Specific association of small heat shock proteins with the pathological hallmarks of Alzheimer's disease brains

The small heat shock protein family (sHsp) comprises molecular chaperones able to interact with incorrectly folded proteins. Alzheimer's disease (AD) is characterized by pathological lesions such as senile plaques (SPs), cerebral amyloid angiopathy (CAA) and neurofibrillary tangles (NFTs), predominantly consisting of the incorrectly folded proteins amyloid-beta (Abeta) and tau respectively. The aim of this study was to investigate the association of the chaperones Hsp20, HspB2, alphaB-crystallin and Hsp27 with the pathological lesions of AD brains. For this purpose, a panel of well-characterized antibodies directed against these sHsps was used in immunohistochemistry and immunoblotting. We observed extracellular expression of Hsp20, Hsp27 and HspB2 in classic SPs, and Hsp20 expression in diffuse SPs. In addition, extracellular expression of HspB2 was observed in CAA. Both Hsp27 and alphaB-crystallin were also observed in astrocytes associated with both SPs and CAA. Furthermore, none of the sHsps were observed in NFTs in AD brains. We conclude that specific sHsp species may be involved in the pathogenesis of either SPs or CAA in AD.     

Molecular chaperons, amyloid and preamyloid lesions in the BRI2 gene-related dementias: a morphological study

Molecular chaperons or amyloid-associated proteins (AAPs) are deposited in vascular and parenchymal amyloid lesions in Alzheimer's disease (AD) and other amyloidoses. AAPs, such as apolipoprotein E (ApoE) or apolipoprotein J (ApoJ) have been strongly implicated in the pathogenesis of AD in vitro and in vivo. Furthermore the possession of the ApoE in4 allele is a well-studied risk factor for AD. In view of the similarities between AD and both familial British dementia (FBD) and familial Danish dementia (FDD), we investigated the presence of AAPs in these two diseases to understand better their role in the general process of amyloidogenesis. Immunohistochemistry for ApoE, ApoJ, serum amyloid P (SAP), alpha-1-antichymotrypsin, cystatin C, heparan sulphate proteoglycans, such as agrin, perlecan, syndecans, glypican-1 and for heparan sulphate glycosaminoglycan (HS GAG) side chains was carried out together with immunohistochemical preparations specific to the amyloid subunits. Significant or extensive staining for ApoE, ApoJ, agrin, glypican-1 and HS GAG side chains was found in both amyloid (fibrillar) and preamyloid (nonfibrillar) deposits in FBD and FDD. The remaining AAPs, including SAP, were predominantly found in amyloid lesions. Only very weak staining was present in a small proportion of the amyloid lesions using perlecan immunohistochemistry. These findings suggest that the deposition patterns of AAPs in FBD and FDD are mostly similar to those in AD. The presence of AAPs in the preamyloid lesions supports the notion that chaperon molecules may play a role in the early steps of fibrillogenesis.     

CSF protein profiling using Multiplex Immuno-assay

Objective The diagnosis of leptomeningeal metastases (LM) is based on clinical symptoms, magnetic resonance imaging (MRI) of brain and spine and cytological analysis of cerebrospinal fluid (CSF). The clinical picture of LM is highly variable and both cytological CSF analysis and contrast-enhanced MRI are limited in sensitivity. More sensitive tools are needed to diagnose LM. We measured a profile of proteins involved in adhesion and inflammation in the CSF of LM and control patients and determined their potential diagnostic value for LM. Patients and methods Using Multiplex Immuno-Assay (MIA), the CSF concentrations of nine soluble adhesion molecules, cyto- and chemokines were measured in patients with cytologically proven LM (n=57) and control patients with a systemic malignancy (n=20), aseptic/viral meningitis (n=11) or other (non-)neurological diseases (n=19). Results We found high CSF levels of soluble Vascular Cell Adhesion Molecule-1 (sVCAM-1), soluble Intercellular Adhesion Molecule-1 (sICAM-1), Interleukin-8 (IL-8), Pulmonary and Activation Regulated Chemokine (PARC), Interleukin-18 (IL-18) and Interferon-γ inducible protein (IP-10) in patients with LM. The CSF protein profile in LM patients differed significantly from the profile found in control patients. Multivariate logistic regression and ROC analysis showed that the MIA-measured CSF protein profile has an additive discriminating value for LM above standard CSF parameters. A combination of total protein, glucose, IL-8, PARC and IP-10 CSF levels proved to be most discriminative between LM and non-LM patients. Conclusion Our results warrant a prospective study to determine whether a CSF protein profile, including IL-8, PARC and IP-10 has diagnostic value compared with CSF cytology, the golden standard for LM. Received in revised form: 2 November 2005     

Variable stress-responsiveness in wild type and domesticated fighting fish

We combined behavioral and physiological measures to compare coping style in wild-type Betta splendens and a domesticated strain selectively bred for sports fighting. We showed previously that the fighter strain is more aggressive than the wild type during experimental conditions that most closely resemble an actual fight. We predicted that compared to the wild type, the fighter strain would show a more proactive coping style, characterized by lesser cortisol and greater sympathetic responses to non-social challenges. We introduced males to an unfamiliar environment and spatial confinement as challenges that may resemble some of those that B. splendens may encounter in its natural habitat. We developed a non-invasive stress assay that enables repeated individual measures of water-borne cortisol. We estimated sympathetic activation through opercular beat rate and recorded the duration of behavioral immobility. We found that exposure to an unfamiliar environment raised cortisol levels in the wild type but not in the fighter strain and that confinement raised cortisol levels in both. In both strains opercular beat rates were significantly reduced during the latter stages of confinement compared to during the early stages. The fighter strain, but not the wild type, adopted a behavioral strategy of immobility from the very beginning of confinement.     

Decreased circulating iNKT cell numbers in refractory coeliac disease

INTRODUCTION: A small proportion of coeliac disease (CD) patients become refractory (RCD) to a gluten-free diet (GFD) showing uncontrolled immune-mediated enteropathy. Some of these patients exhibit a high risk to develop enteropathy-associated T-cell lymphoma (EATL). AIM: The aim of the study was to find whether a lack of circulating homeostatic T cells, such as Treg, Tgammadelta(+) or iNKT cells would be associated with the development of RCD or EATL. PATIENTS AND METHODS: We investigated in a total of 137 CD patients [28 untreated, 80 responsive to GFD and 29 RCD (14 type I and 15 type II)] and 73 age-matched healthy volunteers the frequency of Treg, Tgammadelta(+) and iNKT lymphocytes by flow cytometric analysis of peripheral blood. RESULTS: Circulating Tgammadelta(+) cell and Treg frequencies in RCD were comparable to those in healthy controls. However, RCD patients had significantly reduced numbers of circulating iNKT cells, as compared to age-matched patients responding to a GFD. This reduction was similar in RCD patients with and without aberrant intraepithelial lymphocytes and in patients with EATL. Circulating iNKT cell numbers were not reduced in untreated coeliac patients. GFD treated patients had a significantly increased proportion of CD4(+) iNKT cells. CONCLUSION: Follow-up studies are necessary to determine whether CD4(+) iNKT cells control the immune response against gluten and their absence contributes to the progression to RCD and EATL.     

Cardiac resynchronization therapy cures dyssynchronopathy in canine left bundle-branch block hearts.

AIMS: We investigated to what extent biventricular pacing (BVP) can normalize LV function and remodeling, induced by isolated left bundle branch block (LBBB). METHODS AND RESULTS: In 16 dogs LBBB was induced. Eight animals were followed for 16 weeks and in 8 animals BVP was started after 8 weeks. LV pressure, LV geometry (2Dechocardiography), systolic circumferential shortening (CSsys, MRI tagging) and myocardial blood flow (MBF, microspheres) was measured. * and # indicate P < 0.05 compared to pre-LBBB and 8 weeks of LBBB, respectively. Data is presented relative to pre-LBBB values (mean +/- SEM). BVP increased LV dP/dt|max from 78 +/- 5%* to 86 +/- 5%*# (immediately) and 89 +/- 6%# (after 8 weeks) and normalized regional differences in CSsys and MBF. After 8 weeks of BVP, LV end-diastolic volume (EDV) was reduced from 123 +/- 3%* to 109 +/- 6%# and LV lateral wall mass was reduced from 128 +/- 5%* to 113 +/- 3%*#. The acute increase in LV dP/dt|max upon BVP correlated with LV EDV and LV wall mass after 8 weeks of BVP. CONCLUSION: In canine hearts with long-term isolated LBBB, BVP largely reverses global and regional functional and structural abnormalities induced by LBBB.     

Role of the sialophorin (CD43) receptor in mediating influenza A virus- induced polymorphonuclear leukocyte dysfunction

Polymorphonuclear leukocytes (PMNLs) exposed to influenza A virus (IAV) undergo activation of the respiratory burst followed by depression of cell function when subsequently exposed to particulate or soluble stimuli. The effect of IAV on PMNLs is likely to be mediated through the attachment of IAV to one or more specific receptors. Recently, IAV has been shown to bind to the sialophorin protein (CD43) receptor on PMNL plasma membranes. The present study was performed to determine if the sialophorin receptor was responsible for IAV-induced PMNL dysfunction. When PMNLs were incubated with IAV or CD43 monoclonal antibody (MoAb) for 30 minutes and then exposed to a secondary particulate (opsonized zymosan) or soluble (FMLP or phorbol 12- myristate 13-acetate) stimulus, there was significant depression of the PMNL chemiluminescence response compared with the equivalent control (P < .05). When PMNL were incubated with the CD43 MoAb and then cross- linked with a goat antimouse IgG antibody, no depression of PMNL function occurred upon secondary stimulation. Exposure of cells to IAV aggregates also eliminated the PMNL dysfunction that normally occurs due to the virus. Similar to IAV, PMNL dysfunction due to the CD43 MoAb could be overcome by priming the cells with granulocyte-macrophage colony-stimulating factor. These findings indicate that IAV-induced PMNL dysfunction is mediated, at least in part, through the sialophorin receptor.     

Use of a generally applicable tissue factor--dependent factor V assay to detect activated protein C-resistant factor Va in patients receiving warfarin and in patients with a lupus anticoagulant

The original activated partial thromboplastin time-based assay for activated protein C (APC)-resistant factor Va (FVa) requires carefully prepared fresh plasma and cannot be used in patients receiving warfarin or in patients with antiphospholipid antibodies. A new test is described here that circumvents these limitations and distinguishes without overlap heterozygotes for APC-resistant FVa from persons with normal FV. A diluted test plasma is incubated with an FV-deficient substrate plasma and tissue factor and then clotted with Ca2+ or Ca2+ plus APC. Test results are independent of the FV level or the dilution of the test plasma used. Of 39 controls, 37 gave normal results. Two controls (5%) gave results indicative of APC resistant FVa and on DNA analysis were found to be heterozygous for FV R506Q. Twenty of 21 randomly selected patients receiving warfarin gave normal results. In the single patient with abnormal results, heterozygous FV R506Q was confirmed by DNA analysis. Two of 15 patients with protein S deficiency and 5 of 29 patients with a lupus anticoagulant had abnormal results. APC resistance caused by FV R506Q was confirmed in the five of these seven patients available for DNA analysis. APC-resistant FVa was also detected in 10 of 21 (46%) stored plasma from unrelated patients with venous thrombosis and negative earlier evaluation for a lupus anticoagulant or a deficiency of protein C, protein S, or antithrombin, which confirms a high incidence of this defect among patients with venous thrombosis.