Search results

1

Virus-like particles as drug delivery vectors

100%

Zdanowicz M., Chroboczek J.

Acta Biochimica Polonica

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2016

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vol. 63

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issue 3

469-473

EN

Virus-like particles (VLPs) assemble spontaneously during the viral cycle or in heterologous systems during expression of viral structural protein. Depending on the complexity of the VLPs, they can be obtained by expression in prokaryotic or eukaryotic expression system from the suitable recombinant vectors, or formed in cell-free conditions. Moreover, they can be built from proteins of a single virus, or can present the proteins or peptides derived from a virus or cell on a platform derived from any other single virus, thus forming chimeric VLPs. VLPs are best known for their immunogenic properties, but the versatility of VLPs allows a wide variety of applications. They are lately in the centre of investigations in vaccinology, drug delivery and gene therapy. This review focuses on utilization of VLPs for drug delivery.

2

Engineered resistance against proteinases

81%

Milner M., Chroboczek J., Zagorski-Ostoja W.

Acta Biochimica Polonica

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2007

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vol. 54

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issue 3

523-536

EN

Exogenous proteinase inhibitors are valuable and economically interesting protective biotechnological tools. We examined whether small proteinase inhibitors when fused to a selected target protein can protect the target from proteolytic degradation without simultaneously affecting the function and activity of the target domain. Two proteinase inhibitors were studied: a Kazal-type silk proteinase inhibitor (SPI2) from Galleria mellonella, and the Cucurbita maxima trypsin inhibitor I (CMTI I). Both inhibitors target serine proteinases, are small proteins with a compact structure stabilized by a network of disulfide bridges, and are expressed as free polypeptides in their natural surroundings. Four constructs were prepared: the gene for either of the inhibitors was ligated to the 5' end of the DNA encoding one or the other of two selected target proteins, the coat protein (CP) of Potato potyvirus Y or the Escherichia coli β-glucuronidase (GUS). CMTI I fused to the target proteins strongly hampered their functions. Moreover, the inhibitory activity of CMTI I was retained only when it was fused to the CP. In contrast, when fused to SPI2, specific features and functions of both target proteins were retained and the inhibitory activity of SPI2 was fully preserved. Measuring proteolysis in the presence or absence of either inhibitor, we demonstrated that proteinase inhibitors can protect target proteins used either free or as a fusion domain. Interestingly, their inhibitory efficiency was superior to that of a commercial inhibitor of serine proteinases, AEBSF.

3

Virus-like particles as vaccine

81%

Chroboczek J., Szurgot I., Szolajska E.

Acta Biochimica Polonica

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2014

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vol. 61

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issue 3

531-539

EN

This review presents data on commercial and experimental virus-like particle (VLP) vaccines, including description of VLP vaccines against influenza. Virus-like particles are multimeric, sometimes multiprotein nanostructures assembled from viral structural proteins and are devoid of any genetic material. VLPs present repetitive high-density displays of viral surface proteins. Importantly, they contain functional viral proteins responsible for cell penetration by the virus, ensuring efficient cell entry and thus tissue-specific targeting, determined by the origin of the virus. The foremost application of VLPs is in vaccinology, where they provide delivery systems that combine good safety profiles with strong immunogenicity and constitute a safe alternative to inactivated infectious viruses. These stable and versatile nanoparticles display excellent adjuvant properties capable of inducing innate and cognate immune responses. They present both, high-density B-cell epitopes, for antibody production and intracellular T- cell epitopes, thus inducing, respectively, potent humoral and cellular immune responses. Uptake of VLPs by antigen-presenting cells leads to efficient immune responses resulting in control of pathogenic microorganisms.

4

Phosphorylation of wheat germ ribosomes in vitro by wheat germ protein kinase

81%

Chroboczek J., Madjar J.-J., Rychlik W., Zagórski W.

Acta Biochimica Polonica

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1982

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vol. 29

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issue 1-2

135-141

5

Structural proteins of adenovirus. Expression in Escherichia coli

71%

Chroboczek J., Chatellard C., Rizo C., Cuillel M., Jacrot B.

Acta Biochimica Polonica

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1990

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vol. 37

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issue 1

39-52

6

The host cell fraction that increases the infectivity of bacteriophage f2

70%

Chroboczek J.

Acta Biochimica Polonica

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1978

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vol. 25

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issue 1

37-47

7

Analysis of potyvirus terminal protein VPg-transgenic Arabidopsis thaliana plants

61%

Wojtal I., Piontek P., Grzela R., Jarmołowski A., Zagórski W., Chroboczek J.

Acta Biochimica Polonica

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2011

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vol. 58

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issue 3

349-353

EN

Virus-coded VPg protein of Potato virus Y (PVY) does not have homologs apart from other VPgs. Since VPg is indispensable for the potyvirus life cycle, it appeared a good candidate for eliciting pathogen-derived resistance to PVY. Following agroinfection used to obtain PVY VPg-transgenic Arabidopsis thaliana plants, only few transgenic seeds were recovered giving rise to six transgenic plants that contained the VPg gene with the correct sequence. They generated VPg mRNA, but VPg protein was not detected. Some plants were immune to PVY infection suggesting post-transcriptional gene silencing. However, the likely PVY VPg toxicity exerted at an early stage of transformed seeds development precludes its use for engineering pathogen-derived resistance.

8

Certain protein transducing agents convert translocated proteins into cell killers

52%

Tcherniuk S., Fiser A.-L., Derouazi M., Toussaint B., Wang Y., Wojtal I., Kondo E., Szolajska E., Chroboczek J.

Acta Biochimica Polonica

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2012

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vol. 59

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issue 3

433-439

EN

The majority of proteins are unable to translocate into the cell interior. Hence for peptide- and protein-based therapeutics a direct intracytoplasmic delivery with the aid of transducing agents is an attractive approach. We wanted to deliver to the cell interior a putatively cytotoxic protein VPg. Protein transduction was achieved in vitro with three different commercial products. However, in our hands, delivery of various control proteins without known deleterious effects, as well as of protein VPg, always induced cell death. Finally, we used a novel transducing peptide Wr-T, which was not toxic to cultured cells, even in a quite large range of concentrations. Most importantly, control protein delivered to cells in culture did not display any toxicity while VPg protein exerted a strong cytotoxic effect. These data show that results obtained with cell-penetrating agents should be interpreted with caution.

Refine search results

Virus-like particles as drug delivery vectors

Engineered resistance against proteinases

Virus-like particles as vaccine

Phosphorylation of wheat germ ribosomes in vitro by wheat germ protein kinase

Structural proteins of adenovirus. Expression in Escherichia coli

The host cell fraction that increases the infectivity of bacteriophage f2

Analysis of potyvirus terminal protein VPg-transgenic Arabidopsis thaliana plants

Certain protein transducing agents convert translocated proteins into cell killers