Investigations to Enterococcus faecalis as possible factor for etiology of amyloid arthropathy of brown layers

Inhaltsverzeichnis Titelblatt, Inhaltsverzeichnis 1\. Einleitung 2\. Literaturübersicht 3\. Material und Methoden 4\. Ergebnisse 5\. Diskussion 6\. Schlussfolgerungen 7\. Zusammenfassung und Summary 8\. Literaturverzeichnis 9\. AnhangIm Rahmen der vorliegenden Arbeit wurden Untersuchungen zur Charakterisierung von E. faecalis-Isolaten, die vom Haushuhn isoliert worden waren, durchgeführt. Die Charakterisierung erfolgte an 58 Feld-Isolaten zum einen über die Feststellung der Stoffwechselparameter mit dem api20 Strep-Test, zum anderen über die Serotypisierung mittels der Agargelpräzipitation und durch die Auftrennung der Restriktionsmuster mit der Pulsfeld-Gelelektrophorese. Es konnten Gruppierungen der Isolate mit jeder Methode festgestellt werden. Zwischen den Gruppierungen der Charakterisierungsmethoden konnte keine Korrelation gefunden werden. Darüber hinaus wurde der Grad der Pathogenität von E. faecalis-Isolaten durch Versuche im Brutei und im Versuchstier festgestellt. Die Ergebnisse belegen unterschiedliche Pathogenitätsgrade zwischen den Isolaten. Mit zwei Isolaten gelang die Übertragung der Ergebnisse im Brutei auf das Versuchstier. Es wurde eine Korrelation zwischen den Restriktionsmustern der genetisch nah verwandten Isolate der Gruppe A in der PFGE und dem Grad der Pathogenität festgestellt. Bei der Erstellung von Antibiogrammen konnten Resistenzen gegen verschiedene Antibiotika, v.a. gegen Streptomycin, nachgewiesen werden. Alle untersuchten Isolate erwiesen sich als empfindlich gegen Vancomycin. Für die diagnostische serologische Untersuchung von Hühnerseren wird die Spezifität eines indirekten ELISA zum Nachweis von Antikörpern gegen E. faecalis nachgewiesen und die Reproduzierbarkeit der Ergebnisse durch die Intraassay- und Interassay-Differenzen belegt. Desweiteren kann eine hohe Lagerfähigkeit der Testplatten bei 4°C, -20°C und -70°C über mindestens 18 Wochen nachgewiesen werden. Die serologischen Verlaufsuntersuchungen bei zwei Legehennenherden im Verlauf von 50 Lebenswochen ergab einen deutlichen Anstieg der Antikörperwerte im Serum mit zunehmendem Alter der Tiere ohne Anzeichen einer klinischen Erkrankung durch E. faecalis bei diesen Tieren. Diese Beobachtungen werden durch diagnostische serologische Untersuchungen bei Legehennenherden in Niedersachsen bestätigt. Auch bei diesen Herden sind höhere Antikörperwerte im Serum bei älteren Herden und niedrigere Antikörperwerte im Serum bei jüngeren Herden zu beobachten.In the present study investigations for characterization of E. faecalis isolates from chicken were described. 58 isolates from the field were characterized. Beside biochemical test of metabolism with the api20 Strep-Kit, the serotyping with the AGP and analysis of DNA restriction pattern with the PFGE were carried out. Groups of isolates could be found with each method. Comparing these groups no correlation was found. In addition, the pathogenicity of E. faecalis isolates was tested in embryonated chicken eggs and 6 weeks old chicks. The results showed differences in the pathogenicity of the isolates. The results obtained of two isolates using chicken embryo were confirmed by using two isolates after experimental infection of 6 weeks old chicks. The pattern of DNA restriction fragments in isolates from the genetic similar group A showed a correlation to the pathogenicity of these isolates. The sensibility of isolates for different antibiotics was investigated. Most of the isolates showed resistances for aminoglycosides. Against vancomycine all tested isolates were sensitive. For diagnostical serological investigations of chicken sera the specifity and reproducibility of a selfmade indirect ELISA to detect antibodies against E. faecalis was proved. The results showed no significant differences within a test plate (intraassay difference) and between different plates at different days (interassay diference). A storage period of at least 18 weeks at different temperatures (4°C, -20°C and -70°C) did not negatively influenced the results. Serological investigation in two layer flocks over a period of 50 weeks showed an increase of antibodies against E. faecalis in sera of older chickens which are not accompaned with clinical signs. These observations were confirmed by diagnostical serological investigations in layers from Lower Saxony. In these stocks of layers higher values of antibodies in sera of older layers and lower values of antibodies in sera of younger birds were observed

Prophylactic inhibition of soluble epoxide hydrolase delays onset of nephritis and ameliorates kidney damage in NZB/W F1 mice

Epoxy-fatty-acids (EpFAs), cytochrome P450 dependent arachidonic acid derivatives, have been suggested to have anti-inflammatory properties, though their effects on autoimmune diseases like systemic lupus erythematosus (SLE) have yet to be investigated. We assessed the influence of EpFAs and their metabolites in lupus prone NZB/W F1 mice by pharmacological inhibition of soluble epoxide hydrolase (sEH, EPHX2). The sEH inhibitor 1770 was administered to lupus prone NZB/W F1 mice in a prophylactic and a therapeutic setting. Prophylactic inhibition of sEH significantly improved survival and reduced proteinuria. By contrast, sEH inhibitor-treated nephritic mice had no survival benefit; however, histological changes were reduced when compared to controls. In humans, urinary EpFA levels were significantly different in 47 SLE patients when compared to 10 healthy controls. Gene expression of EPHX2 was significantly reduced in the kidneys of both NZB/W F1 mice and lupus nephritis (LN) patients. Correlation of EpFAs with SLE disease activity and reduced renal EPHX gene expression in LN suggest roles for these components in human disease

A CD2AP mutation associated with focal segmental glomerulosclerosis in young adulthood

Mutations in CD2-associated protein (CD2AP) have been identified in patients with focal segmental glomerulosclerosis (FSGS); however, reports of CD2AP mutations remain scarce. We performed Sanger sequencing in a patient with steroid-resistant FSGS and identified a heterozygous CD2AP mutation (p.T374A, c.1120 A > G). Our patient displayed mild cognitive decline, a phenotypic characteristic not previously associated with CD2AP-associated FSGS. His proteinuria was remarkably reduced by treatment with cyclosporine A. Our findings expand the genetic spectrum of CD2AP-associated disorders and broaden the associated phenotype with the co-occurrence of cognitive decline. Our case shows that cyclosporin A is a treatment option for CD2AP-associated nephropathy

Predictors of graft survival at diagnosis of antibody‐mediated renal allograft rejection: a retrospective single‐center cohort study

Antibody-mediated rejection (ABMR) is a major cause of graft loss in renal transplantation. We assessed the predictive value of clinical, pathological, and immunological parameters at diagnosis for graft survival. We investigated 54 consecutive patients with biopsy-proven ABMR. Patients were treated according to our current standard regimen followed by triple maintenance immunosuppression. Patient characteristics, renal function, and HLA antibody status at diagnosis, baseline biopsy results, and immunosuppressive treatment were recorded. The risk of graft loss at 24 months after diagnosis and the eGFR slope were assessed. Multivariate analysis showed that eGFR at diagnosis and chronic glomerulopathy independently predict graft loss (HR 0.94; P = 0.018 and HR 1.57; P = 0.045) and eGFR slope (beta 0.46; P < 0.001). Cyclophosphamide treatment (6x 15 mg/m²) plus high-dose intravenous immunoglobulins (IVIG) (1.5 g/kg) was superior compared with single-dose rituximab (1x 500 mg) plus low-dose IVIG (30 g) (HR 0.10; P = 0.008 and beta 10.70; P = 0.017) and one cycle of bortezomib (4x 1.3 mg/m(2)) plus low-dose IVIG (HR 0.16; P = 0.049 and beta 11.21; P = 0.010) regarding the risk of graft loss and the eGFR slope. In conclusion, renal function at diagnosis and histopathological signs of chronic ABMR seem to predict graft survival independent of the applied treatment regimen. Stepwise modifications of the treatment regimen may help to improve outcome

The relationship between proteinuria and allograft survival in patients with transplant glomerulopathy: a retrospective single‐center cohort study

Proteinuria and transplant glomerulopathy (TG) are common in kidney transplantation. To date, there is limited knowledge regarding proteinuria in different types of TG and its relationship to allograft survival. A retrospective cohort analysis of TG patients from indication biopsies was performed to investigate the relationship of proteinuria, histology, and graft survival. One hundred and seven (57.5%) out of 186 TG patients lost their grafts with a median survival of 14 [95% confidence interval (CI) 10-22] months after diagnosis. Proteinuria ≥ 1 g/24 h at the time of biopsy was detected in 87 patients (46.8%) and the median of proteinuria was 0.89 (range 0.05-6.90) g/24 h. TG patients with proteinuria ≥ 1 g/24 h had worse 5-year graft survival (29.9% vs. 53.5%, P = 0.001) compared with proteinuria <1 g/24 h. Proteinuria was associated with graft loss in univariable Cox regression [hazard ratio (HR) 1.25, 95% CI, 1.11-1.41, P < 0.001], and in multivariable analysis (adjusted HR 1.26, 95% CI 1.11-1.42, P < 0.001) independent of other risk factors including creatinine at biopsy, positive C4d, history of rejection, and Banff lesion score mesangial matrix expansion. In this cohort of TG patients, proteinuria at indication biopsy is common and associated with a higher proportion of graft loss

Host Defense against Viral Infection Involves Interferon Mediated Down-Regulation of Sterol Biosynthesis

Upon infection, our immune cells produce a small protein called interferon, which in turn signals a protective response through a series of biochemical reactions that involves lowering the cells' ability to make cholesterol by targeting a gene essential for controlling the pathway for cholesterol metabolism

Myeloperoxidase induces monocyte migration and activation after acute myocardial infarction

IntroductionMyocardial infarction (MI) is a significant contributor to morbidity and mortality worldwide. Many individuals who survive the acute event continue to experience heart failure (HF), with inflammatory and healing processes post-MI playing a pivotal role. Polymorphonuclear neutrophils (PMN) and monocytes infiltrate the infarcted area, where PMN release high amounts of the heme enzyme myeloperoxidase (MPO). MPO has numerous inflammatory properties and MPO plasma levels are correlated with prognosis and severity of MI. While studies have focused on MPO inhibition and controlling PMN infiltration into the infarcted tissue, less is known on MPO’s role in monocyte function.Methods and resultsHere, we combined human data with mouse and cell studies to examine the role of MPO on monocyte activation and migration. We revealed a correlation between plasma MPO levels and monocyte activation in a patient study. Using a mouse model of MI, we demonstrated that MPO deficiency led to an increase in splenic monocytes and a decrease in cardiac monocytes compared to wildtype mice (WT). In vitro studies further showed that MPO induces monocyte migration, with upregulation of the chemokine receptor CCR2 and upregulation of inflammatory pathways identified as underlying mechanisms.ConclusionTaken together, we identify MPO as a pro-inflammatory mediator of splenic monocyte recruitment and activation post-MI and provide mechanistic insight for novel therapeutic strategies after ischemic injury