49 results on '"Sek K"'
Search Results
2. FOXO1 enhances CAR T cell stemness, metabolic fitness and efficacy
- Author
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Chan, JD, Scheffler, CM, Munoz, I, Sek, K, Lee, JN, Huang, Y-K, Yap, KM, Saw, NYL, Li, J, Chen, AXY, Chan, CW, Derrick, EB, Todd, KL, Tong, J, Dunbar, PA, Hoang, TX, de Menezes, MN, Petley, EV, Kim, JS, Nguyen, D, Leung, PSK, So, J, Deguit, C, Zhu, J, House, IG, Kats, LM, Scott, AM, Solomon, BJ, Harrison, SJ, Oliaro, J, Parish, IA, Quinn, KM, Neeson, PJ, Slaney, CY, Lai, J, Beavis, PA, Darcy, PK, Chan, JD, Scheffler, CM, Munoz, I, Sek, K, Lee, JN, Huang, Y-K, Yap, KM, Saw, NYL, Li, J, Chen, AXY, Chan, CW, Derrick, EB, Todd, KL, Tong, J, Dunbar, PA, Hoang, TX, de Menezes, MN, Petley, EV, Kim, JS, Nguyen, D, Leung, PSK, So, J, Deguit, C, Zhu, J, House, IG, Kats, LM, Scott, AM, Solomon, BJ, Harrison, SJ, Oliaro, J, Parish, IA, Quinn, KM, Neeson, PJ, Slaney, CY, Lai, J, Beavis, PA, and Darcy, PK
- Abstract
Chimeric antigen receptor (CAR) T cell therapy has transformed the treatment of haematological malignancies such as acute lymphoblastic leukaemia, B cell lymphoma and multiple myeloma1,2,3,4, but the efficacy of CAR T cell therapy in solid tumours has been limited5. This is owing to a number of factors, including the immunosuppressive tumour microenvironment that gives rise to poorly persisting and metabolically dysfunctional T cells. Analysis of anti-CD19 CAR T cells used clinically has shown that positive treatment outcomes are associated with a more ‘stem-like’ phenotype and increased mitochondrial mass6,7,8. We therefore sought to identify transcription factors that could enhance CAR T cell fitness and efficacy against solid tumours. Here we show that overexpression of FOXO1 promotes a stem-like phenotype in CAR T cells derived from either healthy human donors or patients, which correlates with improved mitochondrial fitness, persistence and therapeutic efficacy in vivo. This work thus reveals an engineering approach to genetically enforce a favourable metabolic phenotype that has high translational potential to improve the efficacy of CAR T cells against solid tumours.
- Published
- 2024
3. Immunotherapy: IMPROVING CAR T CELL EFFICACY IN A PRECLINICAL MODEL OF BREAST CANCER THROUGH MODIFIED MANUFACTURING METHODS AND ADJUVANT THERAPY
- Author
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Li, J., primary, Tong, J., additional, Sek, K., additional, Yatomi-Clarke, S., additional, Sebti, S., additional, Lim, R., additional, and Darcy, P., additional
- Published
- 2023
- Full Text
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4. Immunotherapy: OMNI-CAR, A UNIVERSAL CAR T CELL THERAPY UTILIZING COVALENT SPYTAG/SPYCATCHER BINDING TO TARGET MULTIPLE ANTIGENS IN DIFFERENT TUMORS
- Author
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Sek, K., primary, Li, J., additional, Tong, J., additional, Lim, R., additional, Yatomi-Clarke, S., additional, and Darcy, P., additional
- Published
- 2023
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5. CRISPR-Cas9 screening identifies an IRF1-SOCS1-mediated negative feedback loop that limits CXCL9 expression and antitumor immunity
- Author
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House, IG, Derrick, EB, Sek, K, Chen, AXY, Li, J, Lai, J, Todd, KL, Munoz, I, Michie, J, Chan, CW, Huang, Y-K, Chan, JD, Petley, E, Tong, J, Nguyen, D, Engel, S, Savas, P, Hogg, SJ, Vervoort, SJ, Kearney, CJ, Burr, ML, Lam, EYN, Gilan, O, Bedoui, S, Johnstone, RW, Dawson, MA, Loi, S, Darcy, PK, Beavis, PA, House, IG, Derrick, EB, Sek, K, Chen, AXY, Li, J, Lai, J, Todd, KL, Munoz, I, Michie, J, Chan, CW, Huang, Y-K, Chan, JD, Petley, E, Tong, J, Nguyen, D, Engel, S, Savas, P, Hogg, SJ, Vervoort, SJ, Kearney, CJ, Burr, ML, Lam, EYN, Gilan, O, Bedoui, S, Johnstone, RW, Dawson, MA, Loi, S, Darcy, PK, and Beavis, PA
- Abstract
CXCL9 expression is a strong predictor of response to immune checkpoint blockade therapy. Accordingly, we sought to develop therapeutic strategies to enhance the expression of CXCL9 and augment antitumor immunity. To perform whole-genome CRISPR-Cas9 screening for regulators of CXCL9 expression, a CXCL9-GFP reporter line is generated using a CRISPR knockin strategy. This approach finds that IRF1 limits CXCL9 expression in both tumor cells and primary myeloid cells through induction of SOCS1, which subsequently limits STAT1 signaling. Thus, we identify a subset of STAT1-dependent genes that do not require IRF1 for their transcription, including CXCL9. Targeting of either IRF1 or SOCS1 potently enhances CXCL9 expression by intratumoral macrophages, which is further enhanced in the context of immune checkpoint blockade therapy. We hence show a non-canonical role for IRF1 in limiting the expression of a subset of STAT1-dependent genes through induction of SOCS1.
- Published
- 2023
6. PTP1B Is an Intracellular Checkpoint that Limits T- cell and CAR T- cell Antitumor Immunity
- Author
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Wiede, F, Lu, K-H, Du, X, Zeissig, MN, Xu, R, Goh, PK, Xirouchaki, CE, Hogarth, SJ, Greatorex, S, Sek, K, Daly, RJ, Beavis, PA, Darcy, PK, Tonks, NK, Tiganis, T, Wiede, F, Lu, K-H, Du, X, Zeissig, MN, Xu, R, Goh, PK, Xirouchaki, CE, Hogarth, SJ, Greatorex, S, Sek, K, Daly, RJ, Beavis, PA, Darcy, PK, Tonks, NK, and Tiganis, T
- Abstract
UNLABELLED: Immunotherapies aimed at alleviating the inhibitory constraints on T cells have revolutionized cancer management. To date, these have focused on the blockade of cell-surface checkpoints such as PD-1. Herein we identify protein tyrosine phosphatase 1B (PTP1B) as an intracellular checkpoint that is upregulated in T cells in tumors. We show that increased PTP1B limits T-cell expansion and cytotoxicity to contribute to tumor growth. T cell-specific PTP1B deletion increased STAT5 signaling, and this enhanced the antigen-induced expansion and cytotoxicity of CD8+ T cells to suppress tumor growth. The pharmacologic inhibition of PTP1B recapitulated the T cell-mediated repression of tumor growth and enhanced the response to PD-1 blockade. Furthermore, the deletion or inhibition of PTP1B enhanced the efficacy of adoptively transferred chimeric antigen receptor (CAR) T cells against solid tumors. Our findings identify PTP1B as an intracellular checkpoint whose inhibition can alleviate the inhibitory constraints on T cells and CAR T cells to combat cancer. SIGNIFICANCE: Tumors subvert antitumor immunity by engaging checkpoints that promote T-cell exhaustion. Here we identify PTP1B as an intracellular checkpoint and therapeutic target. We show that PTP1B is upregulated in intratumoral T cells and that its deletion or inhibition enhances T-cell antitumor activity and increases CAR T-cell effectiveness against solid tumors. This article is highlighted in the In This Issue feature, p. 587.
- Published
- 2022
7. A comparison of striatal-to-occipital ratio quantification approaches in F-FDOPA pet imaging
- Author
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Pulford, R., Loh, N., Sek, K., Culleton, S., Hagan, T., Jacques, A., Francis, R., Pulford, R., Loh, N., Sek, K., Culleton, S., Hagan, T., Jacques, A., and Francis, R.
- Abstract
Background. Parkinson's disease (PD) can be challenging to diagnose in the clinical setting. 6-[18F] fluoro-L-3,4-dihydroxyphenylalanine (18F-FDOPA) PET imaging may assist in the diagnosis of Parkinson's disease by assessing pre-synaptic dopamine dysfunction. The striato-occipital ratio (SOR) is a measure of the uptake in the striatum (caudate and putamen) referenced against the activity in the occipital lobe (representing background activity). Manual quantification of these regions of interest (ROI) is commonly performed however this is time-consuming and may be susceptible to variances in inter-reader interpretation. Aims. The aim of this audit was to compare manual quantification of 18F-FDOPA PET SOR, performed as standard practice at our institution, to a commercially available automated SOR quantification program. Methods. The scans of 95 consecutive patients (40 female, 55 male, 59.77 ± 15.26 years) who underwent 18F-DOPA PET imaging for evaluation of Parkinsonism were retrospectively reviewed. Each PET scan was analysed using manual quantification by two Nuclear Medicine consultants, and the mean of these sets of quantitative values was compared against the automated quantification generated via Siemens SyngoVia software package MI-Neurology. This study has institutional approval as a Quality Initiative project. Results. 90 scans were evaluable by both manual and automated methods. Five patients who were unable to undergo automated quantitative analysis due to either inadequate image times or administrative errors were excluded from the comparative analysis. Statistical analysis comparing SOR obtained by manual and automated methods demonstrated high intraclass correlation (ICC), with minimal variance (Table 1). Conclusion. Automated quantification of SOR demonstrated statistically significant agreement with manual quantification methods highlighting its potential to be utilised to increase efficiency in 18F-FDOPA PET imaging interpretation.
- Published
- 2021
8. EARLY-PHENOTYPE LEWIS Y CAR-T CELLS PERSIST BETTER IN VIVO AND INDUCE SOLID TUMOR REGRESSION IN COMBINATION WITH ANTI-PD1
- Author
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Meyran, D, Zhu, J, Butler, J, Macdonald, S, Tantalo, D, Thio, N, Sek, K, Ekert, P, Kershaw, M, Trapani, J, Darcy, P, Neeson, P, Meyran, D, Zhu, J, Butler, J, Macdonald, S, Tantalo, D, Thio, N, Sek, K, Ekert, P, Kershaw, M, Trapani, J, Darcy, P, and Neeson, P
- Abstract
Background Chimeric antigen receptor (CAR-T) cells are a promising new therapy for patients with cancer. However, in contrast to their success in B cell malignancies, CAR-T cells targeting solid cancers have had limited success so far due to their poor proliferation and poor long-term persistence in vivo. To address this issue, we used naïve T cells to generate second-generation CAR-T cells recognizing the tumor antigen Lewis Y (LeY), termed ‘early’ CAR-T cells. Methods Purified naïve T cells were activated by CD3/CD28 soluble tetrameric antibody complex, retrovirally transduced (LeY scFv-CD3z-CD28 CAR) and expanded in IL-7/IL-15. The early LeY CAR-T cell function was tested in vitro for cytotoxicity (Cr-release and degranulation), proliferation, and cytokine secretion by CBA, either de novo or following chronic stimulation for 1 month. Finally, early CAR-T cell persistence and anti-tumor efficacy was assessed in the OVCAR3-NSG model, in the presence or absence of anti-PD-1. Results The early-CAR-T cells comprised stem cell memory-like (CD95+, CD62L+, CD45RA+) and central memory phenotype (CD95+, CD62L+, CD45RA-) T cells with increased expression of ICOS, Ki67, TCF7 and CD27 (Figure 1). The early-CAR-T cells retained potent antigen-specific cytotoxicity, and secreted significantly higher levels of cytokines (IFN-?, TNF-a and IL-2) and increased proliferation compared to conventional CAR-T cells. Importantly, early-CAR-T cells had a significantly higher proliferative capacity after long-term chronic stimulation compared to conventional CAR-T cells (figure 2), and CD4+ CAR-T cells were critical for effective early CD8+ CAR-T cell proliferation capacity in vitro (figure 3). Early CAR-T cells had significantly better in vivo tumor control compared to conventional CAR-T cells (Figure 4), this was associated with increased CAR-T cell persistence. Because chronically stimulated early-LeY-CAR-T cells expressed PD-1 (figure 2), and OVCAR-3 cells expressed PD-L1 when co-cultu
- Published
- 2020
9. IL-15 Preconditioning Augments CAR T Cell Responses to Checkpoint Blockade for Improved Treatment of Solid Tumors
- Author
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Giuffrida, L, Sek, K, Henderson, MA, House, IG, Lai, J, Chen, AXY, Todd, KL, Petley, E, Mardiana, S, Todorovski, I, Gruber, E, Kelly, MJ, Solomon, BJ, Vervoort, SJ, Johnstone, RW, Parish, IA, Neeson, PJ, Kats, LM, Darcy, PK, Beavis, PA, Giuffrida, L, Sek, K, Henderson, MA, House, IG, Lai, J, Chen, AXY, Todd, KL, Petley, E, Mardiana, S, Todorovski, I, Gruber, E, Kelly, MJ, Solomon, BJ, Vervoort, SJ, Johnstone, RW, Parish, IA, Neeson, PJ, Kats, LM, Darcy, PK, and Beavis, PA
- Abstract
Chimeric antigen receptor (CAR) T cell therapy has been highly successful in hematological malignancies leading to their US Food and Drug Administration (FDA) approval. However, the efficacy of CAR T cells in solid tumors is limited by tumor-induced immunosuppression, leading to the development of combination approaches, such as adjuvant programmed cell death 1 (PD-1) blockade. Current FDA-approved methods for generating CAR T cells utilize either anti-CD3 and interleukin (IL)-2 or anti-CD3/CD28 beads, which can generate a T cell product with an effector/exhausted phenotype. Whereas different cytokine preconditioning milieu, such as IL-7/IL-15, have been shown to promote T cell engraftment, the impact of this approach on CAR T cell responses to adjuvant immune-checkpoint blockade has not been assessed. In the current study, we reveal that the preconditioning of CAR T cells with IL-7/IL-15 increased CAR T cell responses to anti-PD-1 adjuvant therapy. This was associated with the emergence of an intratumoral CD8+CD62L+TCF7+IRF4- population that was highly responsive to anti-PD-1 therapy and mediated the vast majority of transcriptional and epigenetic changes in vivo following PD-1 blockade. Our data indicate that preservation of CAR T cells in a TCF7+ phenotype is crucial for their responsiveness to adjuvant immunotherapy approaches and should be a key consideration when designing clinical protocols.
- Published
- 2020
10. THE DIAGNOSTIC UTILITY OF I-123 METAIODOBENZYLGUANIDINEE (MIBG) SCINTIGRAPHY IN DIFFERENTIATING PARKINSONʼS DISEASE FROM OTHER FORMS OF PARKINSONISM: O37
- Author
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Sek, K, Loh, N, Kwan, K, and Vieira, B
- Published
- 2012
11. Targeting Adenosine Receptor Signaling in Cancer Immunotherapy
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Sek, K, Molck, C, Stewart, GD, Kats, L, Darcy, PK, Beavis, PA, Sek, K, Molck, C, Stewart, GD, Kats, L, Darcy, PK, and Beavis, PA
- Abstract
The immune system plays a major role in the surveillance and control of malignant cells, with the presence of tumor infiltrating lymphocytes (TILs) correlating with better patient prognosis in multiple tumor types. The development of 'checkpoint blockade' and adoptive cellular therapy has revolutionized the landscape of cancer treatment and highlights the potential of utilizing the patient's own immune system to eradicate cancer. One mechanism of tumor-mediated immunosuppression that has gained attention as a potential therapeutic target is the purinergic signaling axis, whereby the production of the purine nucleoside adenosine in the tumor microenvironment can potently suppress T and NK cell function. The production of extracellular adenosine is mediated by the cell surface ectoenzymes CD73, CD39, and CD38 and therapeutic agents have been developed to target these as well as the downstream adenosine receptors (A₁R, A2AR, A2BR, A₃R) to enhance anti-tumor immune responses. This review will discuss the role of adenosine and adenosine receptor signaling in tumor and immune cells with a focus on their cell-specific function and their potential as targets in cancer immunotherapy.
- Published
- 2018
12. Targeting the adenosine 2A receptor enhances chimeric antigen receptor T cell efficacy
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Beavis, PA, Henderson, MA, Giuffrida, L, Mills, JK, Sek, K, Cross, RS, Davenport, AJ, John, Liza B, Mardiana, S, Slaney, CY, Johnstone, RW, Trapani, JA, Stagg, J, Loi, S, Kats, L, Gyorki, D, Kershaw, MH, Darcy, PK, Beavis, PA, Henderson, MA, Giuffrida, L, Mills, JK, Sek, K, Cross, RS, Davenport, AJ, John, Liza B, Mardiana, S, Slaney, CY, Johnstone, RW, Trapani, JA, Stagg, J, Loi, S, Kats, L, Gyorki, D, Kershaw, MH, and Darcy, PK
- Published
- 2017
13. Mapping Patterns of Regional Nodal Recurrence After Treatment in Breast Cancer Patients: Evaluation of the RTOG Breast Cancer Atlas
- Author
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Beaton, L.E., primary, Nica, L., additional, Ayre, G., additional, Sek, K., additional, Aparicio, M., additional, Gondara, L., additional, Speers, C., additional, Tyldesley, S., additional, and Nichol, A., additional
- Published
- 2017
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14. EP-1195: Regional nodal recurrences after adjuvant breast radiotherapy - are we covering the target?
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Beaton, L.E., primary, Nica, L., additional, Sek, K., additional, Ayers, G., additional, Speers, C., additional, Tyldesley, S., additional, and Nichol, A., additional
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- 2017
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15. Reaction Delay of Aluminum in Condensed Explosives
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Chan, Sek K., primary
- Published
- 2014
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16. A Haemostatic Agent Delivery System for Endoscopic Neurosurgical Procedures
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Waran, V., additional, Sek, K., additional, Bahuri, N., additional, Narayanan, P., additional, and Chandran, H., additional
- Published
- 2011
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17. Effect of oil price pass-through on domestic price inflation: Evidence from nonlinear ARDL models
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Sek Kun Siok
- Subjects
Inflation ,Oil price ,Asymmetric effects ,Nonlinear ARDL models ,Economic theory. Demography ,HB1-3840 - Abstract
We intended to demonstrate that oil price can have a different passthrough effect into domestic prices at consumer and production levels subject to an oil dependency factor. The results were compared between oil-importing and oil-exporting countries. The nonlinear autoregressive distributed lags (NARDL) models were used to capture the asymmetric pass-through effects of oil price increases and decreases in consumer price and producer price respectively. Our results revealed that oil price changes can have asymmetric effect on consumer price index (CPI) inflation directly and indirectly with more influential impact of indirect effect. This result holds for both groups of countries. The effect on producer price is much larger especially in oil-importing group due to the high dependence of these countries on oil. Oil price changes did lead to increases in consumer prices in oil-importing countries. This may due to effective monetary policy that enhances price stickiness in the economy.
- Published
- 2019
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18. An exome array study of the plasma metabolome
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Eugene P. Rhee, Qiong Yang, Bing Yu, Xuan Liu, Susan Cheng, Amy Deik, Kerry A. Pierce, Kevin Bullock, Jennifer E. Ho, Daniel Levy, Jose C. Florez, Sek Kathiresan, Martin G. Larson, Ramachandran S. Vasan, Clary B. Clish, Thomas J. Wang, Eric Boerwinkle, Christopher J. O’Donnell, and Robert E. Gerszten
- Subjects
Science - Abstract
Several GWAS have identified many common variants associated with blood metabolites. Here, the authors use an exome array to identify low frequency, potentially functional variants that impact human metabolism.
- Published
- 2016
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19. Does inflation targeting work in emerging East-Asian economies?
- Author
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Sek Kun Siok and Har Mun Wai
- Subjects
disinflation cost ,inflation targeting ,macroeconomics ,trade-off ,monetary policy ,Economic theory. Demography ,HB1-3840 - Abstract
This paper evaluates on the performance of the inflation-targeting regime in three emerging East-Asian economies that have experienced changes in monetary policy regimes, from rigidities to a flexible exchange rate and inflation targeting, after the financial crisis of 1997-98. In particular, the evaluation focuses on the inter-relationship between inflation and the output growth/gap in these emerging economies between the pre- and post-inflation targeting periods. A bivariate GARCH (1,1) model is applied. The results reveal lower variability in inflation and output growth after the implementation of the inflation targeting regime. The persistency of inflation and output also decline. The study finds no evidence of greater disinflation cost experienced in these economies after the implementation of the inflation-targeting regime. Overall, the results imply that inflation targeting works well in these emerging markets.
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- 2012
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20. Melaminium nitrate–melamine–water (1/1/1)
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Farook Adam, Sek Kei Lin, Kasim Mohammed Hello, Madhukar Hemamalini, and Hoong-Kun Fun
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Crystallography ,QD901-999 - Abstract
In the crystal structure of the title salt, C3H7N6+·NO3−·C3H6N6·H2O, the asymmetric unit consists of two neutral melamine (1,3,5-triazine-2,4,6-triamine) molecules, two melaminium cations, two nitrate anions and two solvent water molecules. One of the nitrate anions is disordered over two sets of positions, with a refined occupancy ratio of 0.909 (3):0.091 (3). The cations and neutral molecules are approximately planar, with maximum deviations of 0.018 (2), 0.024 (2), 0.019 (2) and 0.007 (2) Å for each, respectively. In the crystal structure, melaminium cations and netural melamine molecules self-assemble via N—H...N hydrogen bonds to form a supramolecular hexagonal-shaped motif. In addition, the nitrate anions and water molecules are connected by N—H...O hydrogen bonds to form a three-dimensional network.
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- 2010
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21. Radiation Grafted Membranes
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Selmiye Alkan Gürsel, Lorenz Gubler, Bhuvanesh Gupta Gupta, Günther G. Scherer, Abe, A., Albertsson, A. C, Duncan, R, and Duˇsek, K
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Materials science ,Hydrogen ,Proton exchange membrane fuel cell ,chemistry.chemical_element ,Radiation ,Oxygen ,QD450-801 Physical and theoretical chemistry ,chemistry.chemical_compound ,Membrane ,chemistry ,Chemical engineering ,TP0155-156 Chemical engineering ,TP1080 Polymers and polymer manufacture ,Nafion ,Polymer chemistry ,Fuel cells ,Ionomer - Abstract
The development of proton-exchange membranes for fuel cells has generated global interest in order to have a potential source of power for stationary and portable applications. The membrane is the heart of a fuel cell and the performance of a fuel cell depends largely on the physico-chemical nature of the membrane and its stability in the hostile environment of hydrogen and oxygen at elevated temperatures. Efforts are being made to develop membranes that are similar to commercial Nafion membranes in performance and are available at an affordable price. The radiation grafting of styrene and its derivatives onto existing polymer films and subsequent sulfonation of the grafted films has been an attractive route for developing these membranes with requiredchemistry and properties. The process of radiation grafting offers enormous possibilities for design of the polymer architecture by careful variation of the irradiation and the grafting conditions. A wide range of crosslinkers are available, which introduce stability to the membrane during its operation in fuel cells. Crosslinking of the base polymer prior to grafting has also been an attractive means of obtaining membranes with better performance. A systematic presentation is made of the grafting process into different polymers,the physical properties of the resultant membranes, and the fuel cell application of these membranes.
- Published
- 2008
22. Intermittently scanned continuous glucose monitoring provides no benefit over structured self-monitoring of blood glucose in type 2 diabetes not on prandial insulin, in the context of diabetes self-management education: GLucose monitoring programme SingaporE (GLiMPSE).
- Author
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Rama Chandran S, Rahman N, Gandhi M, Tan NC, Phoon IKY, Seah DEJ, Cheah MH, Sek K, and Gardner DS
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- Humans, Middle Aged, Male, Female, Aged, Insulin therapeutic use, Insulin administration & dosage, Self-Management methods, Singapore, Patient Education as Topic methods, Adult, Glycemic Control methods, Continuous Glucose Monitoring, Diabetes Mellitus, Type 2 blood, Diabetes Mellitus, Type 2 drug therapy, Diabetes Mellitus, Type 2 therapy, Blood Glucose Self-Monitoring methods, Blood Glucose analysis, Glycated Hemoglobin analysis, Glycated Hemoglobin metabolism, Hypoglycemic Agents therapeutic use
- Abstract
Objective: We evaluated the impact of intermittently scanned continuous glucose monitoring(is-CGM)over self-monitoring of blood glucose(SMBG) in the context of diabetes self-management education (DSME) in sub-optimally controlled type 2 diabetes(T2D) in a multi-ethnicsetting., Research Design and Method: Randomized-controlled, open-label trial (NCT04564911), of T2D with HbA1c ≥ 7.5-≤10 %, on oral agents with/without basal insulin was carried out. Intervention arm received 6 weeks(w) continuous is-CGM, followed by one is-CGM/month till 24w. Control arm was advised to perform 4 SMBG/day. Educationwas delivered at weeks 0, 2, 8, 16., Primary Outcome: Change in HbA1c from baseline at 24w. Modified intention-to-treat (mITT) analysis with linear mixed-effect model for repeated measurementswas performed., Results: 176 subjects, age 55 ± 10.7 years(y), DM duration 11 ± 7.3y, BMI 27.8 ± 5.9 kg/m
2 , 58 % Male, 29.5 % basal insulin users were analysed. Within each arm,from baseline to 24w, mean HbA1c decreasedby -0.6 % (-6.6.mmol/mol, p-value < 0.01)and weight decreased(isCGM: -1.44 kg; SMBG: -1.25 kg, both p < 0.01). These changes were sustained to one year. However, there wasno significant difference in these parameters between arms (p-value > 0.05)., Conclusion: In the context of DSME, use of either SMBG or is-CGM led to improved glycaemia and reduced weight over a period of 24 weeks, sustained to one year., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [The study used Abbott glucose meters, is-CGM devices and the Freestyle Libre Pro sensors which were procured at cost for the purpose of carrying out the study. Abbott Diabetes Care did not have any influence over the study protocol, insight into data or analysis. SRC has participated on speaker bureaus with Abbott, Medtronic, Sanofi and Dexcom. DSLG has participated on speaker bureaus with Medtronic, Embecta, Dexcom, Sanofi and Roche. DSLG has been paid consultation fees from Dexcom and Embecta]., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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23. FOXO1 enhances CAR T cell stemness, metabolic fitness and efficacy.
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Chan JD, Scheffler CM, Munoz I, Sek K, Lee JN, Huang YK, Yap KM, Saw NYL, Li J, Chen AXY, Chan CW, Derrick EB, Todd KL, Tong J, Dunbar PA, Li J, Hoang TX, de Menezes MN, Petley EV, Kim JS, Nguyen D, Leung PSK, So J, Deguit C, Zhu J, House IG, Kats LM, Scott AM, Solomon BJ, Harrison SJ, Oliaro J, Parish IA, Quinn KM, Neeson PJ, Slaney CY, Lai J, Beavis PA, and Darcy PK
- Subjects
- Humans, Mice, Cell Line, Tumor, Mitochondria metabolism, Phenotype, Tumor Microenvironment immunology, Forkhead Box Protein O1 metabolism, Forkhead Box Protein O1 genetics, Immunotherapy, Adoptive, Receptors, Chimeric Antigen immunology, Receptors, Chimeric Antigen metabolism, T-Lymphocytes immunology, T-Lymphocytes metabolism, T-Lymphocytes cytology, Stem Cells cytology, Stem Cells immunology, Stem Cells metabolism, Neoplasms immunology, Neoplasms pathology, Neoplasms therapy
- Abstract
Chimeric antigen receptor (CAR) T cell therapy has transformed the treatment of haematological malignancies such as acute lymphoblastic leukaemia, B cell lymphoma and multiple myeloma
1-4 , but the efficacy of CAR T cell therapy in solid tumours has been limited5 . This is owing to a number of factors, including the immunosuppressive tumour microenvironment that gives rise to poorly persisting and metabolically dysfunctional T cells. Analysis of anti-CD19 CAR T cells used clinically has shown that positive treatment outcomes are associated with a more 'stem-like' phenotype and increased mitochondrial mass6-8 . We therefore sought to identify transcription factors that could enhance CAR T cell fitness and efficacy against solid tumours. Here we show that overexpression of FOXO1 promotes a stem-like phenotype in CAR T cells derived from either healthy human donors or patients, which correlates with improved mitochondrial fitness, persistence and therapeutic efficacy in vivo. This work thus reveals an engineering approach to genetically enforce a favourable metabolic phenotype that has high translational potential to improve the efficacy of CAR T cells against solid tumours., (© 2024. The Author(s).)- Published
- 2024
- Full Text
- View/download PDF
24. CRISPR-Cas9 screening identifies an IRF1-SOCS1-mediated negative feedback loop that limits CXCL9 expression and antitumor immunity.
- Author
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House IG, Derrick EB, Sek K, Chen AXY, Li J, Lai J, Todd KL, Munoz I, Michie J, Chan CW, Huang YK, Chan JD, Petley EV, Tong J, Nguyen D, Engel S, Savas P, Hogg SJ, Vervoort SJ, Kearney CJ, Burr ML, Lam EYN, Gilan O, Bedoui S, Johnstone RW, Dawson MA, Loi S, Darcy PK, and Beavis PA
- Published
- 2024
- Full Text
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25. A 2A R eGFP reporter mouse enables elucidation of A 2A R expression dynamics during anti-tumor immune responses.
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Todd KL, Lai J, Sek K, Huang YK, Newman DM, Derrick EB, Koay HF, Nguyen D, Hoang TX, Petley EV, Chan CW, Munoz I, House IG, Lee JN, Kim JS, Li J, Tong J, N de Menezes M, Scheffler CM, Yap KM, Chen AXY, Dunbar PA, Haugen B, Parish IA, Johnstone RW, Darcy PK, and Beavis PA
- Subjects
- Animals, Mice, Cytokines metabolism, Immunity, Immunotherapy, Lymphocytes, Tumor-Infiltrating, Tumor Microenvironment, Neoplasms genetics, Neoplasms metabolism
- Abstract
There is significant clinical interest in targeting adenosine-mediated immunosuppression, with several small molecule inhibitors having been developed for targeting the A
2A R receptor. Understanding of the mechanism by which A2A R is regulated has been hindered by difficulty in identifying the cell types that express A2A R due to a lack of robust antibodies for these receptors. To overcome this limitation, here an A2A R eGFP reporter mouse is developed, enabling the expression of A2A R during ongoing anti-tumor immune responses to be assessed. This reveals that A2A R is highly expressed on all tumor-infiltrating lymphocyte subsets including Natural Killer (NK) cells, NKT cells, γδ T cells, conventional CD4+ and CD8+ T lymphocytes and on a MHCIIhi CD86hi subset of type 2 conventional dendritic cells. In response to PD-L1 blockade, the emergence of PD-1+ A2A R- cells correlates with successful therapeutic responses, whilst IL-18 is identified as a cytokine that potently upregulates A2A R and synergizes with A2A R deficiency to improve anti-tumor immunity. These studies provide insight into the biology of A2A R in the context of anti-tumor immunity and reveals potential combination immunotherapy approaches., (© 2023. The Author(s).)- Published
- 2023
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26. CRISPR-Cas9 screening identifies an IRF1-SOCS1-mediated negative feedback loop that limits CXCL9 expression and antitumor immunity.
- Author
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House IG, Derrick EB, Sek K, Chen AXY, Li J, Lai J, Todd KL, Munoz I, Michie J, Chan CW, Huang YK, Chan JD, Petley EV, Tong J, Nguyen D, Engel S, Savas P, Hogg SJ, Vervoort SJ, Kearney CJ, Burr ML, Lam EYN, Gilan O, Bedoui S, Johnstone RW, Dawson MA, Loi S, Darcy PK, and Beavis PA
- Subjects
- Feedback, Suppressor of Cytokine Signaling Proteins genetics, Signal Transduction, CRISPR-Cas Systems, Immune Checkpoint Inhibitors
- Abstract
CXCL9 expression is a strong predictor of response to immune checkpoint blockade therapy. Accordingly, we sought to develop therapeutic strategies to enhance the expression of CXCL9 and augment antitumor immunity. To perform whole-genome CRISPR-Cas9 screening for regulators of CXCL9 expression, a CXCL9-GFP reporter line is generated using a CRISPR knockin strategy. This approach finds that IRF1 limits CXCL9 expression in both tumor cells and primary myeloid cells through induction of SOCS1, which subsequently limits STAT1 signaling. Thus, we identify a subset of STAT1-dependent genes that do not require IRF1 for their transcription, including CXCL9. Targeting of either IRF1 or SOCS1 potently enhances CXCL9 expression by intratumoral macrophages, which is further enhanced in the context of immune checkpoint blockade therapy. We hence show a non-canonical role for IRF1 in limiting the expression of a subset of STAT1-dependent genes through induction of SOCS1., Competing Interests: Declaration of interests P.A.B. declares the following conflicts: research funding from AstraZeneca, Bristol-Myers-Squibb, and Gilead Sciences. P.K.D. declares the following conflicts: research funding from Myeloid Therapeutics, Prescient Therapeutics, Bristol-Myers-Squibb, and Juno Therapeutics., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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27. Protein-losing enteropathy as a rare manifestation of systemic lupus erythematosus.
- Author
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Ng DM, Sek K, and Nossent J
- Subjects
- Humans, Protein-Losing Enteropathies diagnosis, Protein-Losing Enteropathies etiology, Lupus Erythematosus, Systemic complications, Lupus Erythematosus, Systemic diagnosis
- Abstract
Competing Interests: Competing interests: None declared.
- Published
- 2023
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28. T STEM -like CAR-T cells exhibit improved persistence and tumor control compared with conventional CAR-T cells in preclinical models.
- Author
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Meyran D, Zhu JJ, Butler J, Tantalo D, MacDonald S, Nguyen TN, Wang M, Thio N, D'Souza C, Qin VM, Slaney C, Harrison A, Sek K, Petrone P, Thia K, Giuffrida L, Scott AM, Terry RL, Tran B, Desai J, Prince HM, Harrison SJ, Beavis PA, Kershaw MH, Solomon B, Ekert PG, Trapani JA, Darcy PK, and Neeson PJ
- Subjects
- Humans, T-Lymphocytes, Cytokines metabolism, Stem Cells metabolism, Receptors, Antigen, T-Cell metabolism, Immunotherapy, Adoptive methods, Neoplasms
- Abstract
Patients who receive chimeric antigen receptor (CAR)-T cells that are enriched in memory T cells exhibit better disease control as a result of increased expansion and persistence of the CAR-T cells. Human memory T cells include stem-like CD8
+ memory T cell progenitors that can become either functional stem-like T (TSTEM ) cells or dysfunctional T progenitor exhausted (TPEX ) cells. To that end, we demonstrated that TSTEM cells were less abundant in infused CAR-T cell products in a phase 1 clinical trial testing Lewis Y-CAR-T cells (NCT03851146), and the infused CAR-T cells displayed poor persistence in patients. To address this issue, we developed a production protocol to generate TSTEM -like CAR-T cells enriched for expression of genes in cell replication pathways. Compared with conventional CAR-T cells, TSTEM -like CAR-T cells had enhanced proliferative capacity and increased cytokine secretion after CAR stimulation, including after chronic CAR stimulation in vitro. These responses were dependent on the presence of CD4+ T cells during TSTEM -like CAR-T cell production. Adoptive transfer of TSTEM -like CAR-T cells induced better control of established tumors and resistance to tumor rechallenge in preclinical models. These more favorable outcomes were associated with increased persistence of TSTEM -like CAR-T cells and an increased memory T cell pool. Last, TSTEM -like CAR-T cells and anti-programmed cell death protein 1 (PD-1) treatment eradicated established tumors, and this was associated with increased tumor-infiltrating CD8+ CAR+ T cells producing interferon-γ. In conclusion, our CAR-T cell protocol generated TSTEM -like CAR-T cells with enhanced therapeutic efficacy, resulting in increased proliferative capacity and persistence in vivo.- Published
- 2023
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29. 2021 Asia-Pacific Graves' Disease Consortium Survey of Clinical Practice Patterns in the Management of Graves' Disease.
- Author
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Parameswaran R, de Jong MC, Kit JLW, Sek K, Nam TQ, Thang TV, Khue NT, Aye TT, Tun PM, Cole T, Miller JA, Villa M, Khiewvan B, Sirinvaravong S, Sin YL, Muhammad R, Jap TS, Agrawal A, Rajput R, Fernando R, Sumanatilleke M, Suastika K, Shong YK, Lang B, Bartalena L, and Yang SP
- Subjects
- Humans, Practice Patterns, Physicians', Iodine Radioisotopes therapeutic use, Surveys and Questionnaires, Thyroid Hormones therapeutic use, Antithyroid Agents therapeutic use, Asia, Graves Ophthalmopathy drug therapy, Graves Disease diagnosis, Graves Disease therapy
- Abstract
Aim: Although Graves' disease (GD) is common in endocrine practices worldwide, global differences in diagnosis and management remain. We sought to assess the current practices for GD in countries across Asia and the Pacific (APAC), and to compare these with previously published surveys from North America and Europe., Methods: A web-based survey on GD management was conducted on practicing clinicians. Responses from 542 clinicians were received and subsequently analysed and compared to outcomes from similar surveys from other regions., Results: A total of 542 respondents participated in the survey, 515 (95%) of whom completed all sections. Of these, 86% were medical specialists, 11% surgeons, and 3% nuclear medicine physicians. In addition to serum thyroid-stimulating hormone (TSH) and free thyroxine assays, most respondents would request TSH-receptor autoantibody (TRAb) measurement (68%) during initial work-up. Thyroid ultrasound is requested by about half of respondents (53%), while the use of nuclear medicine scans is limited. The preferred first-line treatment is anti-thyroid drug (ATD) therapy (79%) with methimazole (MMI) or carbimazole (CBZ), followed by radioiodine (RAI; 19%) and surgery (2%). In case of surgery, one-third of respondents would opt for a subtotal rather than a total thyroidectomy. In case of mild Graves orbitopathy (GO), ATDs (67%) remains the preferred treatment, but a larger proportion of clinicians prefer surgery (20%). For a patient with intention to conceive, the preferred treatment pattern remained unchanged, although propylthiouracil (PTU) became the preferred ATD-agent during the first trimester. In comparison to European and American practices, marked differences were noted in the relatively infrequent usage of nuclear medicine scans and the overall higher use of a ATDs and β-blockers and adjunctive ATD-treatment during RAI in the APAC-group., Conclusion: Although regional differences regarding the diagnosis and management of GD are apparent in this first pan-Asia-Pacific survey, this study reveals the overall approach to the management of this disease in Asia-Pacific generally tends to fall between the trends appreciated in the American and European cohorts., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2023
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30. Filamentous nuclear actin regulation of PML NBs during the DNA damage response is deregulated by prelamin A.
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Cobb AM, De Silva SA, Hayward R, Sek K, Ulferts S, Grosse R, and Shanahan CM
- Subjects
- Promyelocytic Leukemia Nuclear Bodies, Cell Nucleus, DNA Damage, DNA, Promyelocytic Leukemia Protein genetics, Actins genetics, Nuclear Proteins genetics
- Abstract
Nuclear actin participates in a continuously expanding list of core processes within eukaryotic nuclei, including the maintenance of genomic integrity. In response to DNA damage, nuclear actin polymerises into filaments that are involved in the repair of damaged DNA through incompletely defined mechanisms. We present data to show that the formation of nuclear F-actin in response to genotoxic stress acts as a scaffold for PML NBs and that these filamentous networks are essential for PML NB fission and recruitment of microbodies to DNA lesions. Further to this, we demonstrate that the accumulation of the toxic lamin A precursor prelamin A induces mislocalisation of nuclear actin to the nuclear envelope and prevents the establishment of nucleoplasmic F-actin networks in response to stress. Consequently, PML NB dynamics and recruitment to DNA lesions is ablated, resulting in impaired DNA damage repair. Inhibition of nuclear export of formin mDia2 restores nuclear F-actin formation by augmenting polymerisation of nuclear actin in response to stress and rescues PML NB localisation to sites of DNA repair, leading to reduced levels of DNA damage., (© 2022. The Author(s).)
- Published
- 2022
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31. PTP1B Is an Intracellular Checkpoint that Limits T-cell and CAR T-cell Antitumor Immunity.
- Author
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Wiede F, Lu KH, Du X, Zeissig MN, Xu R, Goh PK, Xirouchaki CE, Hogarth SJ, Greatorex S, Sek K, Daly RJ, Beavis PA, Darcy PK, Tonks NK, and Tiganis T
- Subjects
- Animals, CD8-Positive T-Lymphocytes metabolism, Cell Line, Tumor, Humans, Immunotherapy, Adoptive, Mice, Protein Tyrosine Phosphatase, Non-Receptor Type 1, Xenograft Model Antitumor Assays, Neoplasms metabolism, Programmed Cell Death 1 Receptor metabolism
- Abstract
Immunotherapies aimed at alleviating the inhibitory constraints on T cells have revolutionized cancer management. To date, these have focused on the blockade of cell-surface checkpoints such as PD-1. Herein we identify protein tyrosine phosphatase 1B (PTP1B) as an intracellular checkpoint that is upregulated in T cells in tumors. We show that increased PTP1B limits T-cell expansion and cytotoxicity to contribute to tumor growth. T cell-specific PTP1B deletion increased STAT5 signaling, and this enhanced the antigen-induced expansion and cytotoxicity of CD8+ T cells to suppress tumor growth. The pharmacologic inhibition of PTP1B recapitulated the T cell-mediated repression of tumor growth and enhanced the response to PD-1 blockade. Furthermore, the deletion or inhibition of PTP1B enhanced the efficacy of adoptively transferred chimeric antigen receptor (CAR) T cells against solid tumors. Our findings identify PTP1B as an intracellular checkpoint whose inhibition can alleviate the inhibitory constraints on T cells and CAR T cells to combat cancer., Significance: Tumors subvert antitumor immunity by engaging checkpoints that promote T-cell exhaustion. Here we identify PTP1B as an intracellular checkpoint and therapeutic target. We show that PTP1B is upregulated in intratumoral T cells and that its deletion or inhibition enhances T-cell antitumor activity and increases CAR T-cell effectiveness against solid tumors. This article is highlighted in the In This Issue feature, p. 587., (©2021 The Authors; Published by the American Association for Cancer Research.)
- Published
- 2022
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32. Adoptive transfer of tumor-specific Th9 cells eradicates heterogeneous antigen-expressing tumor cells.
- Author
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Sek K, Chan CW, Beavis PA, and Darcy PK
- Subjects
- Adoptive Transfer, Humans, Neoplasms genetics, Neoplasms therapy
- Abstract
In this issue of Cancer Cell, Xue et al. demonstrate that adoptive transfer of tumor-specific Th9 cells can eradicate established tumors containing antigen-loss-variant cells (ALVs) through both direct killing and bystander effects mediated by intratumoral accumulation of extracellular ATP (eATP) that promotes monocyte infiltration and stimulation of IFNα/β production., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
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33. MAIT cells regulate NK cell-mediated tumor immunity.
- Author
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Petley EV, Koay HF, Henderson MA, Sek K, Todd KL, Keam SP, Lai J, House IG, Li J, Zethoven M, Chen AXY, Oliver AJ, Michie J, Freeman AJ, Giuffrida L, Chan JD, Pizzolla A, Mak JYW, McCulloch TR, Souza-Fonseca-Guimaraes F, Kearney CJ, Millen R, Ramsay RG, Huntington ND, McCluskey J, Oliaro J, Fairlie DP, Neeson PJ, Godfrey DI, Beavis PA, and Darcy PK
- Subjects
- Animals, Antineoplastic Agents, Cell Line, Tumor, Cytokines, Histocompatibility Antigens Class I genetics, Humans, Immunity, Mice, Mice, Inbred C57BL, Mice, Knockout, Minor Histocompatibility Antigens genetics, Neoplasm Metastasis, Neoplasms pathology, Immunity, Cellular, Killer Cells, Natural immunology, Mucosal-Associated Invariant T Cells immunology, Neoplasms immunology
- Abstract
The function of MR1-restricted mucosal-associated invariant T (MAIT) cells in tumor immunity is unclear. Here we show that MAIT cell-deficient mice have enhanced NK cell-dependent control of metastatic B16F10 tumor growth relative to control mice. Analyses of this interplay in human tumor samples reveal that high expression of a MAIT cell gene signature negatively impacts the prognostic significance of NK cells. Paradoxically, pre-pulsing tumors with MAIT cell antigens, or activating MAIT cells in vivo, enhances anti-tumor immunity in B16F10 and E0771 mouse tumor models, including in the context of established metastasis. These effects are associated with enhanced NK cell responses and increased expression of both IFN-γ-dependent and inflammatory genes in NK cells. Importantly, activated human MAIT cells also promote the function of NK cells isolated from patient tumor samples. Our results thus describe an activation-dependent, MAIT cell-mediated regulation of NK cells, and suggest a potential therapeutic avenue for cancer treatment., (© 2021. Crown.)
- Published
- 2021
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34. CRISPR/Cas9 mediated deletion of the adenosine A2A receptor enhances CAR T cell efficacy.
- Author
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Giuffrida L, Sek K, Henderson MA, Lai J, Chen AXY, Meyran D, Todd KL, Petley EV, Mardiana S, Mølck C, Stewart GD, Solomon BJ, Parish IA, Neeson PJ, Harrison SJ, Kats LM, House IG, Darcy PK, and Beavis PA
- Subjects
- Adenosine metabolism, Adenosine A2 Receptor Antagonists pharmacology, Animals, CRISPR-Cas Systems genetics, Cell Engineering methods, Cell Line, Tumor transplantation, Disease Models, Animal, Female, Gene Editing, Gene Expression Regulation, Neoplastic immunology, Gene Knockdown Techniques, Gene Knockout Techniques, Humans, Lymphocytes, Tumor-Infiltrating immunology, Mice, Mice, Transgenic, Neoplasms genetics, Neoplasms immunology, RNA, Small Interfering metabolism, RNA-Seq, Receptor, Adenosine A2A metabolism, Receptor, ErbB-2 genetics, Receptors, Chimeric Antigen immunology, Receptors, Chimeric Antigen metabolism, Signal Transduction drug effects, Signal Transduction genetics, Signal Transduction immunology, T-Lymphocytes immunology, T-Lymphocytes metabolism, Tumor Escape drug effects, Tumor Escape genetics, Immunotherapy, Adoptive methods, Neoplasms therapy, Receptor, Adenosine A2A genetics, T-Lymphocytes transplantation
- Abstract
Adenosine is an immunosuppressive factor that limits anti-tumor immunity through the suppression of multiple immune subsets including T cells via activation of the adenosine A
2A receptor (A2A R). Using both murine and human chimeric antigen receptor (CAR) T cells, here we show that targeting A2A R with a clinically relevant CRISPR/Cas9 strategy significantly enhances their in vivo efficacy, leading to improved survival of mice. Effects evoked by CRISPR/Cas9 mediated gene deletion of A2A R are superior to shRNA mediated knockdown or pharmacological blockade of A2A R. Mechanistically, human A2A R-edited CAR T cells are significantly resistant to adenosine-mediated transcriptional changes, resulting in enhanced production of cytokines including IFNγ and TNF, and increased expression of JAK-STAT signaling pathway associated genes. A2A R deficient CAR T cells are well tolerated and do not induce overt pathologies in mice, supporting the use of CRISPR/Cas9 to target A2A R for the improvement of CAR T cell function in the clinic.- Published
- 2021
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35. IL-15 Preconditioning Augments CAR T Cell Responses to Checkpoint Blockade for Improved Treatment of Solid Tumors.
- Author
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Giuffrida L, Sek K, Henderson MA, House IG, Lai J, Chen AXY, Todd KL, Petley EV, Mardiana S, Todorovski I, Gruber E, Kelly MJ, Solomon BJ, Vervoort SJ, Johnstone RW, Parish IA, Neeson PJ, Kats LM, Darcy PK, and Beavis PA
- Subjects
- Biomarkers, Tumor, Combined Modality Therapy, Gene Expression Regulation, Neoplastic drug effects, Humans, Immune Checkpoint Proteins metabolism, Lymphocytes, Tumor-Infiltrating drug effects, Lymphocytes, Tumor-Infiltrating immunology, Lymphocytes, Tumor-Infiltrating metabolism, Neoplasms etiology, Treatment Outcome, Immune Checkpoint Inhibitors therapeutic use, Immunotherapy, Adoptive methods, Interleukin-15 administration & dosage, Neoplasms therapy
- Abstract
Chimeric antigen receptor (CAR) T cell therapy has been highly successful in hematological malignancies leading to their US Food and Drug Administration (FDA) approval. However, the efficacy of CAR T cells in solid tumors is limited by tumor-induced immunosuppression, leading to the development of combination approaches, such as adjuvant programmed cell death 1 (PD-1) blockade. Current FDA-approved methods for generating CAR T cells utilize either anti-CD3 and interleukin (IL)-2 or anti-CD3/CD28 beads, which can generate a T cell product with an effector/exhausted phenotype. Whereas different cytokine preconditioning milieu, such as IL-7/IL-15, have been shown to promote T cell engraftment, the impact of this approach on CAR T cell responses to adjuvant immune-checkpoint blockade has not been assessed. In the current study, we reveal that the preconditioning of CAR T cells with IL-7/IL-15 increased CAR T cell responses to anti-PD-1 adjuvant therapy. This was associated with the emergence of an intratumoral CD8
+ CD62L+ TCF7+ IRF4- population that was highly responsive to anti-PD-1 therapy and mediated the vast majority of transcriptional and epigenetic changes in vivo following PD-1 blockade. Our data indicate that preservation of CAR T cells in a TCF7+ phenotype is crucial for their responsiveness to adjuvant immunotherapy approaches and should be a key consideration when designing clinical protocols., (Copyright © 2020 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)- Published
- 2020
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36. Adoptive cellular therapy with T cells expressing the dendritic cell growth factor Flt3L drives epitope spreading and antitumor immunity.
- Author
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Lai J, Mardiana S, House IG, Sek K, Henderson MA, Giuffrida L, Chen AXY, Todd KL, Petley EV, Chan JD, Carrington EM, Lew AM, Solomon BJ, Trapani JA, Kedzierska K, Evrard M, Vervoort SJ, Waithman J, Darcy PK, and Beavis PA
- Subjects
- Animals, Antigens, Neoplasm immunology, Humans, Immunologic Factors, Lymphocyte Activation immunology, Mice, Mice, Inbred C57BL, Mice, Transgenic, Receptors, Antigen, T-Cell immunology, Receptors, Chimeric Antigen immunology, Dendritic Cells immunology, Immunotherapy, Adoptive, Membrane Proteins immunology, Neoplasms, Experimental immunology, T-Lymphocytes immunology
- Abstract
Adoptive cell therapies using genetically engineered T cell receptor or chimeric antigen receptor T cells are emerging forms of immunotherapy that redirect T cells to specifically target cancer. However, tumor antigen heterogeneity remains a key challenge limiting their efficacy against solid cancers. Here, we engineered T cells to secrete the dendritic cell (DC) growth factor Fms-like tyrosine kinase 3 ligand (Flt3L). Flt3L-secreting T cells expanded intratumoral conventional type 1 DCs and substantially increased host DC and T cell activation when combined with immune agonists poly (I:C) and anti-4-1BB. Importantly, combination therapy led to enhanced inhibition of tumor growth and the induction of epitope spreading towards antigens beyond those recognized by adoptively transferred T cells in solid tumor models of T cell receptor and chimeric antigen receptor T cell therapy. Our data suggest that augmenting endogenous DCs is a promising strategy to overcome the clinical problem of antigen-negative tumor escape following adoptive cell therapy.
- Published
- 2020
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37. Pharmacological and genetic strategies for targeting adenosine to enhance adoptive T cell therapy of cancer.
- Author
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Sek K, Kats LM, Darcy PK, and Beavis PA
- Subjects
- Animals, Humans, Neoplasms genetics, Neoplasms immunology, T-Lymphocytes immunology, Tumor Microenvironment immunology, Adenosine immunology, Gene Editing, Immunotherapy, Adoptive, Neoplasms therapy, Receptors, Chimeric Antigen
- Abstract
Adoptive cellular therapy involves the ex vivo expansion of immune cells, conventionally T cells, before reinfusion back to the patient. Variations in adoptive cellular therapy include transduction of a patient's T cells with either a transgenic T cell receptor or chimeric antigen receptor (CAR) to recognize a defined tumor antigen. Given that adenosine is a major axis of immunosuppression of T cells, particularly in hypoxic tumor microenvironments, therapeutics targeting this pathway are currently being assessed for their potential to enhance adoptive T cell therapies. The use of gene-editing technology, commonly used in tandem with CAR and transgenic T cell receptor (TCR) based adoptive cellular therapy, offers further opportunities to specifically modulate responses to adenosine. This review will discuss recent advances in targeting the adenosine pathway for enhancing the effectiveness of adoptive cellular therapy in the treatment of solid cancers., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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38. PET/CT of breast cancer regional nodal recurrences: an evaluation of contouring atlases.
- Author
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Beaton L, Nica L, Tyldesley S, Sek K, Ayre G, Aparicio M, Gondara L, Speers C, and Nichol A
- Subjects
- Adult, Aged, Aged, 80 and over, Breast Neoplasms pathology, Female, Humans, Lymphatic Metastasis pathology, Middle Aged, Neoplasm Recurrence, Local pathology, Positron Emission Tomography Computed Tomography methods, Breast Neoplasms diagnostic imaging, Image Interpretation, Computer-Assisted methods, Lymphatic Metastasis diagnostic imaging, Neoplasm Recurrence, Local diagnostic imaging
- Abstract
Background: To validate the Radiation Therapy Oncology Group (RTOG) and European Society for Radiotherapy and Oncology (ESTRO) breast cancer nodal clinical target volumes (CTVs) and to investigate the Radiotherapy Comparative Effectiveness Consortium (RADCOMP) Posterior Neck volume in relation to regional nodal recurrences (RNR)., Methods: From a population-based database, 69 patients were identified who developed RNR after curative treatment for breast cancer. RNRs were detected with 18-fluorodeoxyglucose-positron emission tomography-computed tomography (PET/CT). All patients were treatment-naïve for RNR when imaged. The RTOG and ESTRO nodal CTVs and RADCOMP Posterior Neck volumes were contoured onto a template patient's CT. RNRs were contoured on each PET/CT and deformed onto the template patient's CT. Each RNR was represented by a 5 mm diameter epicentre, and categorized as 'inside', 'marginal' or 'outside' the CTV boundaries., Results: Sixty-nine patients with 226 nodes (median 2, range 1-11) were eligible for inclusion. Thirty patients had received adjuvant tangent and regional nodal radiotherapy, 16 tangent-only radiotherapy and 23 no adjuvant radiotherapy. For the RTOG CTVs, the RNR epicentres were 70% (158/226) inside, 4% (8/226) marginal and 27% (60/226) outside. They included the full extent of the RNR epicentres in 38% (26/69) of patients. Addition of the RADCOMP Posterior Neck volume increased complete RNR coverage to 48% (33/69) of patients. For the ESTRO CTVs, the RNR epicentres were 73% (165/226) inside, 2% (4/226) marginal and 25% (57/226) outside. They included the full extent of the RNR epicentres in 57% (39/69) of patients. Addition of the RADCOMP Posterior Neck volume increased complete RNR coverage to 70% (48/69) of patients., Conclusions: The RTOG and ESTRO breast cancer nodal CTVs do not fully cover all potential areas of RNR, but the ESTRO nodal CTVs provided full coverage of all RNR epicentres in 19% more patients than the RTOG nodal CTVs. With addition of the RADCOMP Posterior Neck volume to the ESTRO CTVs, 70% of patients had full coverage of all RNR epicentres.
- Published
- 2020
- Full Text
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39. Baseline and Post-treatment 18F-Fluorocholine PET/CT Predicts Outcomes in Hepatocellular Carcinoma Following Locoregional Therapy.
- Author
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Wallace MC, Sek K, Francis RJ, Samuelson S, Ferguson J, Tibballs J, Asad A, Preen DB, MacQuillan G, Garas G, Adams LA, and Jeffrey GP
- Subjects
- Ablation Techniques, Aged, Aged, 80 and over, Brachytherapy, Carcinoma, Hepatocellular etiology, Carcinoma, Hepatocellular pathology, Carcinoma, Hepatocellular therapy, Chemoembolization, Therapeutic, Female, Hepatitis C, Chronic complications, Humans, Liver Cirrhosis, Alcoholic complications, Liver Neoplasms etiology, Liver Neoplasms pathology, Liver Neoplasms therapy, Male, Middle Aged, Neoplasm Staging, Neoplasms, Multiple Primary etiology, Neoplasms, Multiple Primary pathology, Neoplasms, Multiple Primary therapy, Non-alcoholic Fatty Liver Disease complications, Prognosis, Progression-Free Survival, Radiosurgery, Tumor Burden, Carcinoma, Hepatocellular diagnostic imaging, Choline analogs & derivatives, Liver Neoplasms diagnostic imaging, Neoplasms, Multiple Primary diagnostic imaging, Positron Emission Tomography Computed Tomography, Radiopharmaceuticals
- Abstract
Background and Aims:
18 F-fluorocholine positron emission tomography/computed tomography (18 F-FCH PET/CT) is an emerging functional imaging technique in the diagnosis and management of hepatocellular carcinoma (HCC). The aim of this study was to assess the ability of a pre- and post-treatment18 F-FCH PET/CT to predict prognosis and treatment response in early-stage HCC., Methods: Patients with early- or intermediate-stage HCC planned for locoregional therapy were prospectively enrolled. Baseline demographic and tumor information was collected and baseline and post-treatment18 F-FCH PET/CT performed. Maximum standardized uptake values (SUVmax) were determined for each HCC lesion, and the difference between baseline and post-treatment SUVmax values were compared with progression-free survival outcomes., Results: A total of 29 patients with 39 confirmed HCC lesions were enrolled from a single clinical center. Patients were mostly men (89.7%) with hepatitis C or alcohol-related cirrhosis (65.5%) and early-stage disease (89.7%). Per-patient and per-lesion sensitivity of18 F-FCH PET/CT was 72.4% and 59.0%, respectively. A baseline SUVmax < 13 was associated with a superior median progression-free survival compared with an SUVmax of > 13 (17.7 vs. 5.1 months; p = 0.006). A > 45% decrease in SUVmax between baseline and post-treatment18 F-FCH PET/CT ("responders") was associated with a superior mean progression-free survival than a percentage decrease of < 45% ("non-responders," 36.1 vs. 11.6 months; p = 0.034)., Conclusions: Baseline and post-treatment18 F-FCH PET/CT predicts outcomes in early-stage HCC undergoing locoregional therapy. This technique may identify patients with an objective response post-locoregional therapy who would benefit from further therapy.- Published
- 2020
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40. Macrophage-Derived CXCL9 and CXCL10 Are Required for Antitumor Immune Responses Following Immune Checkpoint Blockade.
- Author
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House IG, Savas P, Lai J, Chen AXY, Oliver AJ, Teo ZL, Todd KL, Henderson MA, Giuffrida L, Petley EV, Sek K, Mardiana S, Gide TN, Quek C, Scolyer RA, Long GV, Wilmott JS, Loi S, Darcy PK, and Beavis PA
- Subjects
- Animals, CD8-Positive T-Lymphocytes drug effects, CD8-Positive T-Lymphocytes immunology, Cell Line, Tumor, Macrophages drug effects, Macrophages metabolism, Mice, Mice, Inbred C57BL, Neoplasms drug therapy, Neoplasms metabolism, Neoplasms pathology, Receptors, CXCR3 metabolism, Tumor Microenvironment, CTLA-4 Antigen antagonists & inhibitors, Chemokine CXCL10 metabolism, Chemokine CXCL9 metabolism, Immunotherapy methods, Macrophages immunology, Neoplasms immunology, Programmed Cell Death 1 Receptor antagonists & inhibitors
- Abstract
Purpose: Response rates to immune checkpoint blockade (ICB; anti-PD-1/anti-CTLA-4) correlate with the extent of tumor immune infiltrate, but the mechanisms underlying the recruitment of T cells following therapy are poorly characterized. A greater understanding of these processes may see the development of therapeutic interventions that enhance T-cell recruitment and, consequently, improved patient outcomes. We therefore investigated the chemokines essential for immune cell recruitment and subsequent therapeutic efficacy of these immunotherapies., Experimental Design: The chemokines upregulated by dual PD-1/CTLA-4 blockade were assessed using NanoString-based analysis with results confirmed at the protein level by flow cytometry and cytometric bead array. Blocking/neutralizing antibodies confirmed the requirement for key chemokines/cytokines and immune effector cells. Results were confirmed in patients treated with immune checkpoint inhibitors using single-cell RNA-sequencing (RNA-seq) and paired survival analyses., Results: The CXCR3 ligands, CXCL9 and CXCL10, were significantly upregulated following dual PD-1/CTLA-4 blockade and both CD8
+ T-cell infiltration and therapeutic efficacy were CXCR3 dependent. In both murine models and patients undergoing immunotherapy, macrophages were the predominant source of CXCL9 and their depletion abrogated CD8+ T-cell infiltration and the therapeutic efficacy of dual ICB. Single-cell RNA-seq analysis of patient tumor-infiltrating lymphocytes (TIL) revealed that CXCL9/10/11 was predominantly expressed by macrophages following ICB and we identified a distinct macrophage signature that was associated with positive responses to ICB., Conclusions: These data underline the fundamental importance of macrophage-derived CXCR3 ligands for the therapeutic efficacy of ICB and highlight the potential of manipulating this axis to enhance patient responses., (©2019 American Association for Cancer Research.)- Published
- 2020
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41. Targeting Adenosine Receptor Signaling in Cancer Immunotherapy.
- Author
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Sek K, Mølck C, Stewart GD, Kats L, Darcy PK, and Beavis PA
- Subjects
- Animals, Humans, T-Lymphocytes immunology, Tumor Microenvironment, Immunotherapy, Neoplasms immunology, Neoplasms therapy, Receptors, Purinergic P1 metabolism, Signal Transduction
- Abstract
The immune system plays a major role in the surveillance and control of malignant cells, with the presence of tumor infiltrating lymphocytes (TILs) correlating with better patient prognosis in multiple tumor types. The development of 'checkpoint blockade' and adoptive cellular therapy has revolutionized the landscape of cancer treatment and highlights the potential of utilizing the patient's own immune system to eradicate cancer. One mechanism of tumor-mediated immunosuppression that has gained attention as a potential therapeutic target is the purinergic signaling axis, whereby the production of the purine nucleoside adenosine in the tumor microenvironment can potently suppress T and NK cell function. The production of extracellular adenosine is mediated by the cell surface ectoenzymes CD73, CD39, and CD38 and therapeutic agents have been developed to target these as well as the downstream adenosine receptors (A₁R, A
2A R, A2B R, A₃R) to enhance anti-tumor immune responses. This review will discuss the role of adenosine and adenosine receptor signaling in tumor and immune cells with a focus on their cell-specific function and their potential as targets in cancer immunotherapy.- Published
- 2018
- Full Text
- View/download PDF
42. Dual PD-1 and CTLA-4 Checkpoint Blockade Promotes Antitumor Immune Responses through CD4 + Foxp3 - Cell-Mediated Modulation of CD103 + Dendritic Cells.
- Author
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Beavis PA, Henderson MA, Giuffrida L, Davenport AJ, Petley EV, House IG, Lai J, Sek K, Milenkovski N, John LB, Mardiana S, Slaney CY, Trapani JA, Loi S, Kershaw MH, Haynes NM, and Darcy PK
- Subjects
- Animals, Antigens, CD genetics, CD8-Positive T-Lymphocytes immunology, CTLA-4 Antigen immunology, Cell Line, Tumor, Hepatocyte Nuclear Factor 3-gamma genetics, Immunotherapy, Integrin alpha Chains genetics, Interleukin-12 immunology, Mice, Mice, Inbred C57BL, Programmed Cell Death 1 Receptor immunology, CD4-Positive T-Lymphocytes immunology, CTLA-4 Antigen antagonists & inhibitors, Dendritic Cells immunology, Programmed Cell Death 1 Receptor antagonists & inhibitors
- Abstract
Immunotherapy is widely accepted as a powerful new treatment modality for the treatment of cancer. The most successful form of immunotherapy to date has been the blockade of the immune checkpoints PD-1 and CTLA-4. Combining inhibitors of both PD-1 and CTLA-4 increases the proportion of patients who respond to immunotherapy. However, most patients still do not respond to checkpoint inhibitors, and prognostic biomarkers are currently lacking. Therefore, a better understanding of the mechanism by which these checkpoint inhibitors enhance antitumor immune responses is required to more accurately predict which patients are likely to respond and further enhance this treatment modality. Our current study of two mouse tumor models revealed that CD4
+ Foxp3- cells activated by dual PD-1/CTLA-4 blockade modulated the myeloid compartment, including activation of conventional CD103+ dendritic cells (DC) and expansion of a myeloid subset that produces TNFα and iNOS (TIP-DCs). CD4+ Foxp3- T cell-mediated activation of CD103+ DCs resulted in enhanced IL12 production by these cells and IL12 enhanced the therapeutic effect of dual PD-1/CTLA-4 blockade. Given the importance of these myeloid subsets in the antitumor immune response, our data point to a previously underappreciated role of CD4+ Foxp3- cells in modulating this arm of the antitumor immune response. Cancer Immunol Res; 6(9); 1069-81. ©2018 AACR ., (©2018 American Association for Cancer Research.)- Published
- 2018
- Full Text
- View/download PDF
43. A Novel Target Antigen for the Treatment of Acute Myeloid Leukemia by CAR T Cells.
- Author
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Beavis PA, Sek K, and Darcy PK
- Subjects
- Humans, Immunotherapy, Adoptive, T-Lymphocytes, Leukemia, Myeloid, Acute, Receptors, Antigen, T-Cell
- Published
- 2017
- Full Text
- View/download PDF
44. Targeting the adenosine 2A receptor enhances chimeric antigen receptor T cell efficacy.
- Author
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Beavis PA, Henderson MA, Giuffrida L, Mills JK, Sek K, Cross RS, Davenport AJ, John LB, Mardiana S, Slaney CY, Johnstone RW, Trapani JA, Stagg J, Loi S, Kats L, Gyorki D, Kershaw MH, and Darcy PK
- Subjects
- Animals, Female, Humans, Mammary Neoplasms, Experimental genetics, Mice, Receptor, Adenosine A2A genetics, Receptor, ErbB-2 genetics, Receptor, ErbB-2 immunology, Receptors, Antigen, T-Cell genetics, Recombinant Fusion Proteins genetics, CD4-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes immunology, Mammary Neoplasms, Experimental immunology, Mammary Neoplasms, Experimental therapy, Receptor, Adenosine A2A immunology, Receptors, Antigen, T-Cell immunology, Recombinant Fusion Proteins immunology
- Abstract
Chimeric antigen receptor (CAR) T cells have been highly successful in treating hematological malignancies, including acute and chronic lymphoblastic leukemia. However, treatment of solid tumors using CAR T cells has been largely unsuccessful to date, partly because of tumor-induced immunosuppressive mechanisms, including adenosine production. Previous studies have shown that adenosine generated by tumor cells potently inhibits endogenous antitumor T cell responses through activation of adenosine 2A receptors (A2ARs). Herein, we have observed that CAR activation resulted in increased A2AR expression and suppression of both murine and human CAR T cells. This was reversible using either A2AR antagonists or genetic targeting of A2AR using shRNA. In 2 syngeneic HER2+ self-antigen tumor models, we found that either genetic or pharmacological targeting of the A2AR profoundly increased CAR T cell efficacy, particularly when combined with PD-1 blockade. Mechanistically, this was associated with increased cytokine production of CD8+ CAR T cells and increased activation of both CD8+ and CD4+ CAR T cells. Given the known clinical relevance of the CD73/adenosine pathway in several solid tumor types, and the initiation of phase I trials for A2AR antagonists in oncology, this approach has high translational potential to enhance CAR T cell efficacy in several cancer types.
- Published
- 2017
- Full Text
- View/download PDF
45. A haemostatic agent delivery system for endoscopic neurosurgical procedures.
- Author
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Waran V, Sek K, Bahuri NF, Narayanan P, and Chandran H
- Subjects
- Drug Delivery Systems methods, Endoscopy methods, Hemostasis, Surgical instrumentation, Hemostasis, Surgical methods, Humans, Neurosurgical Procedures methods, Skull Base surgery, Drug Delivery Systems instrumentation, Endoscopy instrumentation, Hemostatics administration & dosage, Neurosurgical Procedures instrumentation
- Abstract
In endoscopic neurosurgery problems with haemostasis due to poor access exist. We have developed a system which allows the delivery of a variety of haemostatic agents in a more efficacious manner. The system has been used successfully in endoscopic skull base surgery and endoscopic surgery within the parenchyma of the brain using tube systems., (© Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2011
- Full Text
- View/download PDF
46. Test of the relationships between the content of heavy metals in sewage sludge and source of their pollution by chemometric methods.
- Author
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Hanć A, Komorowicz I, Sek K, and Baralkiewicz D
- Subjects
- Cluster Analysis, Environmental Monitoring methods, Poland, Principal Component Analysis methods, Spectrum Analysis, Environmental Monitoring statistics & numerical data, Environmental Pollutants analysis, Metals, Heavy analysis, Sewage chemistry, Waste Disposal, Fluid methods
- Abstract
The content of various metals (Cd, Cr, Cu, Ni, Pb and Zn) in sewage sludge was analysed by ICP-OES technique. The study was performed on 14 samples from the Wielkopolska region and 4 from the neighbouring provinces. The results were used to perform chemometric analysis. Two chemometric methods were used to test the relationships between the content of heavy metals in sewage sludge and the sources of their pollution. The application of cluster analysis displayed important information about the identification of similar locations of sewage sludge sampling stations. This chemometric method showed that all the monitoring locations are grouped into three main clusters. Separated clusters present similarities between locations of the sewage treatment plants, which have the same kind of industrial plants in their catchment area. Principal component analysis enabled interpretation of the complex relationships between determined elements. Application of principal component analysis to the whole data set helped to distinguish only two sewage sludge stations (Ostrow Wlkp. and Poznan-Kozieglowy) that could be interpreted, each in different principal component thereby suggesting that element's concentration differ considerably. The interpretation of relationships between the rest of the stations was possible by performing PCA for the second time, but on the reduced data set (two above-mentioned stations were excluded). It distinguished two groups: (1) Gniezno, Srem, Kalisz, Inowrocław and Sroda Wlkp, and (2) Gostyn, Gniezno and Kalisz, which differ with regard to element's concentration.
- Published
- 2009
- Full Text
- View/download PDF
47. Sensitivity of housekeeping genes in the hypothalamus to mismatch in diets between pre- and postnatal periods in mice.
- Author
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Sellayah D, Sek K, Anthony FW, Hanson MA, and Cagampang FR
- Subjects
- Actins genetics, Animals, Animals, Newborn, Female, Glyceraldehyde-3-Phosphate Dehydrogenases genetics, Male, Mice, Pregnancy, RNA, Messenger metabolism, RNA, Ribosomal, 18S genetics, Sensitivity and Specificity, Sex Factors, Actins metabolism, Gene Expression genetics, Glyceraldehyde-3-Phosphate Dehydrogenases metabolism, Hypothalamus embryology, Hypothalamus growth & development, Hypothalamus metabolism, Malnutrition, RNA, Ribosomal, 18S metabolism
- Abstract
Housekeeping genes are used as internal controls in gene expression studies, but their expression levels vary according to tissue types and experimental treatments. A nutritional mismatch between pre- and postnatal periods, wherein the in utero nutritional environment is suboptimal and post-weaning diet is rich in fat, results in altered hypothalamic expression levels of genes that regulate the offspring's physiology, metabolism and behavior. The present study investigated hypothalamic expression of the housekeeping genes glyceraldehyde-3-phosphate dehydrogenase (GAPDH), beta-actin and 18s ribosomal RNA (18s rRNA) in offspring subjected to this pre- and postnatal dietary mismatch. Pregnant MF1 mice were fed standard chow (C, 18% casein) or protein restricted (PR, 9% casein) diet throughout pregnancy. Weaned offspring were fed to adulthood a high fat (HF, 45% kcal fat) or chow (21% kcal fat) diet to generate the C/HF, C/C, PR/HF and PR/C groups. Hypothalamic and cerebral cortex tissues were collected from these offspring at 16 weeks of age and analyzed for gene transcript levels by quantitative real time PCR. Hypothalamic GAPDH mRNA levels were higher in PR/HF male and female offspring vs. all other groups (p<0.001 in males). Conversely, hypothalamic beta-actin and 18s rRNA levels were similar in all treatment groups and sex. In the cerebral cortex, GAPDH and beta-actin levels were similar in all groups and sex. The result suggests that beta-actin and 18s rRNA are suitable internal controls for gene expression studies in the hypothalamus, while the stability of GAPDH is compromised, under the condition of a nutritional mismatch between pre- and postnatal periods.
- Published
- 2008
- Full Text
- View/download PDF
48. Appetite regulatory mechanisms and food intake in mice are sensitive to mismatch in diets between pregnancy and postnatal periods.
- Author
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Sellayah D, Sek K, Anthony FW, Watkins AJ, Osmond C, Fleming TP, Hanson MA, and Cagampang FR
- Subjects
- Animals, Body Weight physiology, Energy Intake physiology, Female, Gene Expression Regulation physiology, Male, Mice, Neuropeptide Y genetics, Neuropeptide Y metabolism, Pregnancy, Pro-Opiomelanocortin genetics, Pro-Opiomelanocortin metabolism, Receptors, Leptin genetics, Receptors, Leptin metabolism, Sex Factors, Appetite, Diet, Protein-Restricted methods, Eating physiology, Hypothalamus metabolism, Prenatal Nutritional Physiological Phenomena
- Abstract
Human and animal studies suggest that obesity in adulthood may have its origins partly during prenatal development. One of the underlying causes of obesity is the perturbation of hypothalamic mechanisms controlling appetite. We determined mRNA levels of genes that regulate appetite, namely neuropeptide Y (NPY), pro-opiomelanocortin (POMC) and the leptin receptor isoform Ob-Rb, in the hypothalamus of adult mouse offspring from pregnant dams fed a protein-restricted diet, and examined whether mismatched post-weaning high-fat diet altered further expression of these gene transcripts. Pregnant MF1 mice were fed either normal protein (C, 18% casein) or protein-restricted (PR, 9% casein) diet throughout pregnancy. Weaned offspring were fed to adulthood a high-fat (HF; 45% kcal fat) or standard chow (21% kcal fat) diet to generate the C/HF, C/C, PR/HF and PR/C groups. Food intake and body weight were monitored during this period. Hypothalamic tissues were collected at 16 weeks of age for analysis of gene expression by real time RT-PCR. All HF-fed offspring were observed to be heavier vs. C groups regardless of the maternal diet during pregnancy. In the PR/HF males, but not in females, daily energy intake was reduced by 20% vs. the PR/C group (p<0.001). In PR/HF males, hypothalamic mRNA levels were lower vs. the PR/C group for NPY (p<0.001) and Ob-Rb (p<0.05). POMC levels were similar in all groups. In females, mRNA levels for these transcripts were similar in all groups. Our results suggest that adaptive changes during prenatal development in response to maternal dietary manipulation may have long-term sex-specific consequences on the regulation of appetite and metabolism following post-weaning exposure to an energy-rich nutritional environment.
- Published
- 2008
- Full Text
- View/download PDF
49. [Safety of influenza vaccination in asthmatics].
- Author
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Kmiecik T, Sek K, and Górski P
- Subjects
- Adolescent, Adult, Aged, Asthma prevention & control, Cross-Over Studies, Double-Blind Method, Female, Follow-Up Studies, Glucocorticoids administration & dosage, Humans, Influenza Vaccines adverse effects, Injections, Intramuscular, Male, Middle Aged, Surveys and Questionnaires, Treatment Outcome, Vaccination methods, Vaccines, Inactivated adverse effects, Asthma complications, Influenza Vaccines administration & dosage, Influenza, Human complications, Influenza, Human prevention & control, Vaccines, Inactivated administration & dosage
- Abstract
The common cause of exacerbations in asthmatics are viral infections. Influenza infection especially increases the risk of respiratory exacerbations. The ACIP report puts asthma among indications to regular influenza vaccinations. In practice, many physicians doubt in effectiveness and safety of vaccination in patients suffering from allergy. It caused such procedures were not included in asthma guidelines published by other authors. Our study confirmed the safety of influenza split vaccine vaccination in asthmatics. We proved that vaccination had not any influence on asthma control in 14-day period after injection. We showed also high frequency of, mostly local, side effects. These events were generally mild and transient.
- Published
- 2006
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