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Lukawska M.,Institute of Biotechnology and Antibiotics | Wietrzyk J.,Institute of Immunology and Experimental Therapy | Opolski A.,Institute of Immunology and Experimental Therapy | Oszczapowicz J.,University of Warsaw | Oszczapowicz I.,Institute of Biotechnology and Antibiotics
Investigational New Drugs | Year: 2010

Summary: Oxazolinodaunorubicin, a new daunorubicin derivative with a modified daunosamine moiety, was synthesized. The biological properties of this derivative and the parent daunorubicin were compared. The results showed antiproliferative activity of the derivative with significantly lower toxicity (an LD50 value ca. 20 times higher than that of parent daunorubicin) and an ability to completely overcome the resistance of cancer cells to this drug in vitro. Cardiotoxicity determination using male mice treated with a single dose of 75% of the LD50 value indicated that the cardiotoxicity of new analog was much lower than that of the parent drug. Preliminary results in transplanted murine tumor models revealed that a single-dose injection of the tested compounds exhibited antitumor activity in P388 and L1210 leukemia and 16/C mammary adenocarcinoma bearing mice. © 2009 Springer Science+Business Media, LLC.


Kapusta J.,Institute of Biotechnology and Antibiotics | Kapusta J.,Polish Academy of Sciences | Pniewski T.,Polish Academy of Sciences | Wojciechowicz J.,Research Center | And 2 more authors.
Archivum Immunologiae et Therapiae Experimentalis | Year: 2010

Mucosal immunity elicited by plant-based and other orally administered vaccines can serve as the first line of defense against most pathogens infecting through mucosal surfaces, but it is also considered for systemic immunity against blood-borne diseases such as hepatitis B (HB). Previous oral immunization trials based on multiple administration of high doses of HBs antigen elicited an immune response; however, a reproducible and long-lasting immunization protocol was difficult to design. The objective of this study was to evaluate the effect of dose and timing of orally delivered alum-adsorbed antigen on the magnitude of the anti-HBs humoral response. Mice were immunized orally by gavage intubation or parenterally by intramuscular injection three times, once every 2 weeks, with doses of 5, 50, or 500 ng alum-adjuvanted HBsAg. A low dose (10 ng) of HBsAg was orally administered three times in different time intervals: 2, 4, 6, and 8 weeks. The three consecutive 5-ng oral doses of the antigen induced immune response at the protective level (≥10 mIU/ml), significantly higher than the reaction elicited by three 50 or 500 ng doses. In contrast, intramuscular delivery of these doses did not differ significantly; however, they induced a five to six times higher immune response than oral immunization. The 8-week period between each of the three oral immunizations appeared to be favorable to the anti-HBs humoral responses compared with the shorter schedules. The results presented here clearly identify the importance of low doses of antigen administered orally in extended intervals for a significantly higher anti-HBs response. This finding provides some indications concerning the strategy of orally administered vaccines, including plant-based ones. © 2010 L. Hirszfeld Institute of Immunology and Experimental Therapy, Wroclaw, Poland.


Smorawinska M.,Institute of Biotechnology and Antibiotics | Szuplewska M.,University of Warsaw | Zaleski P.,Institute of Biotechnology and Antibiotics | Wawrzyniak P.,Institute of Biotechnology and Antibiotics | And 3 more authors.
FEMS Microbiology Letters | Year: 2012

Klebsiella pneumoniae 287-w carries three small narrow host range (NHR) plasmids (pIGMS31, pIGMS32, and pIGRK), which could be maintained in several closely related species of Gammaproteobacteria, but not in Alphaproteobacteria. The plasmids contain different mobilization systems (MOB), whose activity in Escherichia coli was demonstrated in the presence of the helper transfer system originating from plasmid RK2. The MOBs of pIGMS31 and pIGMS32 are highly conserved in many bacterial plasmids (members of the MOB family), while the predicted MOB of pIGRK has a unique structure, encoding a protein similar to phage-related integrases. The MOBs of pIGMS31 and pIGMS32 enabled the transfer of heterologous replicons from E. coli into both gammaproteobacterial and alphaproteobacterial hosts, which suggests that these NHR plasmids contain broad host range MOB systems. Such plasmids therefore represent efficient carrier molecules, which may act as natural suicide vectors promoting the spread of diverse genetic information (including other types of mobile elements, e.g. resistance transposons) among evolutionarily distinct bacterial species. Thus, mobilizable NHR plasmids may play a much more important role in horizontal gene transfer than previously thought. © 2011 Federation of European Microbiological Societies.


Babenko V.,University of Warsaw | Surmacz-Chwedoruk W.,Institute of Biotechnology and Antibiotics | Dzwolak W.,University of Warsaw
Langmuir | Year: 2015

Formation of amyloid fibrils is often facilitated in the presence of specific charge-compensating ions. Dissolved sodium chloride is known to accelerate insulin fibrillation at low pH that has been attributed to the shielding of electrostatic repulsion between positively charged insulin molecules by chloride ions. However, the subsequent fate of Cl- anions; that is, possible entrapment within elongating fibrils or escape into the bulk solvent, remains unclear. Here, we show that, while the presence of NaCl at the onset of insulin aggregation induces structural variants of amyloid with distinct fingerprint infrared features, a delayed addition of salt to fibrils that have been already formed in its absence and under quiescent conditions triggers a "condensation effect": amyloid superstructures with strong chiroptical properties are formed. Chloride ions appear to stabilize these superstructures in a manner similar to stabilization of DNA condensates by polyvalent cations. The concentration of residual chloride ions trapped within bovine insulin fibrils grown in 0.1 M NaCl, at pD 1.9, and rinsed extensively with water afterward is less than 1 anion per 16 insulin monomers (as estimated using ion chromatography) implying absence of defined solvent-sequestered nesting sites for chloride counterions. Our results have been discussed in the context of mechanisms of insulin aggregation. © 2015 American Chemical Society.


Surmacz-Chwedoruk W.,Institute of Biotechnology and Antibiotics | Surmacz-Chwedoruk W.,Polish Academy of Sciences | Nieznanska H.,Nencki Institute of Experimental Biology | Wojcik S.,University of Warsaw | Dzwolak W.,University of Warsaw
Biochemistry | Year: 2012

The irreversibility and autocatalytic character of amyloidogenesis and the polymorphism of amyloid fibrils underlie the phenomenon of self-propagating strains, wherein the mother seed, rather than the seeding environment, determines the properties of daughter fibrils. Here we study the formation of amyloid fibrils from bovine insulin and the recombinant LysB31- ArgB32 human insulin analog. The two polypeptides are similar enough to cross-seed but, upon spontaneous aggregation, form amyloid fibrils with distinct spectral features in the infrared amide I′ band region. When bovine insulin is cross-seeded with the analog amyloid (and vice versa), the shape, absorption maximum, and even fine fingerprint features of the amide I′ band are passed from the mother to daughter fibrils with a high degree of fidelity. Although the differences in primary structure between bovine insulin and the LysB31-ArgB32 analog of human insulin lie outside of the polypeptides critical amyloidogenic regions, they affect the secondary structure of fibrils, possibly the formation of intermolecular salt bridges, and the susceptibility to dissection and denaturation with dimethyl sulfoxide (DMSO). All these phenotypic features of mother fibrils are imprinted in daughter amyloid upon cross-seeding. Analysis of noncooperative DMSO-induced denaturation of daughter fibrils suggests that the self-propagating polymorphism underlying the emergence of new amyloid strains is encoded on the level of secondary structure. Our findings have been discussed in the context of polymorphism of fibrils, amyloid strains, and possible implications for mechanisms of amyloidogenesis. © 2012 American Chemical Society.


Dzwolak W.,University of Warsaw | Surmacz-Chwedoruk W.,Institute of Biotechnology and Antibiotics | Surmacz-Chwedoruk W.,Polish Academy of Sciences | Babenko V.,University of Warsaw
Langmuir | Year: 2013

Formation of amyloid fibrils is often associated with intriguing far-from-equilibrium phenomena such as conformational memory effects or flow-driven self-assembly. Insulin is a model amyloidogenic polypeptide forming distinct structural variants of fibrils, which self-propagate through seeding. According to infrared absorption, fibrils from bovine insulin ([BI]) and LysB31-ArgB32 human insulin analogue ([KR]) cross-seed each other and imprint distinct structural features in daughter fibrils. In the absence of preformed [KR] amyloid seeds, bovine insulin agitated at 60 C converts into chiral amyloid superstructures exhibiting negative extrinsic Cotton effect in bound thioflavin T. However, when agitated bovine insulin is simultaneously cross-seeded with [KR] amyloid, daughter fibrils reveal a positive extrinsic Cotton effect. Our study indicates that dramatic changes in global properties of amyloid superstructures may emerge from subtle conformational-level variations in single fibrils (e.g., alignment and twist of β-strands) that are encoded by memory effects. © 2012 American Chemical Society.


Majzner K.,Jagiellonian University | Wojcik T.,Jagiellonian University | Szafraniec E.,Jagiellonian University | Lukawska M.,Institute of Biotechnology and Antibiotics | And 3 more authors.
Analyst | Year: 2015

Anthracycline antibiotics display genotoxic activity towards cancer cells but their clinical utility is limited by their cardiac and vascular toxicity. The aim of this study was to develop a Raman-based methodology to study the nuclear accumulation of anthracyclines in the endothelium. For this purpose bimodal confocal Raman and fluorescence imaging was used to monitor cellular composition changes as a result of anthracycline exposure on endothelial cells (EA.hy926), and nuclear drug accumulation, respectively. Simultaneously effects of anthracyclines on endothelium viability were investigated by caspases-3 and -7 and MTT assays. We demonstrated that nuclear accumulation of DOX and EDOX was similar; however, EDNR accumulated in endothelial nuclei at concentrations 10 times higher than DNR. In turn, epimers of DOX or DNR were both consistently less toxic on the endothelium as compared to their congeners as evidenced by MTT and caspase assays. In summary, bimodal Raman and fluorescence-based nucleus profiling proves to be a valuable tool to study structure-activity relationship of nuclear accumulation and toxicity of anthracyclines in endothelium. © The Royal Society of Chemistry 2015.


Stojak M.,Jagiellonian University | Mazur L.,Jagiellonian University | Opydo-Chanek M.,Jagiellonian University | Ukawska M.,Institute of Biotechnology and Antibiotics | Oszczapowicz I.,Institute of Biotechnology and Antibiotics
Anticancer Research | Year: 2013

Background/Aim: The comparative effects of daunorubicin, and its new formamidine derivatives containing either a morpholine moiety (DAUFmor) or a hexamethyleneimine moiety (DAUFhex) in the amidine group, on induction of programmed cell death were determined. Materials and Methods: The experiments were performed on human acute lymphoblastic leukemia MOLT-4 cells and human acute myeloblastic leukemia ML-1 cells. The research was conducted using the flow cytometry annexin V-fluorescein (FITC)/propidium iodide (PI) method and tetramethylrhodamine ethyl ester (TMRE) assay. Results: The various patterns of temporary changes of early apoptotic cells, late apoptotic and necrotic cells, and in the frequency of the acute leukemia cells with high values of mitochondrial membrane potential (MMP) were found. Phosphatidylserine externalization, plasma membrane disruption, and changes in MMP occurring in the leukemia cells were dependent on the agent tested, its concentration, the time intervals after daunorubicin, DAUFmor, and DAUFhex application, and on the leukemia cell line used. Conclusion: The structural modifications of daunorubicin producing two new analogs, DAUFmor and DAUFhex, induced the different responses of MOLT-4 and ML-1 cells to triggering of programmed death.


Saczynska V.,Institute of Biotechnology and Antibiotics
Acta Biochimica Polonica | Year: 2014

Recombinant subunit vaccines based on hemagglutinin proteins produced in bacteria (bacterial HAs) are promising candidates for enhancing the supply of vaccines against influenza, especially for a pandemic. Over 20 years after the failure to obtain the antigen with native HA characteristics in the early 1980's, there are increasing data on successful production of HA proteins in bacteria. The vast majority of bacterial HAs have been based on the HA1 subunit of HA expressed separately or as a component of conjugate vaccines, but those based on the ectodomain and the HA2 subunit have also been reported. The most of HAs have been efficiently expressed as insoluble aggregates called inclusion bodies. Refolded and purified proteins were extensively studied for structure, the ability to bind to sialic acid-containing receptors, antigenicity, immunogenicity and efficacy. The results from these studies contradict the view that glycosylation determines the correct structure of the hemagglutinin, as they proved that bacterial HAs can be valuable vaccine antigens when appropriate folding and purification methods are applied to rationally designed proteins. The best evidence for success in bacterial production of protective HA is that vaccines based on proprietary Toll-like Receptor (VaxInnate) and bacteriophage Qß-VLPs (Cytos Biotechnology) technologies have been advanced to clinical studies.


Kesik-Brodacka M.,Institute of Biotechnology and Antibiotics | Plucienniczak G.,Institute of Biotechnology and Antibiotics
Acta Biochimica Polonica | Year: 2014

Influenza is a global health concern. The single most effective way of protecting people against influenza infection and disease is vaccination. However, currently available vaccines against influenza induce only strain-specific immunity, and do not elicit long-lasting serum antibody titers. Therefore, they are ineffective in the case of possible pandemics. There is an urgent need for a new generation vaccine which would induce broad and long-lasting immune protection against antigenically distinct flu viruses. The paper presents recent achievements and the challenges in the field of universal vaccine construction.

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