LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 7 of total 7

Search options

  1. Article ; Online: High-Resolution Epitope Mapping and Affinity Binding Analysis Comparing a New Anti-Human LAG3 Rabbit Antibody Clone to the Commonly Used Mouse 17B4 Clone.

    Warren, P Daniel / Dodson, Mark S / Smith, Margaret H / Landowski, Terry H / Palting, John Douglas / Towne, Penny

    Antibodies (Basel, Switzerland)

    2022  Volume 11, Issue 4

    Abstract: Lymphocyte activation gene 3 (LAG3) is a T cell inhibitory receptor that promotes tumor cell immune escape and is a potential target for cancer diagnostic and immunotherapeutic applications. We used automated capillary electrophoresis (ACE), surface ... ...

    Abstract Lymphocyte activation gene 3 (LAG3) is a T cell inhibitory receptor that promotes tumor cell immune escape and is a potential target for cancer diagnostic and immunotherapeutic applications. We used automated capillary electrophoresis (ACE), surface plasmon resonance (SPR), and immunohistochemistry (IHC) to compare the binding characteristics of a new anti-LAG3 rabbit antibody clone, SP464, with the thirty-year old and extensively used anti-LAG3 mouse 17B4 clone. The rabbit SP464 clone exhibited between 20× to 30× greater binding to LAG3 than did the mouse 17B4 clone. Using these tools, we precisely mapped the relative locations of the epitopes of these two antibodies. The SP464 and 17B4 minimal epitopes were localized to separate, but overlapping, sub-fragments within the amino-terminal fifteen acids of the original thirty-mer peptide immunogen used to generate both antibodies. Application of this approach for quantifying the effects of alanine substitutions along the minimal SP464 epitope identified two amino acids essential for binding and four amino acids that likely contribute towards binding. Together, ACE, SPR, and IHC constitute a powerful orthologous approach for comparing antibody-binding characteristics and for fine mapping of linear epitopes within short immunogens. Our results indicate that the rabbit clone SP464 may be useful for assessing LAG3 expression.
    Language English
    Publishing date 2022-09-21
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2661514-9
    ISSN 2073-4468 ; 2073-4468
    ISSN (online) 2073-4468
    ISSN 2073-4468
    DOI 10.3390/antib11040060
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: Fluorescent multiplexing of 3D spheroids: Analysis of biomarkers using automated immunohistochemistry staining platform and multispectral imaging.

    Bhaumik, Srabani / Boyer, Jean / Banerjee, Chaitali / Clark, Samantha / Sebastiao, Noemi / Vela, Elizabeth / Towne, Penny

    Journal of cellular biochemistry

    2020  Volume 121, Issue 12, Page(s) 4974–4990

    Abstract: In preclinical cancer studies, three-dimensional (3D) cell spheroids and aggregates are preferred over monolayer cell cultures due to their architectural and functional similarity to solid tumors. We performed a proof-of-concept study to generate ... ...

    Abstract In preclinical cancer studies, three-dimensional (3D) cell spheroids and aggregates are preferred over monolayer cell cultures due to their architectural and functional similarity to solid tumors. We performed a proof-of-concept study to generate physiologically relevant and predictive preclinical models using non-small cell lung adenocarcinoma, and colon and colorectal adenocarcinoma cell line-derived 3D spheroids and aggregates. Distinct panels were designed to determine the expression profiles of frequently studied biomarkers of the two cancer subtypes. The lung adenocarcinoma panel included ALK, EGFR, TTF-1, and CK7 biomarkers, and the colon and colorectal adenocarcinoma panel included BRAF V600E, MSH2, MSH6, and CK20. Recent advances in immunofluorescence (IF) multiplexing and imaging technology enable simultaneous detection and quantification of multiple biomarkers on a single slide. In this study, we performed IF staining of multiple biomarkers per section on formalin-fixed paraffin-embedded 3D spheroids and aggregates. We optimized protocol parameters for automated IF and demonstrated staining concordance with automated chromogenic immunohistochemistry performed with validated protocols. Next, post-acquisition spectral unmixing of the captured fluorescent signals were utilized to delineate four differently stained biomarkers within a single multiplex IF image, followed by automated quantification of the expressed markers. This workflow has the potential to be adapted to preclinical high-throughput screening and drug efficacy studies utilizing 3D spheroids from cancer cell lines and patient-derived organoids. The process allows for cost, time, and resource savings through concurrent staining of several biomarkers on a single slide, the ability to study the interactions of multiple expressed proteins within a single region of interest, and enable quantitative assessment of biomarkers in cancer cells.
    Language English
    Publishing date 2020-07-21
    Publishing country United States
    Document type Journal Article
    ZDB-ID 392402-6
    ISSN 1097-4644 ; 0730-2312
    ISSN (online) 1097-4644
    ISSN 0730-2312
    DOI 10.1002/jcb.29827
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: Activity of trastuzumab emtansine (T-DM1) in 3D cell culture.

    Boyer, Jean Zheng / Phillips, Gail D Lewis / Nitta, Hiro / Garsha, Karl / Admire, Brittany / Kraft, Robert / Dennis, Eslie / Vela, Elizabeth / Towne, Penny

    Breast cancer research and treatment

    2021  Volume 188, Issue 1, Page(s) 65–75

    Abstract: Background: Cell spheroids and aggregates generated from three-dimensional (3D) cell culture methods are similar to in vivo tumors in terms of tissue morphology, biology, and gene expression, unlike cells grown in 2D cell cultures. Breast cancer ... ...

    Abstract Background: Cell spheroids and aggregates generated from three-dimensional (3D) cell culture methods are similar to in vivo tumors in terms of tissue morphology, biology, and gene expression, unlike cells grown in 2D cell cultures. Breast cancer heterogeneity is one of the main drug resistant mechanisms and needs to be overcome in order to increase the efficacy of drug activity in its treatments.
    Methods: We performed a unique 3D cell culture and drug efficacy study with trastuzumab emtansine (Kadcyla®, T-DM1) across five breast cancer cell lines (BT-474, SK-BR-3, MDA-MB-361, MDA-MB-175, and MCF-7) that were previously investigated in 2D cell culture. We performed HER2 IHC staining, cell viability experiments, Gene-protein-assay (GPA), and T-DM1 internalization studies.
    Results: We obtained significantly different results including higher IC
    Conclusion: Our study demonstrated that the difference of T-DM1 drug activity in 3D spheroids or aggregates might be due to tumor heterogeneity and less efficient internalization of T-DM1 that is not seen using 2D cell culture models. Drug studies using 3D cell culture are expected to provide biologically relevant models for determining drug activity in tumor tissue in future drug response and resistance research.
    MeSH term(s) Ado-Trastuzumab Emtansine ; Breast Neoplasms ; Cell Culture Techniques ; Cell Line, Tumor ; Female ; Humans ; Maytansine ; Receptor, ErbB-2 ; Trastuzumab
    Chemical Substances Maytansine (14083FR882) ; Receptor, ErbB-2 (EC 2.7.10.1) ; Trastuzumab (P188ANX8CK) ; Ado-Trastuzumab Emtansine (SE2KH7T06F)
    Language English
    Publishing date 2021-06-05
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 604563-7
    ISSN 1573-7217 ; 0167-6806
    ISSN (online) 1573-7217
    ISSN 0167-6806
    DOI 10.1007/s10549-021-06272-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: Impact of Pre-Analytical Conditions on the Antigenicity of Lung Markers: ALK and MET.

    Miller, Rachel / Thorne-Nuzzo, Trish / Loftin, Isabell / McElhinny, Abigail / Towne, Penny / Clements, June

    Applied immunohistochemistry & molecular morphology : AIMM

    2019  Volume 28, Issue 5, Page(s) 331–338

    Abstract: Diagnostic assays for molecular alterations highly correlated with prognosis, predictive efficacy or safety of therapeutics are valuable clinical tools and in some cases approved as companion diagnostics (CDx) by the Federal Food and Drug Administration. ...

    Abstract Diagnostic assays for molecular alterations highly correlated with prognosis, predictive efficacy or safety of therapeutics are valuable clinical tools and in some cases approved as companion diagnostics (CDx) by the Federal Food and Drug Administration. For example, assays that determine echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) translocation status have been approved as CDx assay for therapies that target this molecular alteration. Characterizing the parameters that may compromise diagnostic accuracy for molecular biomarkers is critical for optimal patient care. To investigate the impact of pre-analytical handling and processing of tumor tissue on commonly used diagnostic immunohistochemistry-based assays for ALK and mesenchymal epithelial transition protein [c-mesenchymal epithelial transition (c-MET)], we investigated the effects of cold ischemia, fixative type, fixation time, and cut-slide age on staining consistency and intensity using human lung xenograft tumor tissue. Cold ischemia times for up to 5 to 6 hours for c-MET or ALK, respectively had minimal impact on staining. The optimal fixation conditions for both assays were found to be at least 6 hours and up to 48 hours for c-MET or 72 hours for ALK, in 10% neutral buffered formalin and Zinc formalin. The ALK antigen demonstrated marked staining intensity differences across non-neutral buffered formalin fixative types and times. Finally, cut-slide age influenced assay performance for both ALK and c-MET, with maximum stability observed when cut slides were stored at ambient temperatures (30°C) for no longer than 3, and 5 months, respectively. This study highlights the potential for pre-analytical factors to confound diagnostic test result interpretation.
    MeSH term(s) Anaplastic Lymphoma Kinase/metabolism ; Animals ; Biomarkers, Tumor/metabolism ; Carcinoma, Non-Small-Cell Lung/metabolism ; Carcinoma, Non-Small-Cell Lung/pathology ; Cell Line, Tumor ; Female ; Fixatives/chemistry ; Humans ; Immunohistochemistry ; Lung ; Lung Neoplasms/metabolism ; Lung Neoplasms/pathology ; Mice ; Mice, SCID ; Prognosis ; Proto-Oncogene Proteins c-met/metabolism ; Tissue Fixation/methods ; Xenograft Model Antitumor Assays
    Chemical Substances Biomarkers, Tumor ; Fixatives ; ALK protein, human (EC 2.7.10.1) ; Anaplastic Lymphoma Kinase (EC 2.7.10.1) ; Proto-Oncogene Proteins c-met (EC 2.7.10.1)
    Language English
    Publishing date 2019-02-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1473273-7
    ISSN 1533-4058 ; 1062-3345 ; 1541-2016
    ISSN (online) 1533-4058
    ISSN 1062-3345 ; 1541-2016
    DOI 10.1097/PAI.0000000000000730
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article ; Online: A Sensitive ALK Immunohistochemistry Companion Diagnostic Test Identifies Patients Eligible for Treatment with Crizotinib.

    Thorne-Nuzzo, Trish / Williams, Crystal / Catallini, Alice / Clements, June / Singh, Shalini / Amberson, James / Dickinson, Kim / Gatalica, Zoran / Ho, Steffan N / Loftin, Isabell / McElhinny, Abigail / Towne, Penny

    Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer

    2017  Volume 12, Issue 5, Page(s) 804–813

    Abstract: Introduction: The availability of high-quality, rigorously validated diagnostic tests that can be broadly implemented is necessary to efficiently identify patients with anaplastic lymphoma kinase (ALK)-positive NSCLC who can potentially benefit from ... ...

    Abstract Introduction: The availability of high-quality, rigorously validated diagnostic tests that can be broadly implemented is necessary to efficiently identify patients with anaplastic lymphoma kinase (ALK)-positive NSCLC who can potentially benefit from treatment with crizotinib. Here we present data on the recently approved Ventana ALK (D5F3) CDx Assay (Ventana Medical Systems, Tucson, AZ), the only immunohistochemistry (IHC)-based assay linked to treatment outcome.
    Methods: NSCLC specimens prospectively tested for anaplastic lymphoma receptor tyrosine kinase gene (ALK) status by flourescent in situ hybridization (FISH) in the PROFILE 1014 clinical trial of crizotinib versus chemotherapy (N = 1018, including 179 ALK-positive and 754 ALK-negative specimens) were evaluated using the ALK (D5F3) CDx assay. Hazard ratios for progression-free survival comparing crizotinib and chemotherapy for ALK IHC-positive patients and ALK FISH-positive patients, as well as for concordance with the enrollment ALK FISH assay, were determined.
    Results: Results from both assays were obtained for 933 cases. Percent positive, negative, and overall agreement rates were 86.0% , 96.3%, and 94.3%, respectively. There were 53 discrepant cases, of which 25 were ALK FISH-positive/ALK IHC-negative and 28 were ALK FISH-negative/ALK IHC-positive. The hazard ratios using observed outcomes were 0.401 for ALK FISH-positive/ALK IHC-positive cases and 0.407 for all ALK FISH-positive cases tested with ALK IHC versus 0.454 for all ALK FISH-positive cases enrolled in the trial. Outcome data for ALK FISH-negative/ALK IHC-positive cases were not available for analysis. Between-reader agreement rates for ALK IHC involving three independent laboratories exceeded 98%.
    Conclusions: The ALK (D5F3) CDx assay is a stand-alone companion diagnostic test for identification of patients for treatment with crizotinib. This automated assay provides an effective option to accurately and rapidly identify patients with ALK-positive NSCLC. The simple binary scoring algorithm results in high reader-to-reader precision.
    Language English
    Publishing date 2017-05
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2432037-7
    ISSN 1556-1380 ; 1556-0864
    ISSN (online) 1556-1380
    ISSN 1556-0864
    DOI 10.1016/j.jtho.2017.01.020
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article ; Online: PD-L1 Immunohistochemistry Assays for Lung Cancer: Results from Phase 1 of the Blueprint PD-L1 IHC Assay Comparison Project.

    Hirsch, Fred R / McElhinny, Abigail / Stanforth, Dave / Ranger-Moore, James / Jansson, Malinka / Kulangara, Karina / Richardson, William / Towne, Penny / Hanks, Debra / Vennapusa, Bharathi / Mistry, Amita / Kalamegham, Rasika / Averbuch, Steve / Novotny, James / Rubin, Eric / Emancipator, Kenneth / McCaffery, Ian / Williams, J Andrew / Walker, Jill /
    Longshore, John / Tsao, Ming Sound / Kerr, Keith M

    Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer

    2017  Volume 12, Issue 2, Page(s) 208–222

    Abstract: Introduction: The Blueprint Programmed Death Ligand 1 (PD-L1) Immunohistochemistry (IHC) Assay Comparison Project is an industrial-academic collaborative partnership to provide information on the analytical and clinical comparability of four PD-L1 IHC ... ...

    Abstract Introduction: The Blueprint Programmed Death Ligand 1 (PD-L1) Immunohistochemistry (IHC) Assay Comparison Project is an industrial-academic collaborative partnership to provide information on the analytical and clinical comparability of four PD-L1 IHC assays used in clinical trials.
    Methods: A total of 39 NSCLC tumors were stained with four PD-L1 IHC assays (22C3, 28-8, SP142, and SP263), as used in the clinical trials. Three experts in interpreting their respective assays independently evaluated the percentages of tumor and immune cells staining positive at any intensity. Clinical diagnostic performance was assessed through comparisons of patient classification above and below a selected expression cutoff and by agreement using various combinations of assays and cutoffs.
    Results: Analytical comparison demonstrated that the percentage of PD-L1-stained tumor cells was comparable when the 22C3, 28-8, and SP263 assays were used, whereas the SP142 assay exhibited fewer stained tumor cells overall. The variability of immune cell staining across the four assays appears to be higher than for tumor cell staining. Of the 38 cases, 19 (50.0%) were classified above and five (13%) were classified below the selected cutoffs of all assays. For 14 of the 38 cases (37%), a different PD-L1 classification would be made depending on which assay/scoring system was used.
    Conclusions: The Blueprint PD-L1 IHC Assay Comparison Project revealed that three of the four assays were closely aligned on tumor cell staining whereas the fourth showed consistently fewer tumor cells stained. All of the assays demonstrated immune cell staining, but with greater variability than with tumor cell staining. By comparing assays and cutoffs, the study indicated that despite similar analytical performance of PD-L1 expression for three assays, interchanging assays and cutoffs would lead to "misclassification" of PD-L1 status for some patients. More data are required to inform on the use of alternative staining assays upon which to read different specific therapy-related PD-L1 cutoffs.
    Language English
    Publishing date 2017-02
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2432037-7
    ISSN 1556-1380 ; 1556-0864
    ISSN (online) 1556-1380
    ISSN 1556-0864
    DOI 10.1016/j.jtho.2016.11.2228
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article ; Online: New methods for ALK status diagnosis in non-small-cell lung cancer: an improved ALK immunohistochemical assay and a new, Brightfield, dual ALK IHC-in situ hybridization assay.

    Nitta, Hiroaki / Tsuta, Koji / Yoshida, Akihiko / Ho, Steffan N / Kelly, Brian D / Murata, Lauren B / Kosmeder, Jerry / White, Katie / Ehser, Sandra / Towne, Penny / Schemp, Crystal / McElhinny, Abigail / Ranger-Moore, Jim / Bieniarz, Chris / Singh, Shalini / Tsuda, Hitoshi / Grogan, Thomas M

    Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer

    2013  Volume 8, Issue 8, Page(s) 1019–1031

    Abstract: Introduction: The demonstration of anaplastic lymphoma kinase (ALK) positivity in non-small-cell lung cancer (NSCLC) has been hindered by the technical complexity and interpretative challenges of fluorescence in situ hybridization methods for detection ... ...

    Abstract Introduction: The demonstration of anaplastic lymphoma kinase (ALK) positivity in non-small-cell lung cancer (NSCLC) has been hindered by the technical complexity and interpretative challenges of fluorescence in situ hybridization methods for detection of ALK gene rearrangement and by the inadequate sensitivity of existing immunohistochemistry (IHC) methods for ALK protein detection. In this study, we sought to increase the sensitivity of ALK IHC detection and to develop a brightfield assay for concurrent detection of ALK protein expression and ALK gene rearrangement.
    Methods: We developed a horseradish peroxidase-based IHC detection system using the novel, nonendogenous hapten 3-hydroxy-2-quinoxaline (HQ) and tyramide. We also developed a dual gene protein ALK assay combining a brightfield break-apart in situ hybridization ALK assay with another sensitive IHC method using the novel, nonendogenous hapten 5-nitro-3-pyrazole. We examined the sensitivity and accuracy of these methods using surgically resected NSCLC cases examined with ALK fluorescence in situ hybridization.
    Results: The new HQ-tyramide IHC detection system offered readily interpretable staining with substantially greater sensitivity than conventional ALK IHC, and produced heterogeneous and homogeneous patterns of ALK protein staining among ALK-positive NSCLC surgical cases. The new 5-nitro-3-pyrazole-based IHC detection system was similar in ALK detection sensitivity to the HQ-tyramide IHC system and was compatible with the brightfield in situ hybridization assay.
    Conclusion: The new HQ-tyramide IHC reagent system allows more sensitive assessment of ALK protein status in NSCLC cases. The new ALK gene-protein assay allows the concurrent visualization of ALK gene and ALK protein status in single cells, allowing more accurate ALK status determination even in heterogeneous specimens.
    MeSH term(s) Carcinoma, Non-Small-Cell Lung/chemistry ; Cell Line, Tumor ; Haptens/immunology ; Humans ; Immunohistochemistry/methods ; In Situ Hybridization, Fluorescence/methods ; Lung Neoplasms/chemistry ; Receptor Protein-Tyrosine Kinases/analysis
    Chemical Substances Haptens ; Receptor Protein-Tyrosine Kinases (EC 2.7.10.1) ; anaplastic lymphoma kinase (EC 2.7.10.1)
    Language English
    Publishing date 2013-08
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2432037-7
    ISSN 1556-1380 ; 1556-0864
    ISSN (online) 1556-1380
    ISSN 1556-0864
    DOI 10.1097/JTO.0b013e31829ebb4d
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top