cancer-research

Ha K, Bidlingmaier S, Su Y, Lee N, Liu B (2017) Identification of novel macropinocytosing human antibodies by phage display and high-content analysis. Methods Enzymol 585:91-110. doi: 10.1016/bs.mie.2016.10.004

Objective: To describe a method for identifying antibodies that internalize via macropinocytosis by screening phage-displayed single-chain antibody selection outputs with an automated fluorescent microscopy-based high-content analysis platform.

Summary: Novel phage antibodies are identified by colocalization with macropinocytosis marker, converted into full-length human antibodies, and further characterized with regard to cell binding, pathway of internalization, and intracellular payload delivery.

Usage: Biotinylated IgG is mixed with Streptavidin-ZAP in 1:1 molar ratio to form an immunotoxin that is serially-diluted in a cytotoxicity assay.

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

Nohara S, Kato K, Fujiwara D, Sakuragi N, Yanagihara K, Iwanuma Y, Kajiyama Y (2016) Aminopeptidase N (APN/CD13) as a target molecule for scirrhous gastric cancer. Clin Res Hepatol Gastroenterol 40:494-503. doi: 10.1016/j.clinre.2015.11.003

Summary: Scirrhous gastric cancer has the worst prognosis of gastric carcinoma, and treatment with standard cancer therapies has had minimal success. In this work the authors target CD13 as a marker for scirrhous gastric cancer. A gastric cancer cell line was challenged with a CD13 antibody coupled to Mab-ZAP (Cat. #IT-04) in an in vitro cytotoxicity assay. The anti-CD13 complex was more cytotoxic than an anti-EpCAM-immmunotoxin. These data, combined with flow cytometry analysis and enzyme activity assays, demonstrate the expression of CD13 as a marker for scirrhous gastric cancer.

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

Hay C, Sult E, Huang Q, Mulgrew K, Fuhrmann S, McGlinchey K, Hammond S, Rothstein R, Rios-Doria J, Poon E, Holoweckyj N, Durham N, Leow C, Diedrich G, Damschroder M, Herbst R, Hollingsworth R, Sachsenmeier K (2016) Targeting CD73 in the tumor microenvironment with MEDI9447. Oncoimmunology 5:e1208875. doi: 10.1080/2162402X.2016.1208875

Summary: MEDI9447 is a human monoclonal antibody that is specific for the ectoenzyme CD73 and currently undergoing Phase I clinical trials. Here the authors show that MEDI9447 is a potent inhibitor of CD73 ectonucleotidase activity, with wide ranging immune regulatory consequences. MEDI9447 results in relief from adenosine monophosphate (AMP)-mediated lymphocyte suppression in vitro and inhibition of mouse syngeneic tumor growth in vivo. In contrast with other cancer immunotherapy agents such as checkpoint inhibitors or T-cell agonists, MEDI9447 drives changes in both myeloid and lymphoid infiltrating leukocyte populations within the tumor microenvironment of mouse models. In vitro experiments validating the internalization of antibodies into cell lines MDA-MB-231 and 4T1 were measured using the Fab-ZAP human antibody internalization kit (Cat. #KIT-51-Z). Combination data showing additive activity between MEDI9447 and anti-PD-1 antibodies using human cells in vitro and mouse tumor models further demonstrate the potential value of relieving adenosine-mediated immunosuppression. Based on these data, a Phase I study to test the safety, tolerability, and clinical activity of MEDI9447 in cancer patients was initiated (NCT02503774).

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

Palchaudhuri R, Saez B, Hoggatt J, Schajnovitz A, Sykes D, Tate T, Czechowicz A, Kfoury Y, Ruchika F, Rossi D, Verdine G, Mansour M, Scadden D (2016) Non-genotoxic conditioning for hematopoietic stem cell transplantation using a hematopoietic-cell-specific internalizing immunotoxin. Nat Biotechnol 34:738-745. doi: 10.1038/nbt.3584

Summary: To demonstrate correction of a clinically relevant disease, we employed CD45-SAP in a mouse model of sickle cell anemia and demonstrated our method achieved >90% donor cell chimerism, all mice in three groups (18/18), resulting in complete disease correction (red blood cell counts, hemoglobin levels, hematocrit levels and reticulocyte frequencies were returned to normal). If these pre-clinical results can be successfully translated to the clinic, it would greatly reduce conditioning-related toxicities and expand the use of hematopoietic stem cell transplantation.

Related Products: Streptavidin-ZAP (Cat. #IT-27), Anti-CD45.2-SAP (Cat. #IT-91)

Read the featured article in Targeting Trends.

Palchaudhuri R (2016) Featured Article: Targeted depletion of hematopoietic stem cells promises safer transplantation. Targeting Trends 17(3)

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

Read the featured article in Targeting Trends.

See Also:

• Palchaudhuri R et al. Non-genotoxic conditioning for hematopoietic stem cell transplantation using a hematopoietic-cell-specific internalizing immunotoxin. Nat Biotechnol 34:738-745, 2016.
• Skulimowska I et al. The biology of hematopoietic stem cells and its clinical implications. FEBS J 16192, 2021.

Polito L, Djemil A, Bortolotti M (2016) Plant toxin-based immunotoxins for cancer therapy: a short overview. Biomedicines 4(2):12. doi: 10.3390/biomedicines4020012

Related Products: Saporin (Cat. #PR-01)

Dickey D, Thomas G, Dassie J, Giangrande P (2016) Method for confirming cytoplaintratumoral anti-HuD immunotoxinsmic delivery of RNA aptamers. (eds. Shum K, Rossi J). In: SiRNA Delivery Methods. Methods in Molecular Biology. 1364:209-217. Humana Press, New York, NY. doi: 10.1007/978-1-4939-3112-5_17

Objective: To describe a functional assay (RIP assay) to confirm cellular uptake and subsequent cytoplasmic release of an RNA aptamer which binds to a cell surface receptor expressed on prostate cancer cells (PSMA).

Summary: This publication details an in vitro functional assay to confirm that the aptamer retains function following conjugation to saporin and describe a cellular assay to measure aptamer-mediated saporin-induced cytotoxicity.

Usage: The folded biotinylated aptamer was mixed at a 1:4 molar ratio of Streptavidin-ZAP, confirmed by agarose gel, a PSMA enzymatic activity (NAALADase) assay performed. FGF-SAP was used as a control.

Related Products: Streptavidin-ZAP (Cat. #IT-27), FGF-SAP (Cat. #IT-38)

Sedlik C, Heitzmann A, Viel S, Ait Sarkouh R, Batisse C, Schmidt F, De La Rochere P, Amzallag N, Osinaga E, Oppezzo P, Pritsch O, Sastre-Garau X, Hubert P, Amigorena S, Piaggio E (2016) Effective antitumor therapy based on a novel antibody-drug conjugate targeting the Tn carbohydrate antigen. Oncoimmunology 5:e1171434. doi: 10.1080/2162402X.2016.1171434

Summary: Scientists wanted to study the potential of Chi-Tn, a monoclonal antibody against a glycol-peptidic tumor-associated antigen, as an anticancer antibody-drug conjugate. They demonstrated that Chi-Tn specifically targeted tumor cells in vivo, using flow cytometry and deconvolution microscopy to show that Chi-Tn is rapidly internalized. Chi-Tn-SAP (ATS Custom Services) effectively killed Tn-positive cells, but had no effect on Tn-negative cells. Saporin (Cat. #PR-01) was used as control. The cytotoxicity of the Chi-Tn-SAP correlated with the level of tumoral Tn expression.

Related Products: Saporin (Cat. #PR-01), Custom Conjugates

Yuan X, Yang M, Chen X, Zhang X, Sukhadia S, Musolino N, Bao H, Chen T, Xu C, Wang Q, Santoro S, Ricklin D, Hu J, Lin R, Yang W, Li Z, Qin W, Zhao A (2017) 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.. doi: 10.1007/s00262-016-1937-z

Summary: Tumor endothelial marker 1 (TEM1) has been identified as a novel surface marker upregulated on the blood vessels and stroma in many solid tumors. The authors previous isolated a single-chain variable fragment (scFv) 78 against TEM1 from a yeast display scFv library and evaluated potential applications of scFv78 as a tool for tumor molecular imaging, immunotoxin-based therapy and nanotherapy. MS1 and MS1-hTEM1 cells were treated with site-specifically biotinylated scFv78 conjugated with the Streptavidin-ZAP (Cat. #IT-27) at a molar ratio of 4:1 (scFv78:ZAP) starting from 40 nM serially diluted down to 0.04 nM. The scFv78-saporin immunoconjugate exerted dose-dependent cytotoxicity with high specificity to TEM1-positive cell in vitro. The data indicate that scFv78, the first fully human anti-TEM1 recombinant antibody, recognizes both human and mouse TEM1 and has features advantageous for the development of imaging probes or antibody-toxin conjugates for a large spectrum of human TEM1-positive solid tumors.

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

Lee SB, Frattini V, Bansal M, Castano AM, Sherman D, Hutchinson K, Bruce JN, Califano A, Liu G, Cardozo T, Iavarone A, Lasorella A (2016) An ID2-dependent mechanism for VHL inactivation in cancer. Nature 529(7585):172-177. doi: 10.1038/nature16475 PMID: 26735018

Usage: Western blot

Related Products: Trans-4-Hydroxy-L-Proline Rabbit Polyclonal, Conjugated (Cat. #AB-T044)