Rasmus Røge

Immunomodulatory effects of clozapine and their clinical implications: what have we learned so far?

Clozapine remains the drug of choice for treatment resistant schizophrenia, but is associated with potentially life threatening side effects, including agranulocytosis and myocarditis. Immunological mechanisms may be involved in the development of these side effects or in the unique antipsychotic efficacy in subgroups of schizophrenia patients. This systematic review presents the immunomodulatory effects of clozapine from human in vitro and in vivo studies and relates these findings to the developments of adverse and therapeutic effects of clozapine. Several studies confirm the immunomodulatory actions of clozapine, but only few studies investigated their relationship to the unique adverse and therapeutic effects of clozapine. During the first month of clozapine treatment, up to 50% of patients develop fever and flu like symptoms, which is seemingly driven by increased cytokines. Within the same time period, the risk of side-effects with a suspected immunological mechanism peaks. Patients developing fever during the first weeks of treatment should have a thorough physical examination, and measurements of white blood cell count, absolute neutrophil count, ECG, C-reactive protein, creatinine kinase, and troponin to exclude infection, agranulocytosis, myocarditis and neuroleptic malignant syndrome. To what degree the unique antipsychotic efficacy of clozapine in subgroups of schizophrenia patients is related to its immunomodulatory effects has not been studied. Research relating the immunomodulatory actions of clozapine and its early markers to clinically relevant adverse and therapeutic outcomes is hoped to provide new leads for the understanding of the pathophysiology of schizophrenia and aid the development of novel treatment targets.

Soluble Urokinase-Type Plasminogen Activator Receptor Levels in Patients With Schizophrenia

BACKGROUND The etiology of schizophrenia remains largely unknown but alterations in the immune system may be involved. In addition to the psychiatric symptoms, schizophrenia is also associated with up to 20 years reduction in life span. Soluble urokinase-type plasminogen activator receptor (suPAR) is a protein that can be measured in blood samples and reflects the levels of inflammatory activity. It has been associated with mortality and the development of type 2 diabetes and cardiovascular disease. METHODS suPAR levels in patients with schizophrenia were compared to healthy controls from the Danish Blood Donor Study. SuPAR levels were dichotomized at >4.0 ng/ml, which is considered the threshold for low grade inflammation. A multiple logistic regression model was used and adjusted for age, sex, and current smoking. RESULTS In total we included 1009 subjects, 105 cases with schizophrenia (10.4%) and 904 controls (89.6%). The mean suPAR values were 4.01 ng/ml (SD = 1.43) for the cases vs 1.91 ng/ml (SD = 1.35) for the controls (P < .001). Multiple logistic regression with odds ratio (OR) for suPAR levels >4.0 ng/ml yielded: schizophrenia, OR: 46.15 95% CI 22.69-93.87, P < .001; age, OR: 1.02 95% CI 0.99-1.02, P = .15; male sex, OR: 0.70 95% CI 0.35-1.36, P = .29; and current smoking, OR: 3.51 95% CI 1.78-6.94, P < .001. CONCLUSIONS Patients with schizophrenia had significantly higher suPAR levels than healthy controls. Further studies are warranted to clarify if elevated suPAR levels are involved in the pathophysiology of schizophrenia and/or the increased mortality found in patients with schizophrenia.

Accurate PD-L1 Protocols for Non-Small Cell Lung Cancer can be Developed for Automated Staining Platforms With Clone 22C3

Treatment using immunotherapy against PD-L1 or PD-1 has become one of the hottest topics in Pathology and Oncology. Correct selection of patients eligible for treatment requires optimal immunohistochemical staining protocols. Treatment with pembrolizumab requires diagnostic examination of the patients tumour using the companion diagnostic Ready-To-Use pharmDx kit from Dako Agilent based on the mAb 22C3 clone on the Autostainer platform. However, not all diagnostic pathology labs have access to this staining platform. This purpose of this study was to develop and validate protocols for PD-L1 detection for all major staining platforms using the concentrated format of 22C3 that would give similar staining result (equal Tumour Proportion Scores) to the pharmDx kit.

An association between autumn birth and clozapine treatment in patients with schizophrenia: a population-based analysis.

Abstract Background: Numerous studies on seasonality of birth and schizophrenia risk have been published but it is uncertain whether, among those with schizophrenia, refractory illness exhibits any predilection for birth month. We hypothesized and examined whether a season of birth effect was present in patients with schizophrenia with a history of clozapine treatment. Method: Using record linkage with Danish registers, we examined patients with schizophrenia born between 1950 and 1970, and between 1995 and 2009 and Cox regression analysis was used to examine season of birth in relation to history of clozapine treatment. Results: In a study population corresponding to 60,062 person-years from 5328 individuals with schizophrenia of which 1223 (23%) received at least one clozapine prescription, birth in the autumn (September–November) was associated with clozapine treatment (HR = 1.24; 95% CI 1.07–1.46) when compared with birth in the spring (March–May). Conclusion: Although replication studies are needed, this is the first evidence from a nationwide study suggesting a possible season-associated risk of clozapine treatment in schizophrenia. The reasons for this relationship remain to be further investigated but might be partially explained by early exposures such as winter flu season and low vitamin D levels.

Antibody-Directed Glucocorticoid Targeting to CD163 in M2-type Macrophages Attenuates Fructose-Induced Liver Inflammatory Changes

Increased consumption of high-caloric carbohydrates contributes substantially to endemic non-alcoholic fatty liver disease in humans, covering a histological spectrum from fatty liver to steatohepatitis. Hypercaloric intake and lipogenetic effects of fructose and endotoxin-driven activation of liver macrophages are suggested to be essential to disease progression. In the present study, we show that a low dose of an anti-CD163-IgG-dexamethasone conjugate targeting the hemoglobin scavenger receptor CD163 in Kupffer cells and other M2-type macrophages has a profound effect on liver inflammatory changes in rats on a high-fructose diet. The diet induced severe non-alcoholic steatohepatitis (NASH)-like changes within a few weeks but the antibody-drug conjugate strongly reduced inflammation, hepatocyte ballooning, fibrosis, and glycogen deposition. Non-conjugated dexamethasone or dexamethasone conjugated to a control IgG did not have this effect but instead exacerbated liver lipid accumulation. The low-dose anti-CD163-IgG-dexamethasone conjugate displayed no apparent systemic side effects. In conclusion, macrophage targeting by antibody-directed anti-inflammatory low-dose glucocorticoid therapy seems to be a promising approach for safe treatment of fructose-induced liver inflammation.

Using cell nuclei features to detect colon cancer tissue in hematoxylin and eosin stained slides

Currently, diagnosis of colon cancer is based on manual examination of histopathological images by a pathologist. This can be time consuming and interpretation of the images is subject to inter‐ and intra‐observer variability. This may be improved by introducing a computer‐aided diagnosis (CAD) system for automatic detection of cancer tissue within whole slide hematoxylin and eosin (H&E) stains. Cancer disrupts the normal control mechanisms of cell proliferation and differentiation, affecting the structure and appearance of the cells. Therefore, extracting features from segmented cell nuclei structures may provide useful information to detect cancer tissue. A framework for automatic classification of regions of interest (ROI) containing either benign or cancerous colon tissue extracted from whole slide H&E stained images using cell nuclei features was proposed. A total of 1,596 ROIs were extracted from 87 whole slide H&E stains (44 benign and 43 cancer). A cell nuclei segmentation algorithm consisting of color deconvolution, k‐means clustering, local adaptive thresholding, and cell separation was performed within the ROIs to extract cell nuclei features. From the segmented cell nuclei structures a total of 750 texture and intensity‐based features were extracted for classification of the ROIs. The nine most discriminative cell nuclei features were used in a random forest classifier to determine if the ROIs contained benign or cancer tissue. The ROI classification obtained an area under the curve (AUC) of 0.96, sensitivity of 0.88, specificity of 0.92, and accuracy of 0.91 using an optimized threshold. The developed framework showed promising results in using cell nuclei features to classify ROIs into containing benign or cancer tissue in H&E stained tissue samples.

Carb-3 Is the Superior Anti-CD15 Monoclonal Antibody for Immunohistochemistry

Immunohistochemical detection of CD15 is important in the diagnosis of Hodgkin lymphoma and may play a role in the classification of renal cell tumors (RCTs). In the NordiQC external quality assessment scheme, 4 CD15 tests, each with 71 to 121 participating laboratories, showed that 24% to 50% of the stains were insufficient. This was mainly because of very low primary antibody (Ab) concentration and insufficient heat-induced epitope retrieval, whereas the Ab clone performance seemed of little importance. The purpose of this study was to evaluate the performance of the most commonly used CD15 Abs on the basis of vendor-recommended and in-house optimized protocols. Multitissue blocks with 199 specimens including various malignant lymphomas, RCTs, and normal tissues were stained with 3 different concentrated (conc) CD15 Ab clones Carb-3, MMA, and BY87 according to predetermined in-house optimized protocols on 2 automated immunostaining platforms. Carb-3 and MMA were also applied in ready-to-use (RTU) formats utilized according to vendor protocols. Extension and intensity of stains was determined using the H-score method. Clone Carb-3-conc gave with an in-house optimized protocol the highest H-scores in Hodgkin lymphoma, RCTs, and normal kidney tissue. Clones Carb-3-RTU and MMA-conc gave slightly lower scores, whereas clones MMA-RTU and BY87-conc gave the lowest scores and a large proportion of false-negative reactions. For all concentrated Abs, in-house optimized protocols resulted in increased sensitivity and improved overall staining results compared with vendor-recommended protocols. The importance of Ab selection and protocol optimization in immunohistochemical laboratories is emphasized.

Exploiting Multiple Color Representations to Improve Colon Cancer Detection in Whole Slide H&E Stains

Currently, colon cancer diagnosis is based on manual assessment of tissue samples stained with hematoxylin and eosin (H&E). This is a high volume, time consuming, and subjective task which could be aided by automatic cancer detection. We propose an algorithm for automatic cancer detection within WSI H&E stains using a multi class colon tissue classifier based on features extracted from 5 different color representations. Approx. 32000 tissue patches were extracted for the classifier from manual annotations of 9 representative colon tissue types from 74 WSI H&E stains. Colon tissue classifiers based on gray level or color features were trained using leave-one-out forward selection. The best colon tissue classifier was based on color texture features obtaining an average tissue precision-recall (PR) area under the curve (AUC) of 0.886 and a cancer PR-AUC of 0.950 on 20 validation WSI H&E stains.

NordiQC Assessments of PAX8 Immunoassays

This paper is number 1 in a series developed through a partnership between ISIMM and NordiQC for the purpose of reporting research assessing the performance characteristics of immunoassays in an external proficiency testing program.

Quantitative tumor heterogeneity assessment on a nuclear population basis

Immunohistochemistry Ki‐67 stain is widely used for visualizing cell proliferation. The common method for scoring the proliferation is to manually select and score a hot spot. This method is time‐consuming and will often not give reproducible results due to subjective selection of the hotspots and subjective scoring. An automatic hotspot detection and proliferative index scoring would be time‐saving, make the determination of the Ki‐67 score easier and minimize the uncertainty of the score by introducing a more objective and standardized score.