Konjugáty protilátka-léčivo (ADC) jsou velmi aktuální terapeutickou skupinou kancerostatik. Tvoří je monoklonální protilátka, nejčastěji typu IgG, na kterou je přes vhodný linker (kovalentní řetězec) konjugována jedna nebo více molekul cytotoxického léčiva. Konjugovaná forma léčiva má výrazně nižší toxicitu než forma volná, kterou v terapii nelze užívat samostatně. Databáze SÚKL registruje zatím 9 ADC přípravků pro použití v onkologii. Vzhledem k tomu, že možných kombinací párů protilátka-léčivo je obrovské množství, do roku 2025 se očekává „boom“ této oblasti a až čtyřnásobný nárůst prodejů. V krevní cirkulaci směřuje ADC přípravek specificky k antigenu přítomnému na povrchu nádorové buňky. Linker mezi protilátkou a léčivem musí být stabilní v prostředí krevní cirkulace a teprve až po internalizaci konjugátu být v cílové nádorové buňce zcela degradován nebo zůstat vázaný na léčivo po degradaci proteinové části konjugátu (tzv. štěpitelné nebo neštěpitelné linkery). Následně léčivo způsobí různými mechanismy apoptózu nádorové buňky. Léčiva použitá v ADC přípravcích 2. generace byla až 1000krát toxičtější než chemoterapeutikum doxorubicin a jednalo se především o deriváty auristatinů a maytansinů. V současné 3. generaci vyvíjených konjugátů se zkouší i méně toxická léčiva na bázi kamptothecinů, amanitinů aj. Léčivo s linkerem je k mAb připojeno pomocí různých biokonjugačních metod. Zde se uplatňuje celá škála technik syntetické chemie, přičemž biokonjugace může být buď nespecifická nebo specifická. Konjugovatelné jsou především periferní aminokyseliny protilátky – cystein, lysin, histidin, tyrosin, glutamin a redukované disulfidové můstky mezi dvěma těžkými nebo mezi těžkým a lehkým řetězcem. Pro specifickou konjugaci byly vyvinuty např. techniky glykoinženýrství, založené na N-glykosylaci protilátky na asparaginu (N297). Konjugační techniky, ale i syntéza „nahé“ humánní mAb jsou předmětem utajovaného „know-how“ řady progresivních firem a laboratoří, které v oblasti ADC přípravků působí.
Antibody-drug conjugates are a promising therapeutic class of cytostatic agents. They consist of a monoclonal antibody, usually of the IgG type, to which one or more molecules of a cytotoxic drug are conjugated via a suitable linker (covalent chain). The conjugated form of the drug has significantly lower toxicity than the free form, which cannot be used alone in therapy. The Czech State Institute for Drug Control database has so far registered 9 antibody-drug conjugates for use in oncology. Given the vast number of possible combinations of antibody-drug pairs, aboom in sales is expected by 2025. In the blood circulation, the antibody-drug conjugate specifically targets the antigen expressed on the surface of the tumor cell. The linker between the antibody and the drug must be stable in the blood circulation environment and only be completely degraded in the target tumor cell after internalization of the conjugate or remain bound to the drug after degradation of the protein part of the conjugate (the so-called cleavable or non-cleavable linkers). Subsequently, the drug causes apoptosis of the tumor cell by various mechanisms. The drugs used in the 2nd generation antibody-drug conjugates were up to 1,000 times more toxic than the chemotherapeutic drug doxorubicin and were mainly auristatin and maytansine derivatives. Less toxic drugs based on camptothecins, amanitins, etc. are also being tested in the current 3rd generation of conjugates under development. The linker drug is attached to the antibody by various bioconjugation methods. Here, a range of synthetic chemistry techniques are applied, and bioconjugation can be either non-specific or specific. In particular, the peripheral amino acids of the antibody – cysteine, lysine, histidine, tyrosine, glutamine and reduced disulfide bridges between the two heavy chains or between the heavy and light chains – are conjugated. For a specific conjugation, e.g. glycoengineering techniques based on N-glycosylation of antibody on asparagine (N297) have been developed. Conjugation techniques, as well as the synthesis of "naked" human antibodies are the subject of classified "know-how" of a number of commercial progressive companies and laboratories.Full text English translation is available in the on-line version.
Konjugáty protilátka-léčivo (ADC) jsou velmi aktuální terapeutickou skupinou kancerostatik. Tvoří je monoklonální protilátka, nejčastěji typu IgG, na kterou je přes vhodný linker (kovalentní řetězec) konjugována jedna nebo více molekul cytotoxického léčiva. Konjugovaná forma léčiva má výrazně nižší toxicitu než forma volná, kterou v terapii nelze užívat samostatně. Databáze SÚKL registruje zatím 9 ADC přípravků pro použití v onkologii. Vzhledem k tomu, že možných kombinací párů protilátka-léčivo je obrovské množství, do roku 2025 se očekává „boom“ této oblasti a až čtyřnásobný nárůst prodejů. V krevní cirkulaci směřuje ADC přípravek specificky k antigenu přítomnému na povrchu nádorové buňky. Linker mezi protilátkou a léčivem musí být stabilní v prostředí krevní cirkulace a teprve až po internalizaci konjugátu být v cílové nádorové buňce zcela degradován nebo zůstat vázaný na léčivo po degradaci proteinové části konjugátu (tzv. štěpitelné nebo neštěpitelné linkery). Následně léčivo způsobí různými mechanismy apoptózu nádorové buňky. Léčiva použitá v ADC přípravcích 2. generace byla až 1000krát toxičtější než chemoterapeutikum doxorubicin a jednalo se především o deriváty auristatinů a maytansinů. V současné 3. generaci vyvíjených konjugátů se zkouší i méně toxická léčiva na bázi kamptothecinů, amanitinů aj. Léčivo s linkerem je k mAb připojeno pomocí různých biokonjugačních metod. Zde se uplatňuje celá škála technik syntetické chemie, přičemž biokonjugace může být buď nespecifická nebo specifická. Konjugovatelné jsou především periferní aminokyseliny protilátky – cystein, lysin, histidin, tyrosin, glutamin a redukované disulfidové můstky mezi dvěma těžkými nebo mezi těžkým a lehkým řetězcem. Pro specifickou konjugaci byly vyvinuty např. techniky glykoinženýrství, založené na N-glykosylaci protilátky na asparaginu (N297). Konjugační techniky, ale i syntéza „nahé“ humánní mAb jsou předmětem utajovaného „know-how“ řady progresivních firem a laboratoří, které v oblasti ADC přípravků působí.
Antibody-drug conjugates are a promising therapeutic class of cytostatic agents. They consist of a monoclonal antibody, usually of the IgG type, to which one or more molecules of a cytotoxic drug are conjugated via a suitable linker (covalent chain). The conjugated form of the drug has significantly lower toxicity than the free form, which cannot be used alone in therapy. The Czech State Institute for Drug Control database has so far registered 9 antibody-drug conjugates for use in oncology. Given the vast number of possible combinations of antibody-drug pairs, aboom in sales is expected by 2025. In the blood circulation, the antibody-drug conjugate specifically targets the antigen expressed on the surface of the tumor cell. The linker between the antibody and the drug must be stable in the blood circulation environment and only be completely degraded in the target tumor cell after internalization of the conjugate or remain bound to the drug after degradation of the protein part of the conjugate (the so-called cleavable or non-cleavable linkers). Subsequently, the drug causes apoptosis of the tumor cell by various mechanisms. The drugs used in the 2nd generation antibody-drug conjugates were up to 1,000 times more toxic than the chemotherapeutic drug doxorubicin and were mainly auristatin and maytansine derivatives. Less toxic drugs based on camptothecins, amanitins, etc. are also being tested in the current 3rd generation of conjugates under development. The linker drug is attached to the antibody by various bioconjugation methods. Here, a range of synthetic chemistry techniques are applied, and bioconjugation can be either non-specific or specific. In particular, the peripheral amino acids of the antibody – cysteine, lysine, histidine, tyrosine, glutamine and reduced disulfide bridges between the two heavy chains or between the heavy and light chains – are conjugated. For a specific conjugation, e.g. glycoengineering techniques based on N-glycosylation of antibody on asparagine (N297) have been developed. Conjugation techniques, as well as the synthesis of "naked" human antibodies are the subject of classified "know-how" of a number of commercial progressive companies and laboratories.
The text is a contemporary continuation of an earlier publication, Kratochvíl B.: Chem. Listy 101, 3 (2007). It describes mainly the nucleation process (two-step nuclea-tion of active substances in pharmacy) and crystallization control processes (seeded crystallization and sonocrystalli-zation). The focus of the work is the description of the nucleation process monitoring by modern analytical tech-nologies, i.e., Focused Beam Reflectance Measurement (FBRM) and the BlazeMetrics system. Both methods pres-ently provide the best available information for a deeper understanding of the nucleation process mechanism in crystallizing active substances. The work is documented by high quality and original photographic attachments of the crystallizing material.Full text English translation is available in the on-line version.
- Klíčová slova
- systém Blaze, nukleace,
- MeSH
- farmaceutická technologie klasifikace metody přístrojové vybavení MeSH
- krystalizace * klasifikace metody přístrojové vybavení MeSH
- lasery MeSH
- výzkumný projekt MeSH
- Publikační typ
- přehledy MeSH
The text is a contemporary continuation of an earlier publication, Kratochvíl B.: Chem. Listy 101, 3 (2007). It describes mainly the nucleation process (two-step nuclea-tion of active substances in pharmacy) and crystallization control processes (seeded crystallization and sonocrystalli-zation). The focus of the work is the description of the nucleation process monitoring by modern analytical tech-nologies, i.e., Focused Beam Reflectance Measurement (FBRM) and the BlazeMetrics system. Both methods pres-ently provide the best available information for a deeper understanding of the nucleation process mechanism in crystallizing active substances. The work is documented by high quality and original photographic attachments of the crystallizing material.
- Klíčová slova
- systém Blaze, nukleace,
- MeSH
- farmaceutická technologie klasifikace metody přístrojové vybavení MeSH
- krystalizace * klasifikace metody přístrojové vybavení MeSH
- lasery MeSH
- výzkumný projekt MeSH
- Publikační typ
- přehledy MeSH
A highly effective way to improve prognosis of viral infectious diseases and to determine the outcome of infection is early, fast, simple, and efficient diagnosis of viral pathogens in biological fluids. Among a wide range of viral pathogens, Flaviviruses attract a special attention. Flavivirus genus includes more than 70 viruses, the most familiar being dengue virus (DENV), Zika virus (ZIKV), and Japanese encephalitis virus (JEV). Haemorrhagic and encephalitis diseases are the most common severe consequences of flaviviral infection. Currently, increasing attention is being paid to the development of electrochemical immunological methods for the determination of Flaviviruses. This review critically compares and evaluates recent research progress in electrochemical biosensing of DENV, ZIKV, and JEV without labelling. Specific attention is paid to comparison of detection strategies, electrode materials, and analytical characteristics. The potential of so far developed biosensors is discussed together with an outlook for further development in this field.
- MeSH
- biosenzitivní techniky * MeSH
- dengue * diagnóza MeSH
- Flavivirus * MeSH
- infekce virem zika * diagnóza MeSH
- japonská encefalitida * diagnóza MeSH
- lidé MeSH
- virus zika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
This work reports for the first time a significantly improved and simplified electrochemical immunoassay to detect antibodies to tick-borne encephalitis virus (TBEV) using a 96-well microtiter plate as a platform for immobilization and silver nanoparticles (AgNPs) as electrochemical labels. The electrochemical assay is performed by detecting the elemental silver oxidation signal where the electroactive signalling silver species are released from the bioconjugates (Ab@AgNP, AbS@AgNP, and ProteinA@AgNP). For this purpose, AgNPs were synthesized and further tagged with biomolecules (antibodies to TBEV, cleaved antibodies to TBEV, and protein A). Signal is read by linear sweep anodic stripping voltammetry (LSASV) of silver ions (through the electrochemical stripping of accumulated elemental silver) on a graphite electrode (GE). AbS@AgNP was chosen as the best option for the new electrochemical immunoassay. The results of electrochemical measurements demonstrated that voltammetric signal increased with the increasing concentration of target antibodies to TBEV within the range from 100 to 1600 IU mL-1, with a detection limit of 90 IU mL-1. To verify the practical application of the novel electrochemical immunosensor, the quantity of immunoglobulins against TBEV in human serum was checked. The results may contribute to the development of alternative methods for monitoring TBEV in biological fluids.
- MeSH
- elektrochemické techniky metody MeSH
- imunoanalýza metody MeSH
- klíšťová encefalitida diagnóza virologie MeSH
- kovové nanočástice chemie MeSH
- lidé MeSH
- protilátky virové analýza MeSH
- stříbro chemie MeSH
- viry klíšťové encefalitidy imunologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
A highly effective way to improve the prognosis of viral infectious diseases is early detection of antibodies to various viral pathogens in biological fluids. Among a wide range of viral pathogens, tick-borne encephalitis virus (TBEV) attracts a special attention. This work reports a comparison between two bioanalytical methods (enzyme‑linked immunosorbent assay (ELISA) and voltammetric immunoassay) to determine antibodies to TBEV in a human blood serum. In these assays, the detected molecule binds to the conjugate which is labelled with enzyme (in ELISA) or silver nanoparticles (in voltammetric immunoassay). In the ELISA, the signal corresponding to a colour-producing substrate (3,3',5,5'-tetramethylbenzidine) through an enzymatic reaction is detected using a spectrophotometer at a wavelength of 450 nm. In the electrochemical immunoassay, the signal is read by the linear sweep anodic stripping voltammetry (LSASV) of silver ions (through the electrochemical stripping of accumulated elemental silver) on a graphite composite electrode. The results of both measurements demonstrated that signals increased with the increasing concentration of the target antibodies to TBEV within the range from 100 to 1600 IU mL–1. Detection limits for ELISA and voltammetric assay were 30 and 90 IU mL–1, respectively. The practical application of both immunoanalytical approaches has been verified by determining the amount of antibodies to TBEV in the human blood serum. The obtained results clearly showed an excellent agreement between the detected concentration values of antibodies to TBEV obtained by the electrochemical method and by the standard ELISA method.
There has been a great interest in solid dispersions since 60's because it is one of the most promising methods to increase the low bioavailability of poorly water soluble drugs. Numerous studies on solid dispersions have been published, showing advantages of these materials. The main benefits of solid dispersions for low soluble drugs lie in the possibility to reduce the particle size, even to molecular level, to enhance wettability and porosity, as well as to change the drug crystalline state, preferably into amorphous state. Despite high research interests, the number of marketed products with solid dispersion is surprisingly low. The aim of this review is to provide basic information for better understanding of solid dispersions. The article contains definitions and characterization of the various system including four generations of solid dispersions, description of preparation methods and mechanisms of drug dissolution.
An aminoborane side product from the nicergoline manufacture process was identified by single-crystal X-ray diffraction. As boranes of pharmaceutical molecules are quite rare, the binding potential of the BH3 group was investigated and compared with similar compounds using Cambridge Structural Database (CSD). Surprisingly, the packing was stabilized by a dihydrogen bond, which triggered a false alert for too-short contact of hydrogen atoms in IUCR checkCIF. As the dihydrogen bond concept is not widely known, such an alert might mislead crystallographers to force -CH3 optimal geometry to -BH3 groups. The B-H distances equal to or less than 1.0 Å (17% of the CSD structures) are substantially biased when analyzing the structures of aminoborane complexes in CSD. To conduct proper searching, B-H bond length normalization should be applied in the CSD search.
A new simple electrochemical immunosensor approach for the determination of antibodies to tick-borne encephalitis virus (TBEV) in immunological products was developed and tested. The assay is performed by detecting the silver reduction signal in the bioconjugates with antibodies (Ab@AgNP). Here, signal is read by cathodic linear sweep voltammetry (CLSV) through the detection of silver chloride reduction on a gold-carbon composite electrode (GCCE). Covalent immobilization of the antigen on the electrode surface was performed after thiolation and glutarization of the GCCE. Specific attention has been paid to the selection of conditions for stabilizing both the silver nanoparticles and their Ab@AgNP. A simple flocculation test with NaCl was used to select the concentration of antibodies, and the additional stabilizer bovine serum albumin (BSA) was used for Ab@AgNP preparation. The antibodies to TBEV were quantified in the range from 50 IU·mL-1 to 1600 IU·mL-1, with a detection limit of 50 IU·mL-1. The coefficient of determination (r2) is 0.989. The electrochemical immunosensor was successfully applied to check the quality of immunological products containing IgG antibodies to TBEV. The present work paves the path for a novel method for monitoring TBEV in biological fluids.
- MeSH
- elektrochemické techniky metody MeSH
- elektrody MeSH
- imunoanalýza metody MeSH
- klíšťová encefalitida diagnóza imunologie MeSH
- kovové nanočástice chemie ultrastruktura MeSH
- protilátky virové imunologie MeSH
- sérový albumin hovězí MeSH
- skot MeSH
- spektrofotometrie ultrafialová MeSH
- stříbro chemie MeSH
- velikost částic MeSH
- viry klíšťové encefalitidy imunologie MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
