zap-conjugates

Palchaudhuri R, Hyzy SL, Proctor JL, Adams HL, Pearse BR, Sarma G, Aslanian S, Gillard G, Lamothe TL, Burenkova O, Brooks ML, Gabros AD, McDonagh CF, Boitano AE, Cooke MP (2018) Antibody drug conjugates targeted to CD45 or CD117 enable allogeneic hematopoietic stem cell transplantation in animal models. Blood 132:3324. doi: 10.1182/blood-2018-99-119432

Objective: To further investigate and develop the utility of CD45-SAP and CD117-SAP, in combination with immunosuppression, in murine transplant models using i.v. administration in an allogeneic minor mismatch transplant model (Balb/c donor into DBA/2 recipients).

Summary: CD45-SAP or CD117-SAP in combination with immunosuppressants (30Fll and post-transplant Cytoxan) enabled >85% peripheral donor chimerism at 12 weeks post-transplantation. CD45-SAP and CD117-SAP were more effective at conditioning versus 2Gy TBI or pretransplant Cytoxan.

Usage: CD45-SAP (1.9 mg/kg, iv) and CD117-SAP (1mg/kg, iv) in an allogeneic minor mismatch transplant model (Balb/c donor into DBA/2 recipients).

Related Products: Streptavidin-ZAP (Cat. #IT-27)

Ancheta L, Bouajram R, Lappi DA (2018) Screening targeting agents and their cell surface biomarkers for high specificity and rapid internalization via cell death and fluorescence. Neuroscience 2018 Abstracts 128.20 / M17. Society for Neuroscience, San Diego, CA.

Summary: Some of the most recent successes in the treatment of cancers or research into passive immunotherapies for neurodegenerative diseases, employ the use of antibodies. These treatments utilize antibodies that either: 1) interfere with cell surface proteins responsible for tumor cell proliferation, 2) act as immune checkpoint inhibitors, or 3) are re-engineered to allow transport of other molecules across the blood-brain barrier (BBB). There are a growing number of antibody and small molecule therapeutic candidates and this demands a quick and efficient technique to screen for biomarkers that internalize effectively upon binding. The method described provides for the efficient determination of internalization of cell surface biomarkers upon binding of antibodies or peptides. This one-step, robust method uses a targeting agent combined with both a fluorescent reporter and a cytotoxic payload. The construct that makes this method effective was formed by cross-linking a fluorescent reporter, in this case fluorescein (FITC) and streptavidin to the ribosome-inactivating protein, Saporin. The conjugate used in screening potential therapeutics is a mixture of a biotinylated targeting agent mixed in a 1:1 molar ratio with FITC-labeled Streptavidinylated-Saporin. The method provides a definitive assay readout: fluorescence within 1 hour and cell death in 72 hours. This method is designed for rapid screening, in a quick and reproducible manner, for specificity and internalization in various cell types to explore suitability of candidates as therapeutics.

Related Products: Streptavidin-ZAP (Cat. #IT-27), FITC-Streptavidin-ZAP (Cat. #IT-85)

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See Also:

• Tan HL et al. Conservation of oncofetal antigens on human embryonic stem cells enables discovery of monoclonal antibodies against cancer. Sci Rep 8:11608, 2018.
• Yuan X et al. Characterization of the first fully macropinocytosing human antibodies human anti-TEM1 scFv in models of solid tumor imaging and immunotoxin-based therapy. Cancer Immunol Immunother 66:367-378, 2017.
• Forsyth PA et al. p75 neurotrophin receptor cleavage by α- and γ-secretases is required for neurotrophin-mediated proliferation of brain tumor-initiating cells. J Biol Chem 289(12):8067-8085, 2014.
• Thakkar JP et al. Epidemiologic and molecular prognostic review of glioblastoma. Cancer Epidemiol Biomarkers Prev 23(10):1985-1996, 2014.
• Kohls M Evaluate Potential Targeting Molecules. Nature Methods , 2006.

Su Y, Liu Y, Behrens CR, Bidlingmaier S, Lee NK, Aggarwal R, Sherbenou DW, Burlingame AL, Hann BC, Simko JP, Premasekharan G, Paris PL, Shuman MA, Seo Y, Small EJ, Liu B (2018) Targeting CD46 for both adenocarcinoma and neuroendocrine prostate cancer. JCI Insight 3(17):e121497. doi: 10.1172/jci.insight.121497 PMID: 30185663

Objective: To investigate the suitability of a CD46 antibody as a metastatic castration-resistant prostate cancer (mCRPC) anti-tumor agent.

Summary: CD46 is an excellent candidate for antibody-based therapy development, which has potential to be applicable to both adenocarcinoma and neuroendocrine types of mCRPC that are resistant to current treatment.

Usage: Biotinylated UA20 IgG and Streptavidin-ZAP were mixed at a molar ratio of 1:1. The conjugate was used in cytotoxicity assays and shown to specifically kill the mCRPC cells.

Related Products: Streptavidin-ZAP (Cat. #IT-27)

Tan HL, Yong C, Tan BZ, Fong WJ, Padmanabhan J, Chin A, Ding V, Lau A, Zheng L, Bi X, Yang Y, Choo A (2018) Conservation of oncofetal antigens on human embryonic stem cells enables discovery of monoclonal antibodies against cancer. Sci Rep 8:11608. doi: 10.1038/s41598-018-30070-z

Objective: To identify and characterize an antibody raised using human embryonic stem cells with potential as a cancer therapeutic.

Summary: Antibody A19 not only binds to undifferentiated hESCs by flow cytometry, it also reacts with ovarian and breast cancer cell lines with low or no binding to normal cells.

Usage: in vitro – Number of viable cells treated showed a decrease in cell number (Hum-ZAP mixed with A19; Streptavidin-ZAP mixed with biotinylated A19). To determine if there were off-target effects, Hum-ZAP and chA19 were incubated with a non-binding cell line OVCAR10; no apparent cytotoxicity was observed. invivo – 5 x 106 SKOV3 cells were implanted s.c. in NUDE mice and Biotinylated A19-Streptavidin-ZAP (ADC), administered ip. The controls were free Saporin and naked A19. By the end of 10 weeks, mice administered with the ADC saw a 60% reduction in tumor size compared to control groups.

Related Products: Hum-ZAP (Cat. #IT-22), Streptavidin-ZAP (Cat. #IT-27), Saporin (Cat. #PR-01)

Hoffmann RM, Crescioli S, Thurston DE, Karagiannis SN (2018) Development and evaluation of T-Zap: a novel antibody-drug conjugate for the treatment of Her2 positive breast cancer. Cancer Res 78:LB-001. doi: 10.1158/1538-7445.AM2018-LB-001 PMID: 909090

Objective: Develop and Evaluate a novel ADC (T-Zap) for breast cancer.

Summary: Binding to target cells of T-Zap was confirmed. Comparison of T-Zap efficacy in breast cancer cell lines with and without resistance against trastuzumab showed a trend for higher efficacy of cell killing by T-Zap in trastuzumab resistant cells compared to T-DM1. Toxicity assays revealed no impact of T-Zap on cell viability in immune cells.

Usage: T-ZAP was made using Biotinylated monoclonal antibody trastuzumab mixed with Streptavidin-ZAP.

Related Products: Streptavidin-ZAP (Cat. #IT-27)

Harvey BP, Cohen-Solal J, Kaymakcalan Z (2018) SAT0058 Adalimumab: TNF complexes are cleared more efficiently by human osteoclasts than those with etanercept through FCG-receptor binding and internalisation. Ann Rheum Dis 77:893. EULAR 2018, Amsterdam, The Netherlands doi: 10.1136/annrheumdis-2018-eular.3804

Objective: To determine whether Fc-gamma receptor (FcgR)-mediated internalization of the biologic:TNF complexes is a contributing mechanism responsible for the difference in effectiveness between ADA and ETN in preventing TNF- enhanced OCgenesis.

Summary: Human osteoclast  (OC) precursors can bind and internalise ADA:TNF complexes more efficiently than ETN:TNF complexes. In addition, this process is partially mediated through FcgRII.

Usage: FcgR-mediated nternalization was assessed by monitoring a reduction in OC survival in response to preformed bio- logic: TNF complexes (25:1 ratio) bound with FabFC-ZAP human ± FcgR blocking antibodies.

Related Products: FabFc-ZAP human (Cat. #IT-65)

Sakamoto A, Kato K, Hasegawa T, Ikeda S (2018) An agonistic antibody to EPHA2 exhibits antitumor effects on human melanoma cells. Anticancer Res 38:3273-3282. doi: 10.21873/anticanres.12592

Objective: Investigate the therapeutic potential of antibody to EPHA2 against melanoma in vitro.

Summary: Observations indicate a promising role for EPHA2 as a target in antibody treatments for melanoma, and demonstrate the potential therapeutic effects of an agonistic antibody to EPHA2.

Usage: A375 cells were plated into a flat-bottom, 96-well plate (2,000 cells per well) and incubated for 4 days at 37˚C. Cell suspension included different concentrations of Mab-ZAP, along with either anti-EPHA2 mAb (SHM16, SHM17, or SHM20 at 2 μg/ml final concentration), or a control IgG1 mAb (2 μg/ml final concentration).

Related Products: Mab-ZAP (Cat. #IT-04)

Sadhukhan R, Brown N, Ouellette D, Banach D, Filoti DI, Winarta D, Raghavendra R, Sousa S, Darcy A, Alessandri L, Ivanov A, Bose S, Eaton L, Preston G, Freeman J, Correia I (2018) Engineering elastic properties into an anti-TNFα monoclonal antibody. Cogent Biol 4(1):1469387. doi: 10.1080/23312025.2018.1469387

Objective: To engineer elastic properties into a TNFalpha antibody.

Summary: The results presented in this report with an anti-TNFα ELP mAb are a foundation for building on a new generation of fusion ELP mAbs, or other formats, that are stable, active, responsive to cues in local environment, and, with the FcRn mutation, cleared rapidly from circulation. More detailed studies are warranted to identify the appropriate ELP sequences for IA delivery, calculate residence time in the IA space, and demonstrate pharmacodynamics effect of the ELP-fusion protein.

Usage: Fab-ZAP human was mixed with anti-TNFα-ELP fusion monoclonal.

Related Products: Fab-ZAP human (Cat. #IT-51)

Wüstemann T, Haberkorn U, Babich J, Mier W (2019) Targeting prostate cancer: Prostate-specific membrane antigen based diagnosis and therapy. Med Res Rev 39(1):40-69. doi: 10.1002/med.21508 PMID: 29771460

Summary: Conjugation to the antibody was achieved by reacting the biotinylated humanized antibody to prostate-specific membrane antigen (PMSA) with Streptavidin-ZAP. Binding potency of the conjugate was comparable to that of the naked antibody and in vivo experiments proved potent for selective tumor growth inhibition in mice bearing LNCaP tumors.

Related Products: Streptavidin-ZAP (Cat. #IT-27)

See Also:

• Kuroda K et al. Saporin toxin-conjugated monoclonal antibody targeting prostate-specific membrane antigen has potent anticancer activity. Prostate 70(12):1286-1294, 2010.

Eng MS, Kaur J, Prasmickaite L, Engesaeter BO, Weyergang A, Skarpen E, Berg K, Rosenblum MG, Maelandsmo GM, Hogset A, Ferrone S, Selbo PK (2018) Enhanced targeting of triple-negative breast carcinoma and malignant melanoma by photochemical internalization of CSPG4-targeting immunotoxins. Photochem Photobiol Sci 17:539-551. doi: 10.1039/C7PP00358G

Summary: The combination of the drug delivery technology PCI and CSPG4-targeting immunotoxins is an efficient, specific and light-controlled strategy for the elimination of aggressive cells of TNBC and malignant melanoma origin. This study lays the foundation for further preclinical evaluation of PCI in combination with CSPG4-targeting.

Usage: To obtain the immunotoxin 225.28-saporin, Streptavidin-Saporin (Cat. #IT-27; Streptavidin-ZAP), with an average of 2.5 molecules of saporin per molecule of streptavidin, was combined with biotinylated 225.28, a CSPG4-specific mouse mAb, IgG2a.

Related Products: Streptavidin-ZAP (Cat. #IT-27)