Ariane Aigelsreiter

The role of liver biopsy in the diagnosis and prognosis of patients with acute deterioration of alcoholic cirrhosis

BACKGROUND & AIMS The aim of this study was to systematically assess the diagnostic and prognostic value of early liver biopsy in patients who require hospital admission with acute deterioration of alcoholic cirrhosis. METHODS Sixty-eight patients with acute deterioration of alcoholic cirrhosis underwent a liver biopsy within 7 days and the biopsies were processed using routine stains and K8/18 immunohistochemistry to characterize balloon degeneration. The biopsies were scored by two independent histopathologists using pre-defined criteria. The patients were managed according to institutional protocols and followed until the time of hospital discharge or death. RESULTS With use of K8/18 immunohistochemistry, very high concordance rate for the diagnosis of balloon degeneration was reached (r = 0.7; p = 0.0001). The presence of a systemic inflammatory response (SIRS) suggestive of acute alcoholic steatohepatitis (ASH), predicts severe ASH histologically in only 50% patients. Moreover, in 41% of SIRS negative patients who were thought not to have ASH, a diagnosis of ASH was subsequently confirmed on histological grading. Patients that have SIRS criteria but no evidence of histological ASH are more likely to develop infection which may be indicated by the severity of canalicular cholestasis. Nineteen patients died during follow up. Patients manifesting ASH on biopsy who were also SIRS positive, had a significantly greater risk of mortality compared to those that were SIRS positive but ASH negative (p < 0.01) and those that were SIRS negative (p < 0.0001). CONCLUSIONS The use of K8/18 immunostaining allows grading of the severity of alcoholic steatohepatitis. Early liver biopsy in these patients presenting with acute deterioration of cirrhosis is safe and provides important diagnostic and prognostic information.

Distinct signatures of B-cell homeostatic and activation-dependent chemokine receptors in the development and progression of extragastric MALT lymphomas†‡

Chemokine receptors mediate migration and activation of lymphocytes through binding of their ligands. Recent studies have revealed important contributions of chemokine receptors to the development, progression, and dissemination of haematopoietic neoplasms. Because the chemokine receptor expression profile in extragastric MALT lymphoma is unknown, we performed a comprehensive study on tissue samples of parotid glands, parotid glands affected by Sjögren syndrome, extragastric MALT lymphoma, and extranodal diffuse large B‐cell lymphoma (eDLBCL) originating from MALT lymphoma (transformed MALT lymphoma). By investigating the expression of 19 chemokine receptors by real‐time PCR using a semi‐quantitative approach and of four chemokine receptors (CCR1, CCR5, CXCR6, and XCR1) by immunohistochemistry, we show that the chemokine receptor expression profiles of extragastric MALT lymphomas differ substantially from those of extranodal DBLCL, with lower expression of CCR1, CCR8, and CXCR3, and the absence of expression of CX3CR1 and XCR1 in eDLBCL. Expression of CCR6, CCR7, CXCR3, CXCR4, and CXCR5, responsible for B‐cell homing to secondary lymphoid tissue, was detected in both B‐cell malignancies. Expression of CCR4 was just detected in trisomy 3‐positive MALT lymphoma cases. Comparing gastric with extragastric MALT lymphomas, up‐regulation of CXCR1 and CXCR2 accompanied by down‐regulation of CCR8 and CX3CR1 and loss of XCR1 expression in extragastric MALT lymphomas appear to be key determinants for the site of origin of MALT lymphomagenesis. Our results support a model of stepwise progression of extragastric MALT lymphoma from a non‐neoplastic event to Sjögren syndrome, to MALT lymphoma, and finally to overt eDLBCL, guided by differentially expressed B‐cell homeostatic and activation‐dependent chemokine receptors and their ligands. Copyright

Chlamydia psittaci Infection in Nongastrointestinal Extranodal MALT Lymphomas and Their Precursor Lesions

Extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT) are associated with various infectious pathogens. We analyzed the presence of Chlamydia psittaci, Chlamydia pneumoniae, and Chlamydia trachomatis DNA in 47 nongastrointestinal and 14 gastrointestinal MALT lymphomas, 37 nonmalignant control samples, and 27 autoimmune precursor lesions by polymerase chain reaction amplification and direct sequencing. In 47 nongastrointestinal MALT lymphomas, 13 (28%) were positive for C psittaci DNA compared with 4 (11%) of 37 nonmalignant control samples (P = .09). C psittaci was detected at variable frequencies in MALT lymphomas of different sites: lung, 100% (5/5; P < .01); thyroid gland, 30% (3/10; P > .05); salivary gland, 13% (2/15; P > .05); ocular adnexa, 15% (2/13); and skin, 25% (1/4). Of 27 autoimmune precursor lesions (11 Hashimoto thyroiditis and 16 Sjögren syndrome), 11 (41%) contained C psittaci DNA. Only 1 (7%) of 14 gastrointestinal MALT lymphomas was positive for C psittaci. All specimens were negative for C trachomatis and C pneumoniae. Besides ocular adnexal lymphomas, C psittaci infection is associated with nongastrointestinal MALT lymphomas and autoimmune precursor lesions, suggesting possible involvement of C psittaci-induced antigenic-driven MALT lymphomagenesis.

Primary Cutaneous Marginal Zone B-Cell Lymphomas Are Targeted by Aberrant Somatic Hypermutation

A mechanism inducing genetic instability, termed aberrant somatic hypermutation (ASHM), has been described in diffuse large B-cell lymphoma. To further investigate whether ASHM also occurs in primary cutaneous marginal zone B-cell lymphoma (PCMZL), we studied the mutational profile of PAX5, RhoH/TTF, cMYC, and PIM1 in 11 PCMZLs. A total of 17 sequence variants were found in 8 of 11 lymphomas cases (72.7%), and they displayed the molecular features typical for the ASHM. Further, two mutations, one mutation in PIM1 and one in cMYC, led to amino-acid substitution with potential functional consequences. These data indicate that ASHM is associated with PCMZLs. By mutating regulatory and coding sequences of the targeted genes, ASHM may represent a major contributor to their pathogenesis.

Quantifying the role of aberrant somatic hypermutation in transformation of follicular lymphoma

Somatic hypermutation (SHM) aberrantly targets proto-oncogenes in various non-Hodgkins lymphoma. To test the association of SHM with transformation of follicular lymphoma (FL), we sequenced mutational hot spots in five proto-oncogenes (BCL6, PAX5, RHOH, MYC and PIM1) in 32 low-grade FL (lgFL) with follicular histology and 26 transformed FL (tFL) with diffuse large cell histology. No difference was detected in the fraction of specimens mutated (75% of lgFL and 77% of tFL) or in the mutation load (0.08 for lgFL vs. 0.06 mutations/100 bp/allele for tFL). Serial specimens were examined from 25 patients showing stable low-grade FL (slgFL; n=6) or a low-grade FL that later transformed into diffuse large cell lymphoma (tFL; n=19). slgFL and tFL patients accumulated similar numbers of mutations in the interval between biopsies. These data indicate that mutations attributable to aberrant SHM occur with similar frequency in low-grade and transformed FL; transformation is not associated with a higher rate of aberrant SHM. Moreover, the frequency of mutations attributable to aberrant SHM in tFL was significantly lower than that reported for de novo diffuse large B cell lymphoma, suggesting differing oncogenic mechanisms in transformed follicular lymphoma and de novo diffuse large B cell lymphoma.

Repeated fecal microbiota transplantations attenuate diarrhea and lead to sustained changes in the fecal microbiota in acute, refractory gastrointestinal graft-versus-host-disease

Acute graft- versus -host disease (aGvHD) is a serious complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT).[1][1] Although aGvHD of any target organ represents morbidity, lower gastrointestinal (GI) tract involvement is complicated by high mortality.[2][2] Here,

NEMO expression in human hepatocellular carcinoma and its association with clinical outcome

The nuclear factor κ-light-chain enhancer of activated B-cells (NF-κB) signaling pathway is regarded as an important factor in inflammation and carcinogenesis. Recently, a role in hepatocarcinogenesis has been attributed to the NF-κB regulatory subunit IKKγ (NEMO) using knockout mice. However, a detailed investigation of NEMO expression in human hepatocellular carcinomas (HCCs) has not yet been reported. We selected 85 HCC patients who had undergone curative liver resection and analyzed NEMO expression of the respective tumors by immunohistochemistry, Western blotting, and real-time PCR. NEMO expression was correlated with clinicopathological parameters, and the impact on 5-year disease-free survival and 5-year overall survival was calculated using multivariate Cox proportional models. In our study, complete loss of NEMO immunoreactivity was found in 34 (40%) of 85 HCCs compared with their adjacent nonneoplastic tissue (P < .05). NEMO messenger RNA (mRNA) expression was detected in all HCC cases; however, no correlation between NEMO immunoreactivity and mRNA level was found. Five-year overall survival rates for patients with low and high NEMO expression were 22% and 50%, respectively (P = .049). However, high tumor stage, but not level of NEMO expression, was confirmed as an independent poor prognostic factor for 5-year disease-free survival (hazards ratio [HR] = 2.1, 95% confidence interval [CI] = 1.3-3.6, P = .009) and 5-year overall survival (HR = 2.5, CI = 1.4-4.4, P = .002). In conclusion, a loss of NEMO immunoreactivity occurs in a substantial proportion of human HCCs. Although low NEMO expression is correlated with a poor 5-year overall survival in patients with HCC, NEMO cannot be regarded as an independent prognostic marker for predicting the clinical outcome of patients suffering from HCC.

NKG2D stimulated T-cell autoreactivity in giant cell arteritis and polymyalgia rheumatica

Objective To investigate functional expression of NKG2D on CD4 and CD8 T-cells in patients with giant cell arteritis (GCA) and polymyalgia rheumatica (PMR). Methods Peripheral blood was drawn from patients with GCA (n=16), PMR (n=78) and healthy controls (HC, n=64). Tissue samples were obtained from GCA patients and controls. Proliferation and cytokine production assays were performed using CFSE and intracellular IFN-γ or TNF-α staining, respectively, and flow cytometry analysis. Immunofluorescence and immunohistology were applied to analyse the presence of NKG2D-expressing T-cells and NKG2D-ligands in temporal arteries, respectively. mRNA levels of NKG2D-ligands were determined by RT-PCR. Results In both GCA and PMR patients, NKG2D was preferentially expressed on senescent CD4CD28− and CD8CD28−, as well as on CD8CD28 T-cells. Frequencies of senescent T-cells were increased in GCA and PMR patients compared to HC. In GCA tissue samples, infiltrating T-cells were predominately CD28−. NKG2D expressing T-cells concentrated around the vasa vasorum of the adventitia. Antigenic stimulation induced rapid up-regulation of NKG2D on CD4CD28− and CD4CD28 T-cells, whereas TNF-α and interleukin-15 enhanced NKG2D expression on senescent CD4 and CD8 T-cells only. NKG2D cross-linkage augmented anti-CD3 triggered proliferation, IFN-γ and TNF-α production of CD8 T-cells. In CD4CD28− T-cells, NKG2D ligation resulted in increased IFN-γ production only. NKG2D ligands were expressed in temporal arteries from GCA patients, particularly in the adventitial and medial layers of affected vessels. Conclusions NKG2D is functionally expressed on CD4CD28− and CD8 T-cells in GCA and PMR. NKG2D-ligands are present in temporal arteries and may co-stimulate NKG2D expressing T-cells.

Histiocytic Sarcoma – Targeted Therapy: Novel Therapeutic Options? A Series of 4 Cases

Background: Histiocytic sarcoma (HS) is a rare but highly aggressive disease. The cancer-specific survival of patients with HS is short and only limited response to conventional chemotherapy or radiation therapy is seen. Some data from single case reports have suggested efficacy for high-dose chemotherapy and autologous/allogeneic stem cell transplantation. Case Report: We report on 4 cases of HS, and demonstrate that different druggable receptors are expressed on HS. Using immunohistochemistry, we detected the expression of platelet-derived growth factor receptor, vascular endothelial growth factor receptor and epidermal growth factor receptor, which are all well-known targets for novel targeted agents. Based on the marker profile, different novel targeted therapies including imatinib, sorafenib and bevacizumab were applied to the patients. We observed a varying clinical course for each patient. Conclusion: In our case series, we demonstrated that different receptors, which represent potential targets for novel drugs, are expressed on HS tumor cells. For a definitive assessment of the efficacy of these agents a prospective case study of a larger number of patients should be performed.

How a Cell Deals with Abnormal Proteins

Defective protein folding is responsible for many diseases. Although these diseases seem to be quite diverse at the first glance, there is evidence for common pathogenetic principles. The basis of the pathological changes is the cell’s inability to prevent protein misfolding, to revert misfolded proteins to normal or to eliminate misfolded proteins by degradation. This could result in deposition of potentially cytotoxic protein aggregates (protein aggregation diseases). Chronic degenerative diseases of the central nervous system (e.g. Alzheimer’s and Parkinson’s disease), the amyloidoses, but also chronic liver diseases, for example alcoholic and nonalcoholic steatohepatitis, belong to this category of disorders. This review highlights general pathogenic principles of protein aggregation diseases based on immunohistochemical and biochemical studies as well as observations in a mouse model for protein aggregation in the context of alcoholic and nonalcoholic steatohepatitis. The cellular defense mechanisms involved in protein quality control as well as the pathogenesis of protein aggregation diseases will be discussed.