Synthesis of 68Ga-Labeled cNGR-Based Glycopeptides and In Vivo Evaluation by PET Imaging

Tumor hypoxia induces angiogenesis, which is required for tumor cell survival. The aminopeptidase N receptor (APN/CD13) is an excellent marker of angiogenesis since it is overexpressed in angiogenic blood vessels and in tumor cells. Asparagine-glycine-arginine (NGR) peptide analogs bind selectively to the APN/CD13 recepto, therefore, they are important vector molecules in the development of a PET radiotracer which is capable of detecting APN-rich tumors. To investigate the effect of glycosylation and pegylation on in-vivo efficacy of an NGR-based radiotracer, two 68Ga-labeled radioglycopeptides were synthesized. A lactosamine derivative was applied to glycosylation of the NGR derivative and PEG4 moiety was used for pegylation. The receptor targeting potential and biodistribution of the radiopeptides were evaluated with in vivo PET imaging studies and ex vivo tissue distribution studies using B16-F10 melanoma tumor-bearing mice. According to these studies, all synthesized radiopeptides were capable of detecting APN expression in B16-F10 melanoma tumor. In addition, lower hepatic uptake, higher tumor-to background (T/M) ratio and prolonged circulation time were observed for the novel [68Ga]-10 radiotracer due to pegylation and glycosylation, resulting in more contrasting PET imaging. These in vivo PET imaging results correlated well with the ex vivo tissue distribution data.

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Mechanism-Specific Pharmacodynamics of a Novel Complex-I Inhibitor Quantified by Imaging Reversal of Consumptive Hypoxia with [18F]FAZA PET In Vivo

Cells ◽

10.3390/cells8121487 ◽

2019 ◽

Vol 8 (12) ◽

pp. 1487 ◽

Cited By ~ 2

Author(s):

Seth T. Gammon ◽

Federica Pisaneschi ◽

Madhavi L. Bandi ◽

Melinda G. Smith ◽

Yuting Sun ◽

...

Keyword(s):

Pet Imaging ◽

Complex I ◽

Ex Vivo ◽

Supply And Demand ◽

Tumor Hypoxia ◽

Vascular Supply ◽

Imaging Method ◽

Melanoma Tumor ◽

Ca Ix

Tumors lack a well-regulated vascular supply of O2 and often fail to balance O2 supply and demand. Net O2 tension within many tumors may not only depend on O2 delivery but also depend strongly on O2 demand. Thus, tumor O2 consumption rates may influence tumor hypoxia up to true anoxia. Recent reports have shown that many human tumors in vivo depend primarily on oxidative phosphorylation (OxPhos), not glycolysis, for energy generation, providing a driver for consumptive hypoxia and an exploitable vulnerability. In this regard, IACS-010759 is a novel high affinity inhibitor of OxPhos targeting mitochondrial complex-I that has recently completed a Phase-I clinical trial in leukemia. However, in solid tumors, the effective translation of OxPhos inhibitors requires methods to monitor pharmacodynamics in vivo. Herein, 18F-fluoroazomycin arabinoside ([18F]FAZA), a 2-nitroimidazole-based hypoxia PET imaging agent, was combined with a rigorous test-retest imaging method for non-invasive quantification of the reversal of consumptive hypoxia in vivo as a mechanism-specific pharmacodynamic (PD) biomarker of target engagement for IACS-010759. Neither cell death nor loss of perfusion could account for the IACS-010759-induced decrease in [18F]FAZA retention. Notably, in an OxPhos-reliant melanoma tumor, a titration curve using [18F]FAZA PET retention in vivo yielded an IC50 for IACS-010759 (1.4 mg/kg) equivalent to analysis ex vivo. Pilot [18F]FAZA PET scans of a patient with grade IV glioblastoma yielded highly reproducible, high-contrast images of hypoxia in vivo as validated by CA-IX and GLUT-1 IHC ex vivo. Thus, [18F]FAZA PET imaging provided direct evidence for the presence of consumptive hypoxia in vivo, the capacity for targeted reversal of consumptive hypoxia through the inhibition of OxPhos, and a highly-coupled mechanism-specific PD biomarker ready for translation.

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Development of [18F]FPy-WL12 as a PD-L1 Specific PET Imaging Peptide

Molecular Imaging ◽

10.1177/1536012119852189 ◽

2019 ◽

Vol 18 ◽

pp. 153601211985218 ◽

Cited By ~ 15

Author(s):

Wojciech G. Lesniak ◽

Ronnie C. Mease ◽

Samit Chatterjee ◽

Dhiraj Kumar ◽

Ala Lisok ◽

...

Keyword(s):

Pet Imaging ◽

Ex Vivo ◽

Whole Body ◽

In Vivo Evaluation ◽

Positron Emission ◽

Comprehensive Picture ◽

Specific Uptake ◽

Ex Vivo Biodistribution

Expression of programmed cell death ligand 1 (PD-L1) within tumors is an important biomarker for guiding immune checkpoint therapies; however, immunohistochemistry-based methods of detection fail to provide a comprehensive picture of PD-L1 levels in an entire patient. To facilitate quantification of PD-L1 in the whole body, we developed a peptide-based, high-affinity PD-L1 imaging agent labeled with [18F]fluoride for positron emission tomography (PET) imaging. The parent peptide, WL12, and the nonradioactive analog of the radiotracer, 19FPy-WL12, inhibit PD-1/PD-L1 interaction at low nanomolar concentrations (half maximal inhibitory concentration [IC50], 26-32 nM). The radiotracer, [18F]FPy-WL12, was prepared by conjugating 2,3,5,6-tetrafluorophenyl 6-[18F]fluoronicotinate ([18F]FPy-TFP) to WL12 and assessed for specificity in vitro in 6 cancer cell lines with varying PD-L1 expression. The uptake of the radiotracer reflected the PD-L1 expression assessed by flow cytometry. Next, we performed the in vivo evaluation of [18F]FPy-WL12 in mice bearing cancer xenografts by PET imaging, ex vivo biodistribution, and blocking studies. In vivo data demonstrated a PD-L1-specific uptake of [18F]FPy-WL12 in tumors that is reduced in mice receiving a blocking dose. The majority of [18F]FPy-WL12 radioactivity was localized in the tumors, liver, and kidneys indicating the need for optimization of the labeling strategy to improve the in vivo pharmacokinetics of the radiotracer.

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Synthesis and characterization of Chitosan-Catechol conjugates: Development and in vitro, in silico and in vivo evaluation of mucoadhesive pellets of lafutidine

Journal of Bioactive and Compatible Polymers ◽

10.1177/0883911521997849 ◽

2021 ◽

pp. 088391152199784

Author(s):

Loveleen Kaur ◽

Ajay Kumar Thakur ◽

Pradeep Kumar ◽

Inderbir Singh

Keyword(s):

Drug Release ◽

In Silico ◽

Ex Vivo ◽

Strong Interactions ◽

Dissolution Time ◽

Sem Images ◽

In Vivo Evaluation ◽

Release Studies

Present study was aimed to synthesize and characterize Chitosan-Catechol conjugates and to design and develop mucoadhesive pellets loaded with lafutidine. SEM images indicated the presence of fibrous structures responsible for enhanced mucoadhesive potential of Chitosan-Catechol conjugates. Thermodynamic stability and amorphous nature of conjugates was confirmed by DSC and XRD studies respectively. Rheological studies were used to evaluate polymer mucin interactions wherein strong interactions between Chitosan-Catechol conjugate and mucin was observed in comparison to pristine chitosan and mucin. The mucoadhesion potential of Chitosan-Catechol (Cht-C) versus Chitosan (Cht) was assessed in silico using molecular mechanics simulations and the results obtained were compared with the in vitro and ex vivo results. Cht-C/mucin demonstrated much higher energy stabilization (∆E ≈ −65 kcal/mol) as compared to Cht/mucin molecular complex. Lafutidine-loaded pellets were prepared from Chitosan (LPC) and Chitosan-Catechol conjugates (LPCC) and were evaluated for various physical properties viz. flow, circularity, roundness, friability, drug content, particle size and percent mucoadhesion. In vitro drug release studies on LPC and LPCC pellets were performed for computing t50%, t90% and mean dissolution time. The values of release exponent from Korsmeyer-Peppas model was reported to be 0.443 and 0.759 for LPC and LPCC pellets suggesting Fickian and non-Fickian mechanism representing drug release, respectively. In vivo results depicted significant controlled release and enhanced residence of the drug after being released from the chitosan-catechol coated pellets. Chitosan-Catechol conjugates were found to be a promising biooadhesive polymer for the development of various mucoadhesive formulations.

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Effect of Processing on Fish Protein Antigenicity and Allergenicity

Foods ◽

10.3390/foods10050969 ◽

2021 ◽

Vol 10 (5) ◽

pp. 969

Author(s):

Xingyi Jiang ◽

Qinchun Rao

Keyword(s):

Fish Species ◽

Protein Denaturation ◽

Ex Vivo ◽

Protein Solubility ◽

Future Research ◽

Food Protein ◽

In Vivo Evaluation ◽

Fish Allergy

Fish allergy is a life-long food allergy whose prevalence is affected by many demographic factors. Currently, there is no cure for fish allergy, which can only be managed by strict avoidance of fish in the diet. According to the WHO/IUIS Allergen Nomenclature Sub-Committee, 12 fish proteins are recognized as allergens. Different processing (thermal and non-thermal) techniques are applied to fish and fishery products to reduce microorganisms, extend shelf life, and alter organoleptic/nutritional properties. In this concise review, the development of a consistent terminology for studying food protein immunogenicity, antigenicity, and allergenicity is proposed. It also summarizes that food processing may lead to a decrease, no change, or even increase in fish antigenicity and allergenicity due to the change of protein solubility, protein denaturation, and the modification of linear or conformational epitopes. Recent studies investigated the effect of processing on fish antigenicity/allergenicity and were mainly conducted on commonly consumed fish species and major fish allergens using in vitro methods. Future research areas such as novel fish species/allergens and ex vivo/in vivo evaluation methods would convey a comprehensive view of the relationship between processing and fish allergy.

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Pivotal role of Acitretin nanovesicular gel for effective treatment of psoriasis: ex vivo–in vivo evaluation study

International Journal of Nanomedicine ◽

10.2147/ijn.s156412 ◽

2018 ◽

Vol Volume 13 ◽

pp. 1059-1079 ◽

Cited By ~ 17

Author(s):

Irhan Abu Hashim ◽

Noha Abo El-Magd ◽

Ahmed El-Sheakh ◽

Mohammed Hamed ◽

Abd El-Gawad Abd El-Gawad

Keyword(s):

Effective Treatment ◽

Ex Vivo ◽

Evaluation Study ◽

Pivotal Role ◽

In Vivo Evaluation

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In Vitro and In Vivo Evaluation of Human Adenovirus Type 49 as a Vector for Therapeutic Applications

Viruses ◽

10.3390/v13081483 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1483

Author(s):

Emily A. Bates ◽

John R. Counsell ◽

Sophie Alizert ◽

Alexander T. Baker ◽

Natalie Suff ◽

...

Keyword(s):

Viral Vector ◽

Ex Vivo ◽

Human Adenovirus ◽

Adenovirus Type ◽

Cell Types ◽

In Vivo Evaluation ◽

In Vivo Biodistribution ◽

Adenovirus Type 5

The human adenovirus phylogenetic tree is split across seven species (A–G). Species D adenoviruses offer potential advantages for gene therapy applications, with low rates of pre-existing immunity detected across screened populations. However, many aspects of the basic virology of species D—such as their cellular tropism, receptor usage, and in vivo biodistribution profile—remain unknown. Here, we have characterized human adenovirus type 49 (HAdV-D49)—a relatively understudied species D member. We report that HAdV-D49 does not appear to use a single pathway to gain cell entry, but appears able to interact with various surface molecules for entry. As such, HAdV-D49 can transduce a broad range of cell types in vitro, with variable engagement of blood coagulation FX. Interestingly, when comparing in vivo biodistribution to adenovirus type 5, HAdV-D49 vectors show reduced liver targeting, whilst maintaining transduction of lung and spleen. Overall, this presents HAdV-D49 as a robust viral vector platform for ex vivo manipulation of human cells, and for in vivo applications where the therapeutic goal is to target the lung or gain access to immune cells in the spleen, whilst avoiding liver interactions, such as intravascular vaccine applications.

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