FDG-PET/CT is a powerful tool to predict and evaluate response to chimeric antigen receptor (CAR) T-cell therapy in Non-Hodgkin-Lymphoma (NHL).

Chimeric antigen receptor (CAR) T-cell therapy has dramatically shifted the landscape of treatment especially for Non-Hodgkin-Lymphoma (NHL). This study evaluates the role of fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) in NHL treated with CAR T-cell therapy concerning response assessment and prognosis.We evaluated 34 patients with NHL who received a CAR T-cell therapy between August 2019 and July 2022. All patients underwent a pre-therapeutic FDG-PET/CT (PET-0) 6 days prior and a post-therapeutic FDG-PET/CT (PET-1) 34 days after CAR T-cell therapy. Deauville score (DS) was used for evaluation of response to therapy and compared to a minimum follow-up of 5 months.19/34 (55.9%) patients achieved DS ≤ 3 on PET-1, the remaining 15 (44.1%) patients had DS > 3 on PET-1. 14/19 patients with DS ≤ 3 on PET-1 had no relapsed or refractory (r/r)-disease and were still alive at last follow-up. The other 5 patients had r/r-disease and 4 of these died. Except for two patients who had no r/r-disease, all other patients (13/15) with DS > 3 on PET-1 had r/r-disease and 12 of these subsequently died. Patients with DS ≤ 3 on PET-1 had significantly better progression free survival (PFS; HR: 5.7; p < 0.01) and overall survival (OS; HR: 5.0; p < 0.01) compared to patients with DS > 3 on PET-1. In addition, we demonstrated that patients with DS ≤ 4 on PET-0 tended to have longer PFS (HR: 3.6; p = 0.05).Early FDG-PET/CT using the established DS after CAR T-cell therapy is a powerful tool to evaluate response to therapy.

Continuous therapy response references for BCR::ABL1 monitoring in pediatric chronic myeloid leukemia.

Response to tyrosine kinase inhibitor (TKI) therapy in patients with chronic myeloid leukemia (CML) is monitored by quantification of BCR::ABL1 transcript levels. Milestones for assessing optimal treatment response have been defined in adult CML patients and are applied to children and adolescents although it is questionable whether transferability to pediatric patients is appropriate regarding genetic and clinical differences. Therefore, we analyzed the molecular response kinetics to TKI therapy in 129 pediatric CML patients and investigated whether response assessment based on continuous references can support an early individual therapy adjustment. We applied a moving quantiles approach to establish a high-resolution response target curve and contrasted the median responses in all patients with the median of the ideal target curve obtained from a subgroup of optimal responders. The high-resolution response target curve of the optimal responder group presents a valuable tool for continuous therapy monitoring of individual pediatric CML patients in addition to the fixed milestones. By further comparing BCR::ABL1 transcript levels with BCR::ABL1 fusion gene copy numbers, it is also possible to model the differential dynamics of BCR::ABL1 expression and cell number under therapy. The developed methodology can be transferred to other biomarkers for continuous therapy monitoring.

Various effects of AAV9-mediated ßARKct gene therapy on the heart in dystrophin-deficient (mdx) mice and δ-sarcoglycan-deficient (Sgcd-/-) mice.

So far effective strategies to treat cardiomyopathy in patients with muscular dystrophies are still not clearly defined. Previously, treatment with ß-blockers showed beneficial effects on the development of cardiomyopathy in dystrophin-deficient (mdx) mice, but not in δ-sarcoglycan-deficient (Sgcd-/-) mice. We therefore aimed to study a more specific approach to target maladaptive ß-adrenergic signalling in these mice. It has been shown that lowering cardiac G-protein-coupled-receptor-kinase-2 (GRK2) activity with ßARKct expression, a peptide inhibitor of protein-coupled-receptor-kinase-2 (GRK2), results in improvement of heart failure in several different animal models. We therefore investigated whether adeno-associated virus type 9 (AAV9)-mediated gene delivery of ßARKct, could ameliorate cardiac pathology in mdx and Sgcd-/- mice. We found that long-term treatment with AAV9- ßARKct-cDNA with a cardiac-specific promoter significantly improves left ventricular systolic function and reduces myocardial hypertrophy in mdx mice, whereas only mild beneficial effects on cardiac function is observed in Sgcd-/- mice. Interestingly, in contrast to mdx mice neither GRK2 nor nuclear-factor-kappaB (NFκB) were upregulated in Sgcd-/- mice. Taken together, effectiveness of AAV-mediated ßARKct therapy may vary between different genetic mutations and presumably depend on the state of adrenergic dysregulation mediated through the upregulation of GRK2.

Critical role of RAGE and HMGB1 in inflammatory heart disease.

Autoimmune response to cardiac troponin I (TnI) induces inflammation and fibrosis in the myocardium. High-mobility group box 1 (HMGB1) is a multifunctional protein that exerts proinflammatory activity by mainly binding to receptor for advanced glycation end products (RAGE). The involvement of the HMGB1-RAGE axis in the pathogenesis of inflammatory cardiomyopathy is yet not fully understood. Using the well-established model of TnI-induced experimental autoimmune myocarditis (EAM), we demonstrated that both local and systemic HMGB1 protein expression was elevated in wild-type (wt) mice after TnI immunization. Additionally, pharmacological inhibition of HMGB1 using glycyrrhizin or anti-HMGB1 antibody reduced inflammation in hearts of TnI-immunized wt mice. Furthermore, RAGE knockout (RAGE-ko) mice immunized with TnI showed no structural or physiological signs of cardiac impairment. Moreover, cardiac overexpression of HMGB1 using adeno-associated virus (AAV) vectors induced inflammation in the hearts of both wt and RAGE-ko mice. Finally, patients with myocarditis displayed increased local and systemic HMGB1 and soluble RAGE (sRAGE) expression. Together, our study highlights that HMGB1 and its main receptor, RAGE, appear to be crucial factors in the pathogenesis of TnI-induced EAM, because inhibition of HMGB1 and ablation of RAGE suppressed inflammation in the heart. Moreover, the proinflammatory effect of HMGB1 is not necessarily dependent on RAGE only. Other receptors of HMGB1 such as Toll-like receptors (TLRs) may also be involved in disease pathogenesis. These findings could be confirmed by the clinical relevance of HMGB1 and sRAGE. Therefore, blockage of one of these molecules might represent a novel therapeutic strategy in the treatment of autoimmune myocarditis and inflammatory cardiomyopathy.

Functional fingerprinting of human mesenchymal stem cells using high-throughput RNAi screening.

Mesenchymal stem cells (MSCs) are promising candidates for cellular therapies ranging from tissue repair in regenerative medicine to immunomodulation in graft versus host disease after allogeneic transplantation or in autoimmune diseases. Nonetheless, progress has been hampered by their enormous phenotypic as well as functional heterogeneity and the lack of uniform standards and guidelines for quality control. In this study, we describe a method to perform cellular phenotyping by high-throughput RNA interference in primary human bone marrow MSCs. We have shown that despite heterogeneity of MSC populations, robust functional assays can be established that are suitable for high-throughput and high-content screening. We profiled primary human MSCs against human fibroblasts. Network analysis showed a kinome fingerprint that differs from human primary fibroblasts as well as fibroblast cell lines. In conclusion, this study shows that high-throughput screening in primary human MSCs can be reliably used for kinome fingerprinting.

Systematic approaches to dissect biological processes in stem cells by image-based screening.

High-throughput RNAi or small molecule screens have proven to be powerful methodologies for the systematic dissection of cellular processes. In model organisms and cell lines, large-scale screens have identified key components of many cellular pathways and helped to identify novel targets in disease-relevant pathways. Image-based high-content screening has become an increasingly important tool in high-throughput screening, enabling changes in phenotype characteristics, such as cell morphology and cell differentiation, to be monitored. In this review, we discuss the use of image-based screening approaches to explore the behavior of adult, embryonic, and induced pluripotent stem cells. First, we review how current pluripotency and differentiation assays can be adapted to high-throughput formats. We then describe general aspects of image-based screening of cells and present an outlook on challenges for screening stem cells.

Beta2-integrin activation on T cell subsets is an independent prognostic factor in unstable angina pectoris.

BACKGROUND: Cardiac troponins provide excellent risk stratification in unstable angina (UA), but no reliable markers are available in troponin-negative patients. Beta2-integrin mediated T cell recruitment plays a pivotal role in coronary atherosclerotic plaque rupture. The present study investigates beta2-integrin activation on T cell subsets as a risk marker in UA. METHODS: Functional activation (affinity/avidity) of beta2-integrins on T cells was measured using a flow cytometry-based whole blood assay in 87 patients with UA. RESULTS: Beta2-integrin activation was significantly higher in patients with severe coronary artery disease (sC) and myocardial infarction (MI) compared to patients with no/minimal coronary atherosclerosis (no/mC), irrespective of troponin status. Adjusted for cardiovascular risk factors, medication, left ventricular function, MI at enrollment and high sensitivity C-reactive protein (hsCRP), beta2-integrin activation was independently associated with incidence of revascularization, hospitalization and all major cardiovascular events during 9 months of follow-up after index investigation. The highest prognostic value of beta2-integrin activation was seen in troponin-and hsCRP-negative patients. CONCLUSION: Quantitative assessment of T cell beta2-integrin activation allows to identify high risk patients with UA and sC without established MI; furthermore, it is associated with incidence of future cardiovascular events independent of conventional risk factors (troponin, hsCRP).

Cardiac troponin I but not cardiac troponin T induces severe autoimmune inflammation in the myocardium.

BACKGROUND: Cardiac troponins in blood are the most preferred markers of myocardial damage. The fact that they are normally not found in the circulation provides a high level of clinical sensitivity and specificity even when cardiac lesions are small. After myocardial injury, the troponins enter the circulation, where they can be used for diagnosis of acute coronary syndromes. Thus, the cardiac troponins are paramount for disease classification and risk stratification. However, little is known about the long-term effects of the released troponins on cardiac function. METHODS AND RESULTS: In this study we prepared recombinant murine cardiac troponin I (mc-TnI) and murine cardiac troponin T and used them to immunize mice. We report that A/J mice immunized with mc-TnI developed severe inflammation of the myocardium with increased expression of inflammatory chemokines RANTES (regulated on activation normal T cell expressed and secreted), monocyte chemoattractant protein-1, macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, MIP-2, T-cell activation gene 3, and eotaxin and chemokine receptors CCR1, CCR2, and CCR5. The inflammation was followed by cardiomegaly, fibrosis, reduced fractional shortening, and 30% mortality over 270 days. In contrast, mice immunized with murine cardiac troponin T or with the control buffer showed little or no inflammation and no death. Furthermore, we demonstrate that mice preimmunized with mc-TnI before left anterior descending coronary artery ligation showed greater infarct size, more fibrosis, higher inflammation score, and reduced fractional shortening. CONCLUSIONS: Overall, our results show for the first time that provocation of an autoimmune response to mc-TnI induces severe inflammation in the myocardium followed by fibrosis and heart failure with increased mortality in mice.

Posttranslationally modified proteins as mediators of sustained intestinal inflammation.

Oxidative and carbonyl stress leads to generation of N(epsilon)-carboxymethyllysine-modified proteins (CML-mps), which are known to bind the receptor for advanced glycation end products (RAGE) and induce nuclear factor (NF)-kappaB-dependent proinflammatory gene expression. To determine the impact of CML-mps in vivo, RAGE-dependent sustained NF-kappaB activation was studied in resection gut specimens from patients with inflammatory bowel disease. Inflamed gut biopsy tissue demonstrated a significant up-regulation of RAGE and increased NF-kappaB activation. Protein extracts from the inflamed zones, but not from noninflamed resection borders, caused perpetuated NF-kappaB activation in cultured endothelial cells, which was mediated by CML-mps including CML-modified S100 proteins. The resulting NF-kappaB activation, lasting 5 days, was primarily inhibited by either depletion of CML-mps or by the addition of sRAGE, p44/42 and p38 MAPKinase-specific inhibitors. Consistently, CML-mps isolated from inflamed gut areas and rectally applied into mice caused NF-kappaB activation, increased proinflammatory gene expression, and histologically detectable inflammation in wild-type mice, but not in RAGE-/- mice. A comparable up-regulation of NF-kappaB and inflammation on rectal application of CML-mps was observed in IL-10-/- mice. Thus, CML-mps generated in inflammatory lesions have the capacity to elicit a RAGE-dependent intestinal inflammatory response.