Antibody targeting of surface P-selectin glycoprotein ligand 1 leads to lymphoma apoptosis and tumorigenesis inhibition.

Lymphomas are a heterogeneous group of diseases that originate from T, B or natural killer cells. Lymphoma treatment is based on chemotherapy, radiotherapy, and monoclonal antibody (mAb) or other immunotherapies. The P-selectin glycoprotein ligand 1 (PSGL-1) is expressed at the surface of hematological malignant cells and has been shown to have a pro-oncogenic role in multiple myeloma and lymphoma. Here, we investigated the expression and therapeutic potential of PSGL-1 in T and B cell lymphomas. By flow cytometry analysis, we found that PSGL-1 was expressed in both T and B cell-derived lymphoma cell lines but generally at higher levels in T cell lymphoma cell lines. For most T and B cell-derived lymphoma cell lines, in vitro targeting with the PL1 mAb, which recognizes the PSGL-1 N-terminal extracellular region and blocks functional interactions with selectins, resulted in reduced cell viability. The PL1 mAb pro-apoptotic activity was shown to be dose-dependent, to be linked to increased ERK kinase phosphorylation, and to be dependent on the MAP kinase signaling pathway. Importantly, anti-PSGL-1 treatment of mice xenografted with the HUT-78 cutaneous T-cell lymphoma cell line resulted in decreased tumor growth, had no effect on in vivo proliferation, but increased the levels of apoptosis in tumors. Anti-PSGL-1 treatment of mice xenografted with a Burkitt lymphoma cell line that was resistant to anti-PSGL-1 treatment in vitro, had no impact on tumorigenesis. These findings show that PSGL-1 antibody targeting triggers lymphoma cell apoptosis and substantiates PSGL-1 as a potential target for lymphoma therapy.

P-selectin glycoprotein ligand 1 promotes T cell lymphoma development and dissemination.

P-selectin glycoprotein ligand-1 (PSGL-1) is a membrane-bound glycoprotein expressed in lymphoid and myeloid cells. It is a ligand of P-, E- and L-selectin and is involved in T cell trafficking and homing to lymphoid tissues, among other functions. PSGL-1 expression has been implicated in different lymphoid malignancies, so here we aimed to evaluate the involvement of PSGL-1 in T cell lymphomagenesis and dissemination. PSGL-1 was highly expressed at the surface of human and mouse T cell leukemia and lymphoma cell lines. To assess its impact on T cell malignancies, we stably expressed human PSGL-1 (hPSGL-1) in a mouse thymic lymphoma cell line, which expresses low levels of endogenous PSGL-1 at the cell surface. hPSGL-1-expressing lymphoma cells developed subcutaneous tumors in athymic nude mice recipients faster than control empty vector or parental cells. Moreover, the kidneys, lungs and liver of tumor-bearing mice were infiltrated by hPSGL-1-expressing malignant T cells. To evaluate the role of PSGL-1 in lymphoma cell dissemination, we injected intravenously control and hPSGL-1-expressing lymphoma cells in athymic mice. Strikingly, PSGL-1 expression facilitated disease infiltration of the kidneys, as determined by histological analysis and anti-CD3 immunohistochemistry. Together, these results indicate that PSGL-1 expression promotes T cell lymphoma development and dissemination to different organs.

Event-driven processing for hardware-efficient neural spike sorting.

OBJECTIVE: The prospect of real-time and on-node spike sorting provides a genuine opportunity to push the envelope of large-scale integrated neural recording systems. In such systems the hardware resources, power requirements and data bandwidth increase linearly with channel count. Event-based (or data-driven) processing can provide here a new efficient means for hardware implementation that is completely activity dependant. In this work, we investigate using continuous-time level-crossing sampling for efficient data representation and subsequent spike processing. APPROACH: (1) We first compare signals (synthetic neural datasets) encoded with this technique against conventional sampling. (2) We then show how such a representation can be directly exploited by extracting simple time domain features from the bitstream to perform neural spike sorting. (3) The proposed method is implemented in a low power FPGA platform to demonstrate its hardware viability. MAIN RESULTS: It is observed that considerably lower data rates are achievable when using 7 bits or less to represent the signals, whilst maintaining the signal fidelity. Results obtained using both MATLAB and reconfigurable logic hardware (FPGA) indicate that feature extraction and spike sorting accuracies can be achieved with comparable or better accuracy than reference methods whilst also requiring relatively low hardware resources. SIGNIFICANCE: By effectively exploiting continuous-time data representation, neural signal processing can be achieved in a completely event-driven manner, reducing both the required resources (memory, complexity) and computations (operations). This will see future large-scale neural systems integrating on-node processing in real-time hardware.

Latent Class Analysis of Noninvasive Methods and Liver Biopsy in Chronic Hepatitis C: An Approach without a Gold Standard.

AIMS: To evaluate the applicability of the Latent Class Analysis (LCA) and accuracy of transient elastography (TE), aspartate-to-platelet-ratio-index (APRI), enhanced liver fibrosis (ELF), and liver biopsy (LB) for liver fibrosis assessment in a model without a gold standard. METHODS: Significant fibrosis was defined as TE ≥ 7.1 kPa, APRI ≥ 1.5, ELF ≥ 9.37, or LB METAVIR F ≥ 2. Cirrhosis was defined as TE ≥ 12.5 kPa, APRI ≥ 2.0, ELF ≥ 10.31, or LB as METAVIR F = 4. RESULTS: 117 patients with chronic hepatitis C were included. In the LCA, for significant fibrosis the sensitivities and specificities (95% CI) were 0.92 (0.86-0.98) and 0.79 (0.72-0.86) for TE; 0.47 (0.40-0.54) and 0.99 (0.95-1.00) for APRI; 0.81 (0.74-0.88) and 0.78 (0.71-0.85) for ELF; and 0.86 (0.68-1.00) and 0.91 (0.79-1.00) for LB. For cirrhosis, the sensitivities and specificities were 0.92 (0.76-1.00) and 0.94 (0.91-0.97) for TE; 0.57 (0.37-0.77) and 0.97 (0.93-1.00) for APRI; 0.94 (0.84-1.00) and 0.88 (0.82-0.94) for ELF; and 0.30 (0.12-0.48) and 1.00 for LB. CONCLUSION: LCA was useful to evaluate accuracy of methods for liver fibrosis staging. Sensitivities and specificities of noninvasive methods were increased in LCA compared to the use of LB as the gold standard.

Transient elastography evaluation of hepatic and spleen stiffness in patients with hepatosplenic schistosomiasis.

BACKGROUND: Hepatosplenic schistosomiasis (HES) has not been evaluated by transient elastography so far and its correlation with ultrasound variables remains to be defined. AIMS: The aim of this study was to describe the parameters of liver and spleen stiffness in HES assessed by transient elastography in comparison with cirrhotics and controls evaluating its correlation with ultrasonographic data. PATIENTS AND METHODS: HES, hepatitis C virus-cirrhotic, and control patients were included in this sectional study. Liver and spleen stiffness were compared among the three groups. The ultrasonographic parameters were compared with transient elastography in HES patients. RESULTS: Thirty HES, 30 hepatitis C virus-cirrhotic patients, and 17 controls were included. Those with HES presented liver stiffness that was significantly higher than the controls and lower than the cirrhotics: 9.7 (3.6-75.0) versus 3.7 (2.8-5.4) versus 27.0 (14.7-61.5) kPa (P<0.001). Spleen stiffness values were comparable between hepatosplenic and cirrhotics: 66.4 (25.7-75.0) versus 69.1 (18.0-75.0) kPa (P=0.78) and were significantly higher than the controls 16.5 kPa (6.3-34.3) (P<0.001). In patients with HES, high spleen stiffness was associated with right liver lobe diameter (P=0.015), splenic artery resistance index (P=0.002), portal vein diameter (P=0.021), portal vein area (P=0.008), portal vein congestion index (P=0.035), splenic vein diameter (P=0.013), and spleen diameter (P=0.021). CONCLUSION: Liver stiffness may be a useful tool to differentiate portal hypertension related to cirrhosis from that of HES. High spleen stiffness is a potential surrogate marker of portal hypertension in this population.

Enhanced liver fibrosis panel as a predictor of liver fibrosis in chronic hepatitis C patients.

BACKGROUND: Evaluation of fibrosis is crucial in the assessment of chronic hepatitis C (CHC). The enhanced liver fibrosis (ELF) is a serological panel including hyaluronic acid (HA), tissue inhibitor of matrix metalloproteinases-1 (TIMP-1), and amino-terminal propeptide of type III procollagen (PIIINP) that has shown good results in predicting liver fibrosis in distinct scenarios of chronic liver diseases. AIMS: We aimed to assess the performance of ELF on the detection of fibrosis and cirrhosis in a CHC patient cohort and to compare the results of ELF and transient elastography (TE-Fibroscan) using liver biopsy as reference. PATIENTS AND METHODS: One hundred twenty patients were prospectively evaluated by TE and ELF using an ADVIA Centaur automated system. The ELF score was calculated using the manufacturer's algorithm. Biopsies were classified according to the METAVIR score. Receiver operator characteristic curve analyses were performed to evaluate the accuracy of ELF and TE. RESULTS: The area under the receiver operator characteristic curve (AUROC) of ELF for the diagnosis of significant fibrosis was 0.81 [95% confidence interval (CI), 0.73-0.87], for advanced fibrosis was 0.82 (95% CI, 0.74-0.88), and for cirrhosis was 0.78 (95% CI, 0.70-0.85). Using the proposed cutoffs, ELF overestimated fibrosis in 66% (81/120) of cases and underestimated in 3% (3/120). We found no statistically significant difference when comparing the AUROC of ELF and TE for diagnosing fibrosis or cirrhosis. CONCLUSIONS: ELF panel is a good noninvasive fibrosis marker and showed similar results to TE in CHC patients. However, new cutoff points need to be established to improve its performance on patients with CHC.