Intelligent image-based deformation-assisted cell sorting with molecular specificity.

Although label-free cell sorting is desirable for providing pristine cells for further analysis or use, current approaches lack molecular specificity and speed. Here, we combine real-time fluorescence and deformability cytometry with sorting based on standing surface acoustic waves and transfer molecular specificity to image-based sorting using an efficient deep neural network. In addition to general performance, we demonstrate the utility of this method by sorting neutrophils from whole blood without labels.

Real-time fluorescence and deformability cytometry.

The throughput of cell mechanical characterization has recently approached that of conventional flow cytometers. However, this very sensitive, label-free approach still lacks the specificity of molecular markers. Here we developed an approach that combines real-time 1D-imaging fluorescence and deformability cytometry in one instrument (RT-FDC), thus opening many new research avenues. We demonstrated its utility by using subcellular fluorescence localization to identify mitotic cells and test for mechanical changes in those cells in an RNA interference screen.

Only partial improvement in health-related quality of life after treatment of chronic hepatitis C virus infection with direct acting antivirals in a real-world setting-results from the German Hepatitis C-Registry (DHC-R).

Improvement of health-related quality of life (HRQoL) is frequently reported as a benefit when treating hepatitis C virus infection (HCV) with direct acting antivirals (DAA). As most of the available data were obtained from clinical trials, limited generalizability to the real-world population might exist. This study aimed to investigate the impact of DAA therapy on changes in HRQoL in a real-world setting. HRQoL of 1180 participants of the German Hepatitis C-Registry was assessed by Short-Form 36 (SF-36) questionnaires. Scores at post-treatment weeks 12-24 (FU12/24) were compared to baseline (BL). Changes of ≥2.5 in mental and physical component summary scores (MCS and PCS) were defined as a minimal clinical important difference (MCID). Potential predictors of HRQoL changes were analysed. Overall, a statistically significant increase in HRQoL after DAA therapy was observed, that was robust among various subgroups. However, roughly half of all patients failed to achieve a clinically important improvement in MCS and PCS. Low MCS (p < .001, OR = 0.925) and PCS (p < .001, OR = 0.899) BL levels were identified as predictors for achieving a clinically important improvement. In contrast, presence of fatigue (p = .023, OR = 1.518), increased GPT levels (p = .005, OR = 0.626) and RBV containing therapy regimens (p = .001, OR = 1.692) were associated with a clinically important decline in HRQoL after DAA therapy. In conclusion, DAA treatment is associated with an overall increase of HRQoL in HCV-infected patients. Nevertheless, roughly half of the patients fail to achieve a clinically important improvement. Especially patients with a low HRQoL seem to benefit most from the modern therapeutic options.

Real-time deformability cytometry: on-the-fly cell mechanical phenotyping.

We introduce real-time deformability cytometry (RT-DC) for continuous cell mechanical characterization of large populations (>100,000 cells) with analysis rates greater than 100 cells/s. RT-DC is sensitive to cytoskeletal alterations and can distinguish cell-cycle phases, track stem cell differentiation into distinct lineages and identify cell populations in whole blood by their mechanical fingerprints. This technique adds a new marker-free dimension to flow cytometry with diverse applications in biology, biotechnology and medicine.

Conformations and membrane-driven self-organization of rodlike fd virus particles on freestanding lipid membranes.

Membrane-mediated interactions and aggregation of colloidal particles adsorbed to responsive elastic membranes are challenging problems relevant for understanding the microscopic organization and dynamics of biological membranes. We experimentally study the behavior of rodlike semiflexible fd virus particles electrostatically adsorbed to freestanding cationic lipid membranes and find that their behavior can be controlled by tuning the membrane charge and ionic strength of the surrounding medium. Three distinct interaction regimes of rodlike virus particles with responsive elastic membranes can be observed. (i) A weakly charged freestanding cationic lipid bilayer in a low ionic strength medium represents a gentle quasi-2D substrate preserving the integrity, structure, and mechanical properties of the membrane-bound semiflexible fd virus, which under these conditions is characterized by a monomer length of 884 ± 4 nm and a persistence length of 2.5 ± 0.2 µm, in perfect agreement with its properties in bulk media. (ii) An increase in the membrane charge leads to the membrane-driven collapse of fd virus particles on freestanding lipid bilayers and lipid nanotubes into compact globules. (iii) When the membrane charge is low, and the mutual electrostatic repulsion of membrane-bound virus particles is screened to a considerable degree, membrane-driven self-organization of membrane-bound fd virus particles into long linear tip-to-tip aggregates showing dynamic self-assembly/disassembly and quasi-semiflexible behavior takes place. These observations are in perfect agreement with the results of recent theoretical and simulation studies predicting that membrane-mediated interactions can control the behavior of colloidal particles adsorbed on responsive elastic membranes.

Biomarkers of Hepatic Fibrosis in Chronic Hepatitis C: A Comparison of 10 Biomarkers Using 2 Different Assays for Hyaluronic Acid.

BACKGROUND: Advancing fibrosis is regarded as the most important factor when stratifying patients with chronic hepatitis C for retreatment. GOALS: (1) To compare the performance of 10 biomarkers of fibrosis, including patented tests, among patients with chronic hepatitis C and treatment failure; and (2) to assess the impact on biomarker performance of using 2 different assays of hyaluronic acid (HA). STUDY: For 80 patients, liver histology (Metavir) was compared with biomarker scores using sera obtained within 6 months of liver biopsy (indirect biomarkers: AST:ALT ratio, APRI, Forns index, FIB-4, Fibrometer V3G; direct biomarkers: ELF, Fibrospect II, Hyaluronic acid-HA, Fibrometer V2G, Hepascore). Direct biomarker scores were calculated using 2 validated assays for HA (ELISA and radiometric). RESULTS: Using the ELISA assay for HA to calculate the direct panels, all 10 of the biomarkers exhibited comparable overall discriminatory performance (unweighted Obuchowski measure, ordROC 0.92-0.94, P-value>0.05) except AST:ALT ratio and APRI (ordROC 0.86-0.88, P-value<0.05). For the detection of moderate (F2-4) and advanced (F3-4) fibrosis, the AUROC of Fibrometer 2G were significantly higher than AST:ALT ratio and APRI but none of the other biomarkers. Good correlation was observed between the 2 HA assays (intraclass correlation coefficient=0.873) with the ELISA assay exhibiting superior diagnostic performance (ordROC 0.92 vs. 0.88, P-value=0.003). Importantly, the performance of many of the direct biomarkers at their diagnostic thresholds was heavily influenced by the choice of HA assay. CONCLUSIONS: Although many biomarkers exhibited good diagnostic performance for the detection of advancing fibrosis, our results indicate that diagnostic performance may be significantly affected by the selection of individual component assays.

Long-range transport of giant vesicles along microtubule networks.

We report on a minimal system to mimic intracellular transport of membrane-bounded, vesicular cargo. In a cell-free assay, purified kinesin-1 motor proteins were directly anchored to the membrane of giant unilamellar vesicles, and their movement studied along two-dimensional microtubule networks. Motion-tracking of vesicles with diameters of 1-3 µm revealed traveling distances up to the millimeter range. The transport velocities were identical to velocities of cargo-free motors. Using total internal reflection fluorescence (TIRF) microscopy, we were able to estimate the number of GFP-labeled motors involved in the transport of a single vesicle. We found that the vesicles were transported by the cooperative activity of typically 5-10 motor molecules. The presented assay is expected to open up further applications in the field of synthetic biology, aiming at the in vitro reconstitution of sub-cellular multi-motor transport systems. It may also find applications in bionanotechnology, where the controlled long-range transport of artificial cargo is a promising means to advance current lab-on-a-chip systems.

Efficient electroformation of supergiant unilamellar vesicles containing cationic lipids on ITO-coated electrodes.

Giant unilamellar vesicles (GUVs) represent a versatile in vitro system widely used to study properties of lipid membranes and their interaction with biomacromolecules and colloids. Electroformation with indium tin oxide (ITO) coated coverslips as electrodes is a standard approach to GUV production. In the case of cationic GUVs, however, application of this approach leads to notorious difficulties. We discover that this is related to aging of ITO-coated coverslips during their repeated use, which is reflected in their surface topography on the nanoscale. We find that mild annealing of the ITO-coated surface in air reverts the effects of aging and ensures efficient reproducible electroformation of supergiant (diameter > 100 µm) unilamellar vesicles containing cationic lipids.

Depressive disorders are associated with increased peripheral blood cell deformability: a cross-sectional case-control study (Mood-Morph).

Pathophysiological landmarks of depressive disorders are chronic low-grade inflammation and elevated glucocorticoid output. Both can potentially interfere with cytoskeleton organization, cell membrane bending and cell function, suggesting altered cell morpho-rheological properties like cell deformability and other cell mechanical features in depressive disorders. We performed a cross-sectional case-control study using the image-based morpho-rheological characterization of unmanipulated blood samples facilitating real-time deformability cytometry (RT-DC). Sixty-nine pre-screened individuals at high risk for depressive disorders and 70 matched healthy controls were included and clinically evaluated by Composite International Diagnostic Interview leading to lifetime and 12-month diagnoses. Facilitating deep learning on blood cell images, major blood cell types were classified and morpho-rheological parameters such as cell size and cell deformability of every individual cell was quantified. We found peripheral blood cells to be more deformable in patients with depressive disorders compared to controls, while cell size was not affected. Lifetime persistent depressive disorder was associated with increased cell deformability in monocytes and neutrophils, while in 12-month persistent depressive disorder erythrocytes deformed more. Lymphocytes were more deformable in 12-month major depressive disorder, while for lifetime major depressive disorder no differences could be identified. After correction for multiple testing, only associations for lifetime persistent depressive disorder remained significant. This is the first study analyzing morpho-rheological properties of entire blood cells and highlighting depressive disorders and in particular persistent depressive disorders to be associated with increased blood cell deformability. While all major blood cells tend to be more deformable, lymphocytes, monocytes, and neutrophils are mostly affected. This indicates that immune cell mechanical changes occur in depressive disorders, which might be predictive of persistent immune response.

Peginterferon alfa-2a relapse rates depend on weight-based ribavirin dosage in HCV-infected patients with genotype 1: results of a retrospective evaluation.

OBJECTIVE: The cumulative dosage of ribavirin per kilogram of body-weight prevents relapse and thus is a significant predictor of sustained virological response (SVR). Comparison of peginterferon (peg-IFN) alfa-2b/ribavirin and peg-IFN alfa-2a/ribavirin shows that the rates of SVR are similar, but the rates of relapse are significantly lower under the peg-IFN alfa-2b regimen. Depending on the weight-based ribavirin dose, patients with >105 kg reach a maximum of 13.2 mg/kg body-weight ribavirin in the peg-IFN alfa-2b regimen as opposed to only 11.3 mg/kg in the peg-IFN alfa-2a regimen. The aim of these investigations was to determine relapse rates in a retrospective analysis of 98 patients chronically infected with hepatitis C virus (HCV) genotype (GT) 1 in relation to the weight-based ribavirin dose. MATERIAL AND METHODS: All patients completed treatment with peg-IFN alfa-2a/ribavirin (1000 mg/d or 1200 mg/d for patients weighing <75 kg or > or =75 kg) for 48 weeks. Classification of a low ribavirin dose with <13.2 mg/kg body-weight was used. Patients with a ribavirin dose > or =13.2 mg/kg were compared with those with a dose <13.2 mg/kg. RESULTS: Patients with a ribavirin dose > or = 13.2 mg/kg (n=84) showed a relapse rate of 19.0% in contrast to 71.4% in patients with a ribavirin dose of <13.2 mg/kg (n=14) (p=0.0013). The SVR rate was significantly higher in the > or =13.2 mg/kg ribavirin dosed group (59.5% versus 28.6%). CONCLUSIONS: Weight-adapted ribavirin dosing in combination with peg-IFN alfa-2a to avoid giving low doses of ribavirin should be evaluated. This will minimize relapse, especially in HCV GT 1 patients.

Real-time deformability cytometry reveals sequential contraction and expansion during neutrophil priming.

It has become increasingly apparent that the biomechanical properties of neutrophils impact on their trafficking through the circulation and in particularly through the pulmonary capillary bed. The retention of polarized or shape-changed neutrophils in the lungs was recently proposed to contribute to acute respiratory distress syndrome pathogenesis. Accordingly, this study tested the hypothesis that neutrophil priming is coupled to morpho-rheological (MORE) changes capable of altering cell function. We employ real-time deformability cytometry (RT-DC), a recently developed, rapid, and sensitive way to assess the distribution of size, shape, and deformability of thousands of cells within seconds. During RT-DC analysis, neutrophils can be easily identified within anticoagulated "whole blood" due to their unique granularity and size, thus avoiding the need for further isolation techniques, which affect biomechanical cell properties. Hence, RT-DC is uniquely suited to describe the kinetics of MORE cell changes. We reveal that, following activation or priming, neutrophils undergo a short period of cell shrinking and stiffening, followed by a phase of cell expansion and softening. In some contexts, neutrophils ultimately recover their un-primed mechanical phenotype. The mechanism(s) underlying changes in human neutrophil size are shown to be Na+ /H+ antiport-dependent and are predicted to have profound implications for neutrophil movement through the vascular system in health and disease.

The dual EGF/VEGF receptor tyrosine kinase inhibitor AEE788 inhibits growth of human hepatocellular carcinoma xenografts in nude mice.

We investigated the effect of AEE788, a novel dual receptor tyrosine kinase inhibitor of the EGF and the VEGF receptor, for treatment of human HCC cell lines and in a subcutaneous xenograft model. Cell viability and apoptosis of HepG2 and Hep3B cells incubated with 0.1-100 microM AEE788 were quantified. In vivo, HepG2 cells were xenografted to NMRI mice and animals were treated orally with 50 mg/kg AEE788 3x/week. Immunohistochemistry and quantitative Western blotting was performed for pathway analysis in vitro and in vivo. AEE788 reduced growth and induced apoptosis of HCC cells by disrupting mitochondrial transmembrane potentials and inhibiting MAPK phosphorylation. In the xenografts, AEE788 lead to a reduced tumor growth by reducing proliferation and vascularisation. Except for a reversible skin reaction and weight loss, no signs of toxicity were observed. AEE788 is a promising new option for the treatment of HCC.

The histone-deacetylase inhibitor MS-275 and the CDK-inhibitor CYC-202 promote anti-tumor effects in hepatoma cell lines.

Effective therapies for advanced stages of hepatocellular carcinoma (HCC) have yet to be developed. We investigated how far a combination of the HDAC inhibitor MS-275 and the CDK inhibitor CYC-202 synergizes to inhibit proliferation and promotes apoptosis of hepatoma cells in vitro. Human hepatoma cell lines Hep3B and HepG2 as well as primary human foreskin fibroblasts as non-malignant controls were cultured under standardized conditions and incubated with increasing concentrations of CYC-202 and MS-275 as single agents and in combination. After 24 to 72 h, apoptosis was analyzed by flow cytometry (propidium iodide, JC-1) and by immunocytochemistry for cytokeratin 18 fragmentation. DNA synthesis was assessed using bromodeoxyuridine incorporation. Protein was separated for Western blotting against p21, bax and bcl-2 and fluorimetric activity assays against caspase 3 and 8. The results showed that the combination of CYC-202 and MS-275 leads to better pro-apoptotic effects than the employment of single substances. Apoptosis was induced via the mitochondrial pathway as evidenced by a shift in the bax/bcl-2 ratio and breakdown of mitochondrial transmembrane potentials. Caspase assays revealed a strong induction of caspase 3 but not of the extrinsic initiator caspase 8. In conclusion, combination therapy with the biomodulators MS-275 and CYC-202 is a promising treatment option for HCC.

Detection of human disease conditions by single-cell morpho-rheological phenotyping of blood.

Blood is arguably the most important bodily fluid and its analysis provides crucial health status information. A first routine measure to narrow down diagnosis in clinical practice is the differential blood count, determining the frequency of all major blood cells. What is lacking to advance initial blood diagnostics is an unbiased and quick functional assessment of blood that can narrow down the diagnosis and generate specific hypotheses. To address this need, we introduce the continuous, cell-by-cell morpho-rheological (MORE) analysis of diluted whole blood, without labeling, enrichment or separation, at rates of 1000 cells/sec. In a drop of blood we can identify all major blood cells and characterize their pathological changes in several disease conditions in vitro and in patient samples. This approach takes previous results of mechanical studies on specifically isolated blood cells to the level of application directly in blood and adds a functional dimension to conventional blood analysis.

The combination of the histone-deacetylase inhibitor trichostatin A and gemcitabine induces inhibition of proliferation and increased apoptosis in pancreatic carcinoma cells.

The prognosis of advanced pancreatic cancer is poor. Established chemotherapy shows only limited efficacy and significant side effects. We investigated how far a combination of trichostatin A (TSA) and gemcitabine synergizes to inhibit proliferation and promotion of apoptosis of pancreatic adenocarcinoma cells in vitro. The human pancreatic carcinoma cells YAPC, DANG and Panc-89 and primary human foreskin fibroblasts as non-malignant controls were cultured under standardized conditions and incubated with gemcitabine und TSA alone (10(-4) to 10(-8) M) or together (10(-6) to 10(-7) M). After 24-72 h the apoptotic rate was analyzed by flow cytometry (propidium iodide, FACS). DNA-synthesis was assessed using bromodeoxyuridine (BrdU) incorporation. Protein was separated for Western blotting against caspase-3 and -8, p21, bax and bcl-2. The combination of TSA und gemcitabine leads to better pro-apoptotic effects than the employment of single substances. Bcl-2, a mitochondrial protein, which protects against apoptosis, was not expressed. Bax, an apoptosis inducing protein, which destabilizes the mitochondrial membrane potential, was increasingly expressed. Combination of TSA and gemcitabine shows promise for treatment of pancreatic cancer in vivo.

Differential response of p53 and p21 on HDAC inhibitor-mediated apoptosis in HCT116 colon cancer cells in vitro and in vivo.

We investigated the effect of a novel histone deacetylase inhibitor, A-423378.0, on the colon carcinoma cell line HCT116 and genetically modified derivatives lacking either p21(cip1/waf1) or p53. HCT116 cell lines were incubated with A-423378.0 at different concentrations for 3-120 h. Cell viability, proliferation and apoptosis rates were determined and verified by western blot, detection of mitochondrial membrane potential breakdown DeltaPsi(m), activation of caspases-3, -8 and cytokeratin 18 cleavage. A subcutaneous xenograft model was established in NMRI mice with daily intraperitoneal injections of 10 mg/kg for 14 days. All three HCT116 cell lines responded to A-423378.0 treatment in a dose- and time-dependent manner via induction of apoptosis as measured by breakdown of DeltaPsi(m) and BrdU incorporation. We identified that A-423378.0 induced the expression of TRAIL and TRAIL receptor, especially TRAIL-R2/hDR5, which was up-regulated in HCT116 cells after treatment with A-423378.0. In vivo, a growth inhibitory effect was observed with HDAC-I treatment, which was paralleled by a down-regulation of PCNA and a concomitant induction of apoptosis. Treatment of wild-type or knock-out HCT116 cells with A-423378.0 exerts potent anti-proliferative and pro-apoptotic effects in vitro and in vivo. A-423378.0 was able to induce apoptosis in both p21(WAF1) and p53 deficient tumour cells, which appeared to be mediated by the intrinsic cell death pathway. Interestingly, the effects of A-423378.0 on the extrinsic cell death pathway through activation of TRAIL and its signalling pathway indicate that A-423378.0 may be a potent new therapeutic compound for the treatment of advanced colorectal cancer.

Noninvasive markers of liver fibrosis: on-treatment changes of serum markers predict the outcome of antifibrotic therapy.

AIM: The utility of noninvasive serum markers to longitudinally monitor liver fibrosis is not established. METHODS: A total of 70 patients with chronic hepatitis C who had previously failed antiviral therapy were randomized to receive pegylated interferon with or without silymarin for 24 months. Enhanced Liver Fibrosis (ELF) tests (hyularonic acid, terminal peptide of procollagen III, tissue inhibitor of matrix metaloproteinase-1) were performed on patient sera obtained before, during and at the end of the study (0, 12, 24 months) and liver histology obtained before and at the end of the study. RESULTS: At 24 months, absolute changes in Ishak fibrosis stage and ELF ranged from -4 to +4 and from -2.41 to +2.68, respectively. Absolute changes in ELF at 12 months were significantly associated with changes in both ELF and histology at 24 months. A model combining both baseline ELF and change of ELF at 12 months could predict the 24-month ELF (R=0.609, P<1×10), a decrease in ELF at 24 months [area under the curve (AUC): 0.80-0.85] and an increase in ELF at 24 months (AUC: 0.81-0.85). Furthermore, a model combining both baseline histologic stage and ELF together with the change of ELF at 12 months could predict 24-month histology (R=0.601, P<1×10, AUC: 0.88-0.92), histologic fibrosis regression (AUC: 0.81-0.84) and progression (AUC: 0.86-0.91). CONCLUSION: Our observations suggest that a change in the serum marker ELF predicts changes in liver fibrosis over a longer period. These data support the use of ELF as a surrogate marker of liver fibrosis evolution in monitoring antifibrotic treatments, thus permitting 'response-guided' therapy by the early identification of patients who will benefit from prolonged treatment.

Gastrointestinal cancer - only a deregulation of stem cell differentiation? (Review).

Recent research on embryonic and adult stem cells questions the currently accepted models of multi-step carcinogenesis in solid cancer. Accordingly, differentiated epithelial cells are considered to be the main target for mutational steps, leading to a growth and survival advantage of malignantly transformed cells. In contrast, the stem cell model of carcinogenesis emphasizes the role of stem cells as the initiating structure for tumor development. Yet, it is unclear if tumors contain dysregulated (embryonic) stem cells or if tumors consist of differentiated adult cells that obtained a de-differentiated stem cell-like phenotype. Here, we review the current knowledge on the roles of stem cells in gastrointestinal cancer formation and the implication on future diagnostic and therapeutic strategies.

The histone-deacetylase inhibitor SAHA potentiates proapoptotic effects of 5-fluorouracil and irinotecan in hepatoma cells.

Treatment for advanced stages of hepatocellular carcinoma (HCC) remains unsatisfactory. While 5-fluorouracil (5-FU) and irinotecan are first-line treatment options for other gastrointestinal tumors, their effect on HCCs is low. Histone-deacetylase inhibitors such as suberoylanilide hydroxamic acid (SAHA) have shown antitumoral activity at micromolar concentrations in a variety of human cancers in vitro and in vivo. Here, we investigated the effects of a combination of 5-FU, irinotecan and SAHA on growth inhibition and apoptosis induction in HCC cell lines. HepG2, Hep1B and MH-7777A hepatoma cell lines and human foreskin fibroblasts as non-transformed controls were incubated with 5-FU, irinotecan and SAHA either alone or in combination. While the single agents did not show any effects on growth of the cell lines, the combination of 5-FU and irinotecan (both 10 microM) led to a moderate increase in apoptosis and proliferation inhibition. Adding 1 microM SAHA increased the apoptosis rate in hepatoma cell lines up to 92% after 72 h, while fibroblasts showed no response (5.5% apoptosis). Induction of apoptosis was paralleled by loss of the mitochondrial transmembrane potential, downregulation of bcl-2 expression and activation of caspase 3 but not caspase 8. In summary, SAHA sensitized HCC cell lines for treatment with an otherwise ineffective combination of 5-FU and irinotecan and led to mitochondrial apoptosis induction. The use of the triple combination could optimize treatment results in vivo and needs further evaluation.

Improvement of quantitative testing of liver function in patients with chronic hepatitis C after installment of antiviral therapy.

AIM: To investigate if and to what extent antiviral therapy influenced a broad panel of quantitative testing of liver function (QTLF). METHODS: Fifty patients with chronic hepatitis C were either treated with interferon (n = 8), interferon/ribavirin (n = 19) or peg-interferon/ribavirin (n = 23). Quantitative testing of liver function, including aminopyrine breath test (ABT), galactose elimination capacity (GEC), sorbitol clearance (SCl) and indocyanine green clearance (ICG) was performed before and 3 mo after initiation of antiviral therapy. RESULTS: After 3 mo of antiviral treatment, 36 patients showed normal transaminases and were negative for HCV-RNA, 14 patients did not respond to therapy. ABT and GEC as parameters of microsomal and cytosolic liver function were reduced in all patients before therapy initiation and returned to normal values in the 36 therapy responders after 3 mo. Parameters of liver perfusion (SCl and ICG) were not affected by antiviral therapy. In the 14 non-responders, no changes in QTLF values were observed during the treatment period. CONCLUSION: ICG and SCl remained unaffected in patients with chronic hepatitis C, while ABT and GEC were significantly compromised. ABT and GEC normalized in responders to antiviral therapy. Early determination of ABT and GEC may differentiate responders from non-responders to antiviral treatment in hepatitis C.