remission stages as compared to normal controls. No significant difference was found in IL-2 level in pre-medicated acute manic patients compared to controls. For TH2 cytokines, no significant differences in IL-4 and IL-10 levels were observed. We showed that cell-mediated immune response was activated in patients with bipolar disorder during the pre-medication, medication, and the remission stages. Our study findings suggest that the immune-modulation in patients with bipolar disorder may be abnormal.

Activation of indices of cell-mediated immunity in bipolar mania.

BACKGROUND Evidence supports that macrophages as well as lymphocytes and their products may be involved in the pathophysiology of psychiatric disorders. Whether patients with bipolar disorder have activation or reduction of immunity during a manic episode remains unclear. METHODS The purpose of this case-control study was to investigate the lymphocyte proliferation to phytohemagglutinin (PHA), concanavalin A, and pokeweed mitogen, and plasma levels of soluble interleukin-2 receptor (sIL-2R) and sIL-6R in patients with bipolar mania (DSM-III-R). The subjects were 23 physically healthy patients with Young Mania Rating Scale (YMRS) scores > or = 26 as well as aged < or = 45 years and 23 age- and gender-matched normal control subjects. The above immune variables were measured in acute mania and consequent remission (YMRS scores < or = 12) among bipolar patients. RESULTS The lymphocyte proliferation to PHA and the plasma sIL-2R levels, but not sIL-6R, of bipolar patients were significantly higher in acute mania than in consequent remission. These elevations were not due to differences in medication status. Only in acute mania were the plasma sIL-2R levels of patients significantly higher than control subjects. A positive correlation between the changes of manic severity and plasma sIL-2R levels was observed. Remitted bipolar patients and normal control subjects did not differ in any of these measures. CONCLUSIONS Cell-mediated immunity activation in bipolar mania was demonstrated and may be through a specifically state-dependent immune response.

The epigenetic effects of amyloid-β1-40 on global DNA and neprilysin genes in murine cerebral endothelial cells

Amyloid-beta (Abeta) is the core component of senile plaques, which are the pathological markers for Alzheimers disease and cerebral amyloid angiopathy. DNA methylation/demethylation plays a crucial role in gene regulation and could also be responsible for presentation of senescence. Oxidative stress, which may be induced by Abeta, is thought to be an important contributor of DNA hyper-methylation; however, contradicting this is the fact that global DNA hypo-methylation has been found in aging brains. It therefore remains largely unknown as to whether Abeta does in fact cause DNA methylation/demethylation. Neprilysin (NEP) is one of the enzymes responsible for Abeta degradation, with its expression decreasing in both Alzheimer and aging brains. Using high-performance liquid chromatography (HPLC), we explore whether Abeta is responsible for alteration of the global DNA methylation status on a murine cerebral endothelial cells model, and also use methylation-specific PCR (MSPCR) to examine whether DNA methylation status is altered on the NEP promoter region. We find that Abeta reduces global DNA methylation whilst increasing NEP DNA methylation and further suppressing the NEP expression in mRNA and protein levels. Our results support that Abeta induces epigenetic effects, implying that DNA methylation may be part of a vicious cycle involving the reduction in NEP expression along with a resultant increase in Abeta accumulation, and that Abeta may induce global DNA hypo-methylation.

Effects of symptomatic severity on elevation of plasma soluble interleukin-2 receptor in bipolar mania

BACKGROUND Circulating soluble interleukin-2 receptors (sIL-2Rs) and soluble interleukin-6 receptors (sIL-6Rs) are stable immune measures. Elevated plasma sIL-2R levels are present in patients with schizophrenia, major depression, and bipolar mania, but not with minor psychiatric disorders. The increased plasma sIL-2R levels are state-dependent in bipolar mania. However, altered production of plasma sIL-6R and the effects of clinical characteristics on plasma sIL-6R and sIL-2R levels in bipolar disorder remains uncertain. METHODS Plasma sIL-2R and sIL-6R levels were measured in 31 Taiwanese bipolar manic (DSM-IV) patients with Young Mania Rating Scale (YMRS) scores of > or =26 as well as during the subsequent remission (YMRS< or =12), and equal numbers of age- and gender-matched healthy controls. The relationships of clinical variables such as age, age of onset, smoking, medication status, coexisting psychotic features, number of prior episodes, duration of illness, presence of depression before or following the manic episode, and manic severity to plasma sIL-2R and sIL-6R levels in acute mania along with remission were examined. RESULTS Plasma sIL-2R but not sIL-6R levels were significantly higher in acute mania than in subsequent remission (P<0.05) and controls (P<0.0005). In acute mania, the plasma sIL-2R levels were significantly correlated to YMRS scores (r=0.34, P<0.05). The remaining clinical variables had no effect on plasma sIL-2R and sIL-6R levels in acute mania or remission. There was a significantly positive relationship between the reduction of plasma sIL-2R levels from the acute to follow-up measurements (DeltasIL-2R) and symptomatic improvement of acute mania (DeltaYMRS) (r=0.61, P<0.001). LIMITATIONS Our sample included medicated and unmedicated patients in acute mania. The psychotropic medication may have divergent effects on the plasma sIL-2R levels in acute mania and subsequent remission. CONCLUSIONS Elevation of plasma sIL-2R but not sIL-6R levels in bipolar mania supports the idea that the immunomodulatory mechanism may vary in different psychotic disorders. In contrast to being a trait marker in schizophrenia and depressive disorder, plasma sIL-2R levels may be considered a biological indicator of manic severity in a group of bipolar affective patients.

Antitumor Activity of Capsaicin on Human Colon Cancer Cells in Vitro and Colo 205 Tumor Xenografts in Vivo

Capsaicin was reported to inhibit cancer cell growth. The aim of this study was to evaluate the antitumor potential of capsaicin by studying antitumor activity in vitro as well as in vivo. The in vitro studies are to examine the effects of capsaicin on human colon cancer colo 205 cells after exposure to capsaicin. The results showed that capsaicin induced cytotoxic effects in a time- and dose-dependent manner and increased reactive oxygen species (ROS) and Ca(2+) but decreased the level of mitochondrial membrane potential (ΔΨ(m)) in colo 205 cells. Data from Western blotting analysis indicated that the levels of Fas, cytochrome c, and caspases were increased, leading to cell apoptosis. Capsaicin decreased the levels of anti-apoptotic proteins such as Bcl-2 and increased the levels of pro-apoptotic proteins such as Bax. Capsaicin-induced apoptosis in colo 205 cells was also done through the activations of caspase-8, -9 and -3. In vivo studies in immunodeficient nu/nu mice bearing colo 205 tumor xenografts showed that capsaicin effectively inhibited tumor growth. The potent in vitro and in vivo antitumor activities of capsaicin suggest that capsaicin might be developed for the treatment of human colon cancer.

Reduced production of interferon-gamma but not interleukin-10 in bipolar mania and subsequent remission

BACKGROUND Activation of inflammatory response system (IRS) is suggested by increased levels of plasma soluble interleukin-2 receptor (sIL-2R) in patients with bipolar mania. The reasons for changes in stimulated interferon-gamma (IFN-gamma) and interleukin-10 (IL-10) production in bipolar mania along with subsequent remission remain unclear. METHODS We measured phytohemagglutinin (PHA)-stimulated IFN-gamma and IL-10 production in 20 physically healthy inpatients aged between 18 and 45 years with bipolar mania (DSM-IV) using Young Mania Rating Scale (YMRS) scores > or = 26 and in subsequent remission (YMRS < or = 12), as well as in 15 age- and sex-matched healthy normal controls. RESULTS The mean values of IFN-gamma production in patients in acute mania and in subsequent remission were significantly lower than those of healthy controls (P=0.0004, P=0.0005, respectively). There was no significant difference in IL-10 production between bipolar patients in acute mania as well as in subsequent remission and healthy controls. In acute mania, the mean values of IFN-gamma and IL-10 production in medicated patients (n = 13) did not differ from those of drug-free patients (n = 7). Other clinical variables had no effect on IFN-gamma and IL-10 production. LIMITATION The uncontrolled medication, small sample size of the bipolar individuals, and some immune re-measurements prior to full remission periods, limit generalization from the data in this study. CONCLUSION Reduced production of IFN-gamma without alternation of IL-10 in bipolar mania and subsequent remission suggest that the immune modulation may vary in patients with different major psychiatric disorders.

Modulation of the development of human monocyte-derived dendritic cells by lithium chloride.

Lithium has been used or explored to treat psychiatric and neurodegenerative diseases that are frequently associated with an abnormal immune status. It is likely that lithium may work through modulation of immune responses in these patients. Because dendritic cells (DC) play a central role in regulating immune responses, this study investigated the influence of lithium chloride (LiCl) on the development and function of DC. Exposure to LiCl during the differentiation of human monocyte‐derived immature DCs (iDC) enhances CD86 and CD83 expression and increases the production of IL‐1β, IL‐6, IL‐8, IL‐10, and TNF‐α. However, the presence of LiCl during LPS‐induced maturation of iDC has the opposite effect. During iDC differentiation, LiCl suppresses the activity of glycogen synthase kinase (GSK)‐3β, and activates PI3K and MEK. In addition, LiCl activates peroxisome proliferator‐activated receptor γ (PPARγ) during iDC differentiation, a pathway not described before. Each of these signaling pathways appears to have distinct impact on the differentiating iDC. The enhanced CD86 expression by LiCl involves the PI3K/AKT and GSK‐3β pathway. LiCl modulates the expression of CD83 in iDC mainly through MEK/ERK, PI3K/AKT, and PPARγ pathways, while the increased production of IL‐1β and TNF‐α mainly involves the MEK/ERK pathway. The effect of LiCl on IL‐6/IL‐8/IL‐10 secretion in iDC is mediated through inhibition of GSK‐3β. We have also demonstrated that PPARγ is downstream of GSK‐3β and is responsible for the LiCl‐mediated modulation of CD86/83 and CD1 expression, but not IL‐6/8/10 secretion. The combined influence of these molecular signaling pathways may account for certain clinical effect of lithium. J. Cell. Physiol. 226: 424–433, 2011.

OmpA Is the Critical Component for Escherichia coli Invasion-Induced Astrocyte Activation

Escherichia coli is the major Gram-negative bacterial pathogen in neonatal meningitis. Outer membrane protein A (OmpA) is a conserved major protein in the E. coli outer membrane and is involved in several host-cell interactions. To characterize the role of OmpA in the invasion of astrocytes by E. coli, we investigated OmpA-positive and OmpA-negative E. coli strains. Outer membrane protein A+ E44, E105, and E109 strains adhered to and invaded C6 glioma cells 10- to 15-fold more efficiently than OmpA-negative strains. Actin rearrangement, protein tyrosine kinase, and phosphoinositide 3-kinase activation were required for OmpA-mediated invasion by E. coli. In vitro infection of C6 cells and intracerebral injection into mice of the E44 strain induced expression of the astrocyte differentiation marker glial fibrillary acidic protein and the inflammatory mediators cyclooxygenase 2 and nitric oxide synthase 2. After intracerebral infection with E44, all C57BL/6 mice died within 36hours, whereas 80% of mice injected with E44 premixed with recombinant OmpA protein survived. Astrocyte activation and neutrophil infiltration were reduced in brain tissue sections in the mice given OmpA. Taken together, these data suggest that OmpA-mediated invasion plays an important role in the early stage of E.coli-induced brain damage, and that it may have therapeutic use in E. coli meningitis.

A dominant antigenic epitope on SARS-CoV spike protein identified by an avian single-chain variable fragment (scFv)-expressing phage

Abstract Severe acute respiratory syndrome (SARS) is a newly emergent human disease, which requires rapid diagnosis and effective therapy. Among antibody sources, immunoglobulin Y (IgY) is the major antibody found in chicken eggs and can be used as an alternative to mammalian antibodies normally used in research and immunotherapy. In this study, phage-expressing chicken monoclonal scFv antibody was chosen and characterized with phage display antibody technology. Truncated fragments of SARS-CoV spike protein were cloned in pET-21 vector and expressed in BL-21 Escherichia coli (E. coli) cells. After purification, the purity of these recombinant spike proteins was examined on SDS–PAGE and their identity verified with Western blot analysis using anti-his antibodies and sera from convalescent stage SARS-CoV-infected patients. Using these bacteria-derived proteins to immunize chickens, it was found that polyclonal IgY antibodies in the egg yolk and sera were highly reactive to the immunogens, as shown by Western blot and immunocytochemical staining analysis. A phage displaying scFv library was also established from spleen B cells of immunized chicken with 5×107 clones. After four panning cycles, the eluted phage titer showed a 10-fold increase. In sequence analysis with chicken germline gene, five phage clones reacted, with large dissimilarities of between 31 and 62%, in the complementarity-determining regions, one dominant phage 4S1 had strong binding to fragment Se-e, located between amino acid residues 456–650 of the spike protein and this particular phage had significantly strong binding to SARS-CoV-infected Vero E6 cells. Based on the results, we conclude that generating specific scFv-expressing phage binders with the phage display system can be successfully achieved and that this knowledge can be applied in clinical or academic research.

Possible presence of enhancing antibodies in idiopathic thrombocytopenic purpura

It is difficult to detect IgG anti‐platelet autoantibodies in idiopathic thrombocytopenic purpura (ITP). Recently, it was reported that reactivity with glycoprotein IIb/IIIa was lost when IgG anti‐GPIIb/IIIa antibodies from seven ITP patients were digested with pepsin to yield F(ab′)2 fragments. These findings suggested that some IgG anti‐platelet autoantibodies in ITP may be of low affinity and thus require the presence of ‘enhancing’ anti‐IgG antibodies (i.e. rheumatoid factors, RFs) for detection. To test this hypothesis, we used a phage display technique to isolate five IgG RFs from an ITP patient (patient 1). Sequence analysis revealed that these RFs consisted of two clones, represented by GG3 and GG48. Both representative RFs bound specifically to IgG Fc fragments with apparent dissociation constants of 8.2 × 10−8 m and 8.8 × 10−7 m, respectively. Moreover, IgG RFs were subsequently found in a serum sample from patient 1. Combined, these results suggest that IgG RFs may occur in ITP, and may be required for the detection of some IgG anti‐platelet autoantibodies and for the corresponding antibody‐mediated platelet destruction in autoimmune ITP.