Human carbonic anhydrase IX is a membrane enzyme that is significantly expressed in some types of cancer cells, while copper radioisotopes offer wide range of diagnostic, therapeutic and theranostic properties. The work was focused on a new approach to the labelling of antibody IgG M75 for epitope human carbonic anhydrase IX with copper radioisotopes 61Cu and 64Cu and its in vivo testing in mice with inoculated colorectal cancer. Monoclonal antibody IgG M75 for epitope human carbonic anhydrase IX was successfully conjugated with copper-specific chelator "phosphinate" and labelled with 61Cu and 64Cu The obtained molecule has considerable potential as a radioimmuno pharmaceutical suitable for imaging of tumours expressing carbonic anhydrase IX by positron emission tomography (PET).
- MeSH
- antigeny nádorové imunologie MeSH
- buňky HT-29 MeSH
- imunoglobulin G chemie MeSH
- imunokonjugáty chemie farmakokinetika MeSH
- karboanhydrasa IX imunologie MeSH
- kolorektální nádory diagnostické zobrazování enzymologie MeSH
- lidé MeSH
- monoklonální protilátky chemie farmakokinetika MeSH
- myši nahé MeSH
- myši MeSH
- pozitronová emisní tomografie MeSH
- radiofarmaka chemie farmakokinetika MeSH
- radioimunodetekce MeSH
- radioizotopy mědi chemie farmakokinetika MeSH
- tkáňová distribuce MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Specific oncology diagnostics requires new types of the selective radiopharmaceuticals, particularly those suitable for the molecular PET imaging. The aim of this work is to present a new, specific PET-immunodiagnostic radiopharmaceutical based on the monoclonal antibody IgG M75 targeting human carbonic anhydrase IX labelled with 64Cu (T½ = 12.70h) and its in vitro and in vivo evaluation. The antibody IgG M75 was conjugated with a non-commercial copper-specific chelator "phosphinate" and then labelled with the positron emitter 64Cu. Stability of the labelled conjugated was tested in human serum. The immunoreactivity of the labelled conjugate was evaluated in vitro on a suitable cell cultures of the colorectal carcinoma (HT-29) and its imaging properties were estimated in vivo on a mouse model with inoculated colorectal carcinoma HT-29 imaged on a µPET/CT. The tested radioimmunoconjugate was obtained in a specific activity of 0.25-0.5 MBq/µg. In vitro uptake experiments revealed specific binding to the HT-29 cells (45 ± 2.8% of the total added activity) and the measured KD value was found to be 9.2nM. Imaging clearly demonstrated significant uptake of the labelled monoclonal antibody in the tumour at 18h post administration. The radioimmunoconjugate 64Cu-PS-IgG M75 seems to be a suitable candidate for PET diagnostics of hypoxic tumours expressing human carbonic anhydrase IX.
- MeSH
- aktivní transport MeSH
- antigeny nádorové imunologie MeSH
- buňky HT-29 MeSH
- buňky NIH 3T3 MeSH
- imunokonjugáty farmakokinetika farmakologie MeSH
- inhibitory enzymů farmakokinetika farmakologie MeSH
- karboanhydrasa IX antagonisté a inhibitory imunologie MeSH
- kyseliny fosfinové MeSH
- lidé MeSH
- monoklonální protilátky farmakokinetika farmakologie MeSH
- myši nahé MeSH
- myši MeSH
- nádory diagnostické zobrazování enzymologie MeSH
- PET/CT MeSH
- protinádorové látky imunologicky aktivní farmakokinetika farmakologie MeSH
- radiofarmaka farmakokinetika farmakologie MeSH
- radioizotopy mědi farmakokinetika farmakologie MeSH
- techniky in vitro MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- Publikační typ
- abstrakt z konference MeSH
- Publikační typ
- abstrakt z konference MeSH
- Publikační typ
- abstrakt z konference MeSH
- Publikační typ
- abstrakt z konference MeSH
- Publikační typ
- abstrakt z konference MeSH
BACKGROUND: Cholecystokinin receptor subtype 2 (CCK-2) is overexpressed in various tumours like medullary thyroid carcinomas and small cell lung cancer. Radiolabelled peptides that bind with high affinity and specificity to CCK-2 receptors, thus hold great potential for visualizing such tumours. METHODS: We compared four 111In labelled gastrin analogues, called minigastrins (MG), namely MG11, MG45, MG47 and MG48 linked to metal chelating DOTA in preclinical experiments. The radiolabelled peptides were tested for peptide binding in CCK-2 receptor-bearing cell line AR42J and for their pharmacokinetics in normal rats. RESULTS: The experiments suggest that all gastrin analogues had similar and relatively rapid internalization into AR42J cells. Binding to CCK-2 receptors in AR42J cells was saturable for all agents but there were some differences in receptor affinity. This biodistribution study in rats showed a rapid decrease in blood radioactivity, predominantly renal clearance and saturable uptake of the radiopharmaceutical and/or its metabolites in the CCK-2 receptor-positive stomach. Higher kidney accumulation of radioactivity was only found for 111In-DOTA-minigastrin 48. CONCLUSIONS: The data suggest that the 111In-DOTA-minigastrin analogues studied are promising candidates for the scintigraphy of CCK-2 receptor-expressing tumours; 111In-DOTA-MG47 and 111In-DOTA-MG11 are the most promising.
- MeSH
- gastriny farmakokinetika farmakologie MeSH
- heterocyklické sloučeniny monocyklické MeSH
- komplexní sloučeniny MeSH
- krysa rodu rattus MeSH
- nádorové buněčné linie MeSH
- peptidy MeSH
- radiofarmaka MeSH
- receptor cholecystokininu B metabolismus MeSH
- tkáňová distribuce MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A nanofibrous membrane carrier for nearly water insoluble drug diosmin was formulated. The aim of this study was to evaluate the drug release and dissolution properties in an aqueous buffer of pH 7.8, and to compare the suitability of the drug carrier with the available drug forms and screen diosmin absorption extent. The membranes were produced from HPC/PVA/PEO-drug water solutions and then evaluated by SEM and DSC measurements. The results showed that diosmin was incorporated within the nanofibers in an amorphous state, and/or as a solid dispersion. The results of in vitro release experiments excerpt a very fast release of the drug, followed by the formation of an over saturated solution and partial precipitation of the drug (a "spring" effect). The enormous increases in dissolution of the drug from a nanofibrous carrier, compared to a micronized and crystalline form, was achieved. The in vivo bioavailability study carried out on rats showed higher initial drug plasma levels and higher AUC values after administration of the nanofibrous drug formulation, compared to the micronized form. The results of the study demonstrated that the improvement of the diosmin in vitro dissolution also brought the enhanced in vivo absorption extent of the drug.
- MeSH
- aplikace orální MeSH
- diosmin aplikace a dávkování krev chemie farmakokinetika MeSH
- intestinální absorpce MeSH
- nanovlákna aplikace a dávkování chemie MeSH
- nosiče léků aplikace a dávkování chemie farmakokinetika MeSH
- potkani Wistar MeSH
- příprava léků metody MeSH
- rozpustnost MeSH
- roztoky MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
