scholarly journals In Vivo Evaluation of Gallium-68-Labeled IRDye800CW as a Necrosis Avid Contrast Agent in Solid Tumors

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Marcus C.M. Stroet ◽  
Erik de Blois ◽  
Joost Haeck ◽  
Yann Seimbille ◽  
Laura Mezzanotte ◽  
...  

Necrosis only occurs in pathological situations and is directly related to disease severity and, therefore, is an important biomarker. Tumor necrosis occurs in most solid tumors due to improperly functioning blood vessels that cannot keep up with the rapid growth, especially in aggressively growing tumors. The amount of necrosis per tumor volume is often correlated to rapid tumor proliferation and can be used as a diagnostic tool. Furthermore, efficient therapy against solid tumors will directly or indirectly lead to necrotic tumor cells, and detection of increased tumor necrosis can be an early marker for therapy efficacy. We propose the application of necrosis avid contrast agents to detect therapy-induced tumor necrosis. Herein, we advance gallium-68-labeled IRDye800CW, a near-infrared fluorescent dye that exhibits excellent necrosis avidity, as a potential PET tracer for in vivo imaging of tumor necrosis. We developed a reliable labeling procedure to prepare [68Ga]Ga-DOTA-PEG4-IRDye800CW ([68Ga]Ga-1) with a radiochemical purity of >96% (radio-HPLC). The prominent dead cell binding of fluorescence and radioactivity from [68Ga]Ga-1 was confirmed with dead and alive cultured 4T1-Luc2 cells. [68Ga]Ga-1 was injected in 4T1-Luc2 tumor-bearing mice, and specific fluorescence and PET signal were observed in the spontaneously developing tumor necrosis. The ip injection of D-luciferin enabled simultaneous bioluminescence imaging of the viable tumor regions. Tumor necrosis binding was confirmed ex vivo by colocalization of fluorescence uptake with TUNEL dead cell staining and radioactivity uptake in dichotomized tumors and frozen tumor sections. Our presented study shows that [68Ga]Ga-1 is a promising PET tracer for the detection of tumor necrosis.

2021 ◽  
Author(s):  
Yohana C. Toner ◽  
Adam A. Ghotbi ◽  
Sonum Naidu ◽  
Ken Sakurai ◽  
Mandy M.T. Leent ◽  
...  

Abstract The somatostatin receptor 2-binding PET tracer DOTATATE is emerging as an alternative to 18F-FDG to assess cardiovascular inflammation. The strengths and weaknesses of each tracer and their different specificity for inflammatory cells still need to be fully elucidated. In this manuscript, we employed mouse and rabbit animal models of inflammation. In mice, 64Cu-DOTATATE’s pharmacokinetics and timed biodistribution were determined in control (C57BL/6) and atherosclerotic (Apoe−/−) mice by ex vivo gamma counting. In vivo PET/CT, combined with ex vivo flow cytometry and gamma counting, was used to evaluate the quantification of cardiovascular inflammation by 64Cu-DOTATATE and 18F-FDG and the tracers’ cellular specificity in control versus infarcted and atherosclerotic mice. In a translational PET/MRI rabbit study, we then compared DOTATATE labeled with short-lived radioisotope 68Ga and 18F-FDG for the assessment of aortic inflammation, combined with ex vivo radiometric assays and near-infrared imaging of macrophage burden. In infarcted mice, in vivo 64Cu-DOTATATE PET showed higher differential uptake than 18F-FDG between infarcted and remote myocardium (p=0.0286), and with respect to controls (p=0.0286; n=4-6). In atherosclerotic mice, 64Cu-DOTATATE PET aortic signal, but not 18F-FDG, was higher compared to controls (p=0.0286; n=4). In both models, 64Cu-DOTATATE demonstrated preferential accumulation in macrophages with respect to other myeloid cells, while 18F-FDG uptake was less cell-specific. The translational rabbit PET/MRI study showed significantly higher aortic accumulation of both 68Ga-DOTATATE and 18F-FDG in atherosclerotic compared to control animals (p=0.0002 and p=0.0159, respectively; n=10-32). In conclusion, we introduce a workflow integrating in vivo PET and ex vivo immunological and radioactivity counting assays to characterize DOTATATE and 18F-FDG as inflammation tracers in small animal models of cardiovascular disease. Our results support the use of DOTATATE to assess cardiovascular inflammation, as alternative and complement to 18F-FDG. In addition, our study establishes a comprehensive and robust framework for the thorough assessment and comparison of novel and validated PET immuno-tracers in the cardiovascular arena.


2021 ◽  
pp. 088391152199784
Author(s):  
Loveleen Kaur ◽  
Ajay Kumar Thakur ◽  
Pradeep Kumar ◽  
Inderbir Singh

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.


Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 969
Author(s):  
Xingyi Jiang ◽  
Qinchun Rao

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.


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 922
Author(s):  
William Querido ◽  
Shital Kandel ◽  
Nancy Pleshko

Advances in vibrational spectroscopy have propelled new insights into the molecular composition and structure of biological tissues. In this review, we discuss common modalities and techniques of vibrational spectroscopy, and present key examples to illustrate how they have been applied to enrich the assessment of connective tissues. In particular, we focus on applications of Fourier transform infrared (FTIR), near infrared (NIR) and Raman spectroscopy to assess cartilage and bone properties. We present strengths and limitations of each approach and discuss how the combination of spectrometers with microscopes (hyperspectral imaging) and fiber optic probes have greatly advanced their biomedical applications. We show how these modalities may be used to evaluate virtually any type of sample (ex vivo, in situ or in vivo) and how “spectral fingerprints” can be interpreted to quantify outcomes related to tissue composition and quality. We highlight the unparalleled advantage of vibrational spectroscopy as a label-free and often nondestructive approach to assess properties of the extracellular matrix (ECM) associated with normal, developing, aging, pathological and treated tissues. We believe this review will assist readers not only in better understanding applications of FTIR, NIR and Raman spectroscopy, but also in implementing these approaches for their own research projects.


2018 ◽  
Vol Volume 13 ◽  
pp. 1059-1079 ◽  
Author(s):  
Irhan Abu Hashim ◽  
Noha Abo El-Magd ◽  
Ahmed El-Sheakh ◽  
Mohammed Hamed ◽  
Abd El-Gawad Abd El-Gawad

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1483
Author(s):  
Emily A. Bates ◽  
John R. Counsell ◽  
Sophie Alizert ◽  
Alexander T. Baker ◽  
Natalie Suff ◽  
...  

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.


Author(s):  
Chuangjia Huang ◽  
Xiaoling Guan ◽  
Hui Lin ◽  
Lu Liang ◽  
Yingling Miao ◽  
...  

Indocyanine green (ICG), a near-infrared (NIR) fluorescent dye approved by the Food and Drug Administration (FDA), has been extensively used as a photoacoustic (PA) probe for PA imaging. However, its practical application is limited by poor photostability in water, rapid body clearance, and non-specificity. Herein, we fabricated a novel biomimetic nanoprobe by coating ICG-loaded mesoporous silica nanoparticles with the cancer cell membrane (namely, CMI) for PA imaging. This probe exhibited good dispersion, large loading efficiency, good biocompatibility, and homologous targeting ability to Hela cells in vitro. Furthermore, the in vivo and ex vivo PA imaging on Hela tumor-bearing nude mice demonstrated that CMI could accumulate in tumor tissue and display a superior PA imaging efficacy compared with free ICG. All these results demonstrated that CMI might be a promising contrast agent for PA imaging of cervical carcinoma.


2019 ◽  
Vol 36 (7) ◽  
pp. 603-621 ◽  
Author(s):  
Aashu Gupta ◽  
Kritika Nayak ◽  
Manju Misra
Keyword(s):  
Ex Vivo ◽  

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