scholarly journals Evaluation of [64Cu]Cu-NOTA-PEG7-H-Tz for Pretargeted Imaging in LS174T Xenografts—Comparison to [111In]In-DOTA-PEG11-BisPy-Tz

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 544
Author(s):  
Christian B. M. Poulie ◽  
Jesper T. Jørgensen ◽  
Vladimir Shalgunov ◽  
Georgios Kougioumtzoglou ◽  
Troels Elmer Jeppesen ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Physicochemical Properties ◽  
Ex Vivo ◽  
Nuclear Imaging ◽  
Imaging Study ◽  
Imaging Agents ◽  
Blocking Assay ◽  
Tetrazine Ligation

Pretargeted nuclear imaging for the diagnosis of various cancers is an emerging and fast developing field. The tetrazine ligation is currently considered the most promising reaction in this respect. Monoclonal antibodies are often the preferred choice as pretargeting vector due to their outstanding targeting properties. In this work, we evaluated the performance of [64Cu]Cu-NOTA-PEG7-H-Tz using a setup we previously used for [111In]In-DOTA-PEG11-BisPy-Tz, thereby allowing for comparison of the performance of these two promising pretargeting imaging agents. The evaluation included a comparison of the physicochemical properties of the compounds and their performance in an ex vivo blocking assay. Finally, [64Cu]Cu-NOTA-PEG7-H-Tz was evaluated in a pretargeted imaging study and compared to [111In]In-DOTA-PEG11-BisPy-Tz. Despite minor differences, this study indicated that both evaluated tetrazines are equally suited for pretargeted imaging.

scholarly journals Site-Specific Dual-Labeling of a VHH with a Chelator and a Photosensitizer for Nuclear Imaging and Targeted Photodynamic Therapy of EGFR-Positive Tumors

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 428
Author(s):  
Emma Renard ◽  
Estel Collado Camps ◽  
Coline Canovas ◽  
Annemarie Kip ◽  
Martin Gotthardt ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Fluorescence Imaging ◽  
Ex Vivo ◽  
Growth Factor Receptor ◽  
Nuclear Imaging ◽  
A431 Cells ◽  
Site Specific ◽  
Variable Domains ◽  
Diagnostic Probe

Variable domains of heavy chain only antibodies (VHHs) are valuable agents for application in tumor theranostics upon conjugation to both a diagnostic probe and a therapeutic compound. Here, we optimized site-specific conjugation of the chelator DTPA and the photosensitizer IRDye700DX to anti-epidermal growth factor receptor (EGFR) VHH 7D12, for applications in nuclear imaging and photodynamic therapy. 7D12 was site-specifically equipped with bimodal probe DTPA-tetrazine-IRDye700DX using the dichlorotetrazine conjugation platform. Binding, internalization and light-induced toxicity of DTPA-IRDye700DX-7D12 were determined using EGFR-overexpressing A431 cells. Finally, ex vivo biodistribution of DTPA-IRDye700DX-7D12 in A431 tumor-bearing mice was performed, and tumor homing was visualized with SPECT and fluorescence imaging. DTPA-IRDye700DX-7D12 was retrieved with a protein recovery of 43%, and a degree of labeling of 0.56. Spectral properties of the IRDye700DX were retained upon conjugation. 111In-labeled DTPA-IRDye700DX-7D12 bound specifically to A431 cells, and they were effectively killed upon illumination. DTPA-IRDye700DX-7D12 homed to A431 xenografts in vivo, and this could be visualized with both SPECT and fluorescence imaging. In conclusion, the dichlorotetrazine platform offers a feasible method for site-specific dual-labeling of VHH 7D12, retaining binding affinity and therapeutic efficacy. The flexibility of the described approach makes it easy to vary the nature of the probes for other combinations of diagnostic and therapeutic compounds.

scholarly journals Publisher Correction: Washing with alkaline solutions in protein A purification improves physicochemical properties of monoclonal antibodies

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuichi Imura ◽  
Toshiaki Tagawa ◽  
Yuya Miyamoto ◽  
Satoshi Nonoyama ◽  
Hiroshi Sumichika ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Physicochemical Properties ◽  
Protein A ◽  
Alkaline Solutions

scholarly journals Role and Modulation of NK Cells in Multiple Myeloma

Hemato ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 167-181
Author(s):  
Marie Thérèse Rubio ◽  
Adèle Dhuyser ◽  
Stéphanie Nguyen
Keyword(s):  
Multiple Myeloma ◽  
Monoclonal Antibodies ◽  
Nk Cells ◽  
Tumor Cells ◽  
Nk Cell ◽  
Ex Vivo ◽  
Killer Cell ◽  
Proteasome Inhibitors ◽  
Disease Evolution ◽  
Cell Functions

Myeloma tumor cells are particularly dependent on their microenvironment and sensitive to cellular antitumor immune response, including natural killer (NK) cells. These later are essential innate lymphocytes implicated in the control of viral infections and cancers. Their cytotoxic activity is regulated by a balance between activating and inhibitory signals resulting from the complex interaction of surface receptors and their respective ligands. Myeloma disease evolution is associated with a progressive alteration of NK cell number, phenotype and cytotoxic functions. We review here the different therapeutic approaches that could restore or enhance NK cell functions in multiple myeloma. First, conventional treatments (immunomodulatory drugs-IMids and proteasome inhibitors) can enhance NK killing of tumor cells by modulating the expression of NK receptors and their corresponding ligands on NK and myeloma cells, respectively. Because of their ability to kill by antibody-dependent cell cytotoxicity, NK cells are important effectors involved in the efficacy of anti-myeloma monoclonal antibodies targeting the tumor antigens CD38, CS1 or BCMA. These complementary mechanisms support the more recent therapeutic combination of IMids or proteasome inhibitors to monoclonal antibodies. We finally discuss the ongoing development of new NK cell-based immunotherapies, such as ex vivo expanded killer cell immunoglobulin-like receptors (KIR)-mismatched NK cells, chimeric antigen receptors (CAR)-NK cells, check point and KIR inhibitors.

scholarly journals Visualisation of interstitial lung disease by molecular imaging of integrin αvβ3 and somatostatin receptor 2

2018 ◽  
Vol 78 (2) ◽  
pp. 218-227 ◽  
Author(s):  
Janine Schniering ◽  
Martina Benešová ◽  
Matthias Brunner ◽  
Stephanie Haller ◽  
Susan Cohrs ◽  
...  
Keyword(s):  
Interstitial Lung Disease ◽  
Lung Disease ◽  
Single Photon ◽  
Ex Vivo ◽  
Somatostatin Receptor ◽  
Photon Emission ◽  
Nuclear Imaging ◽  
Integrin Αvβ3 ◽  
Biodistribution Studies

ObjectiveTo evaluate integrin αvβ3 (alpha-v-beta-3)-targeted and somatostatin receptor 2 (SSTR2)-targeted nuclear imaging for the visualisation of interstitial lung disease (ILD).MethodsThe pulmonary expression of integrin αvβ3 and SSTR2 was analysed in patients with different forms of ILD as well as in bleomycin (BLM)-treated mice and respective controls using immunohistochemistry. Single photon emission CT/CT (SPECT/CT) was performed on days 3, 7 and 14 after BLM instillation using the integrin αvβ3-targeting 177Lu-DOTA-RGD and the SSTR2-targeting 177Lu-DOTA-NOC radiotracer. The specific pulmonary accumulation of the radiotracers over time was assessed by in vivo and ex vivo SPECT/CT scans and by biodistribution studies.ResultsExpression of integrin αvβ3 and SSTR2 was substantially increased in human ILD regardless of the subtype. Similarly, in lungs of BLM-challenged mice, but not of controls, both imaging targets were stage-specifically overexpressed. While integrin αvβ3 was most abundantly upregulated on day 7, the inflammatory stage of BLM-induced lung fibrosis, SSTR2 expression peaked on day 14, the established fibrotic stage. In agreement with the findings on tissue level, targeted nuclear imaging using SPECT/CT specifically detected both imaging targets ex vivo and in vivo, and thus visualised different stages of experimental ILD.ConclusionOur preclinical proof-of-concept study suggests that specific visualisation of molecular processes in ILD by targeted nuclear imaging is feasible. If transferred into clinics, where imaging is considered an integral part of patients’ management, the additional information derived from specific imaging tools could represent a first step towards precision medicine in ILD.

Metronidazole prodrugs: Synthesis, physicochemical properties, stability, and ex vivo release studies

2011 ◽  
Vol 46 (9) ◽  
pp. 4142-4150 ◽  
Author(s):  
Carla Mura ◽  
Donatella Valenti ◽  
Costantino Floris ◽  
Roberta Sanna ◽  
Maria Antonietta De Luca ◽  
...  
Keyword(s):  
Physicochemical Properties ◽  
Ex Vivo ◽  
Release Studies

Monoclonal antibodies to αVβ3 (7E3 and LM609) inhibit sickle red blood cell–endothelium interactions induced by platelet-activating factor

Blood ◽  
2000 ◽  
Vol 95 (2) ◽  
pp. 368-374 ◽  
Author(s):  
D. K. Kaul ◽  
H. M. Tsai ◽  
X. D. Liu ◽  
M. T. Nakada ◽  
R. L. Nagel ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Ex Vivo ◽  
Platelet Activating Factor ◽  
Peripheral Resistance ◽  
Flow Conditions ◽  
Endothelial Surface ◽  
Recovery Times ◽  
Von Willebrand ◽  
Willebrand Factor

Abnormal interaction of sickle red blood cells (SS RBC) with the vascular endothelium has been implicated as a factor in the initiation of vasoocclusion in sickle cell anemia. Both von Willebrand factor (vWf) and thrombospondin (TSP) play important roles in mediating SS RBC–endothelium interaction and can bind to the endothelium via Vβ3 receptors. We have used monoclonal antibodies (MoAb) directed against Vβ3 and IIbβ3 (GPIIb/IIIa) integrins to dissect the role of these integrins in SS RBC adhesion. The murine MoAb 7E3 inhibits both Vβ3 and IIbβ3 (GPIIb/IIIa), whereas MoAb LM609 selectively inhibits Vβ3, and MoAb 10E5 binds only to IIbβ3. In this study, we have tested the capacity of these MoAbs to block platelet-activating factor (PAF)–induced SS RBC adhesion in the ex vivo mesocecum vasculature of the rat. Infusion of washed SS RBC in preparations treated with PAF (200 pg/mL), with or without a control antibody, resulted in extensive adhesion of these cells in venules, accompanied by frequent postcapillary blockage and increased peripheral resistance units (PRU). PAF also caused increased endothelial surface and interendothelial expression of endothelial vWf. Importantly, pretreatment ofthe vasculature with either MoAb 7E3 F(ab′)2 or LM609, but not 10E5 F(ab′)2, after PAF almost completely inhibited SS RBC adhesion in postcapillary venules, the sites of maximal adhesion and frequent blockage. The inhibition of adhesion with 7E3 or LM609 was accompanied by smaller increases in PRU and shorter pressure-flow recovery times. Thus, blockade of Vβ3 may constitute a potential therapeutic approach to prevent SS RBC–endothelium interactions under flow conditions.

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