Sesquiterpene lactones from the extracts of two Balkan endemic Laserpitium species and their cytotoxic activity

Chloroform extracts of the underground parts of two Balkan endemic Laserpitium species, Laserpitium zernyi Hayek and Laserpitium ochridanum Micevski, were chemically investigated. Five unknown guaianolides from the class of slovanolides, of which four were additionally 2 beta-esterified, as well as two lactones, previously identified in other Laserpitium species, were isolated from the L. ochridanum extract. From the L. zernyi extract one slovanolide derivative was isolated for the first time in the genus Laserpitium. In addition, the phenylpropanoid latifolone and six known sesquiterpene lactones, characterised as derivatives of slovanolide and silerolide, were isolated from the extracts of both species. The cytotoxic activities of the total extracts and the isolated compounds were tested using MTT and SRB assays on the two human breast cancer cell lines, MCF 7/6 and MCF 7/AZ. The extracts exerted cytotoxic activities with the IC50 values ranging 65.21-348.25 mu g/mL. The L ochridanum extract was most potent in the MTT test with IC50 values of 65.21 and 66.09 mu g/mL in the MCF 7/AZ and MCF 7/6 cell lines, respectively. The highest cytotoxic activity exerted 2 beta,8 alpha-di-angeloyloxy-10 beta-hydroxy-6 alpha H-guaian-3,(7-11)-dien-12,6-olide, a slovanolide derivative with an additional double bond in lactone ring, on highly invasive MCF 7/6 cell line, with IC50 value 0.7 mu M in both assays tested. Generally, guaianolides with a higher number of ester moieties at the positions 2 beta, 8 alpha, 10 beta or 11 alpha exhibited IC50 values in the micromolar range, while eudesmanolides and guaianolides with a lower number of esters did not induce significant cytotoxicity

Improvement of different vaccine delivery systems for cancer therapy

Cancer vaccines are the promising tools in the hands of the clinical oncologist. Many tumor-associated antigens are excellent targets for immune therapy and vaccine design. Optimally designed cancer vaccines should combine the best tumor antigens with the most effective immunotherapy agents and/or delivery strategies to achieve positive clinical results. Various vaccine delivery systems such as different routes of immunization and physical/chemical delivery methods have been used in cancer therapy with the goal to induce immunity against tumor-associated antigens. Two basic delivery approaches including physical delivery to achieve higher levels of antigen production and formulation with microparticles to target antigen-presenting cells (APCs) have demonstrated to be effective in animal models. New developments in vaccine delivery systems will improve the efficiency of clinical trials in the near future. Among them, nanoparticles (NPs) such as dendrimers, polymeric NPs, metallic NPs, magnetic NPs and quantum dots have emerged as effective vaccine adjuvants for infectious diseases and cancer therapy. Furthermore, cell-penetrating peptides (CPP) have been known as attractive carrier having applications in drug delivery, gene transfer and DNA vaccination. This review will focus on the utilization of different vaccine delivery systems for prevention or treatment of cancer. We will discuss their clinical applications and the future prospects for cancer vaccine development

Pharmaceutical particles design by membrane emulsification: preparation methods and applications in drug delivery

© 2017 Bentham Science Publishers.Nowadays, the rational design of particles is an important issue in the development of pharmaceutical medicaments. Advances in manufacturing methods are required to design new pharmaceutical particles with target properties in terms of particle size, particle size distribution, structure and functional activity. Membrane emulsification is emerging as a promising tool for the production of emulsions and solidified particles with tailored properties in many fields. In this review, the current use of membrane emulsification in the production of pharmaceutical particles is highlighted. Membrane emulsification devices designed for small-scale testing as well as membrane-based methods suitable for large-scale production are discussed. A special emphasis is put on the important factors that contribute to the encapsulation efficiency and drug loading. The most recent studies about the utilization of the membrane emulsification for preparing particles as drug delivery systems for anticancer, proteins/peptide, lipophilic and hydrophilic bioactive drugs are reviewed

Intranodal administration of mRNA encoding nucleoprotein provides cross-strain immunity against influenza in mice

Background: Current human influenza vaccines lack the adaptability to match the mutational rate of the virus and therefore require annual revisions. Because of extensive manufacturing times and the possibility that antigenic alterations occur during viral vaccine strain production, an inherent risk exists for antigenic mismatch between the new influenza vaccine and circulating viruses. Targeting more conserved antigens such as nucleoprotein (NP) could provide a more sustainable vaccination strategy by inducing long term and heterosubtypic protection against influenza. We previously demonstrated that intranodal mRNA injection can induce potent antigen-specific T-cell responses. In this study, we investigated whether intranodal administration of mRNA encoding NP can induce T-cell responses capable of protecting against a heterologous influenza virus challenge. Methods: BALB/c mice were immunized in the inguinal lymph nodes with different vaccination regimens of mRNA encoding NP. Immune responses were compared with NP DNA vaccination via IFN-gamma ELISPOT and in vivo cytotoxicity. For survival experiments, mice were prime-boost vaccinated with 17 mu g NP mRNA and infected with 1LD50 of H1N1 influenza virus 8weeks after boost. Weight was monitored and viral titers, cytokines and immune cell populations in the bronchoalveolar lavage, and IFN-gamma responses in the spleen were analyzed. Results: Our results demonstrate that NP mRNA induces superior systemic T-cell responses against NP compared to classical DNA vaccination. These responses were sustained for several weeks even at low vaccine doses. Upon challenge infection, vaccination with NP mRNA resulted in reduced lung viral titers and improved recovery from infection. Finally, we show that vaccination with NP mRNA affects the immune response in infected lungs by lowering immune cell infiltration while increasing the fraction of T cells, monocytes and MHC II+ alveolar macrophages within immune infiltrates. This change was associated with altered levels of both pro- and anti-inflammatory cytokines. Conclusions: These findings suggest that intranodal vaccination with NP mRNA induces cross-strain immunity against influenza, but also highlight a paradox of influenza immunity, whereby robust immune responses can provide protection, but can also transiently exacerbate symptoms during infection

Design and evaluation of immunotherapeutic imaging for cancer vaccination

Cancer immunotherapy, where a patient's immune system is harnessed in the battle against a tumor, is currently on the rise. One possible approach comprises the in vitro modulation of dendritic cells with tumor antigens, after which the cells are injected as a therapeutic cancer vaccine. Despite extensive progress and promising (pre)clinical results, such cancer vaccines often remain patient-specific, laborious in production and therefore very expensive. In this thesis, these issues are addressed by developing imageable biomaterials as cancer immunotherapeutics. Firstly, we highlight the use of antigen-loaded perfluorocarbon particles for 19F MRI tracking of dendritic cells is explored. Such imageable cellular vaccines could provide information on the fate and migratory potential of the cells after their injection, and therefore give important initial feedback on the vaccine efficacy. Secondly, we investigated an alternative strategy that makes use of mRNA-loaded microbubbles for ultrasound-guided and ultrasound-triggered immune activation. We demonstrated that this principle could indeed be used to induce antigen expression in dendritic cells in vitro. Moreover, by simultaneously delivering both antigen mRNA and adjuvant mRNA (TriMix), highly immunogenic dendritic cell vaccines could be produced, allowing complete tumor regression in 30% of the vaccinated animals, which were protected against tumor recurrence. Interestingly, these mRNA-loaded microbubbles show potential for the immediate in vivo delivery of mRNA to dendritic cells as they spontaneously migrate to the lymph nodes upon subcutaneous injection. What is more, the image feedback information provided by these contrast agents on the lymphatic anatomy underpins their interesting role as immunotheranostic agents

DNA vaccination for prostate cancer: key concepts and considerations

While locally confined prostate cancer is associated with a low five year mortality rate, advanced or metastatic disease remains a major challenge for healthcare professionals to treat and is usually terminal. As such, there is a need for the development of new, efficacious therapies for prostate cancer. Immunotherapy represents a promising approach where the host’s immune system is harnessed to mount an anti-tumour effect, and the licensing of the first prostate cancer specific immunotherapy in 2010 has opened the door for other immunotherapies to gain regulatory approval. Among these strategies DNA vaccines are an attractive option in terms of their ability to elicit a highly specific, potent and wide-sweeping immune response. Several DNA vaccines have been tested for prostate cancer and while they have demonstrated a good safety profile they have faced problems with low efficacy and immunogenicity compared to other immunotherapeutic approaches. This review focuses on the positive aspects of DNA vaccines for prostate cancer that have been assessed in preclinical and clinical trials thus far and examines the key considerations that must be employed to improve the efficacy and immunogenicity of these vaccines

Different physical delivery systems: An important approach for delivery of biological molecules in vivo

   Delivery of exogenous materials such as nucleic acids, peptides, proteins, and drugs into cells is an important strategy in modern cellular and molecular biology. Recently, the development of gene carriers for efficient gene transfer into cells has attracted a great attention. Furthermore, lack of effective drug delivery is one of the major problems of cancer chemotherapy. Many physical methods have been studied to enhance the efficiency of gene and drug delivery. These strategies help to cross the materials from membranes including needle injection, photodynamic therapy, jet injection, gene gun, electroporation, hydrodynamic injection, laser, magnetofection, and tattooing. The physical systems improve the transfer of genes from extracellular to nucleus by creating transient membrane pores using physical forces including local or rapid systemic injection, particle impact, electric pulse, ultrasound, and laser irradiation. The recent optimization techniques of transdermal patches could improve the transdermal drug delivery through the skin. Among different physical carriers, electroporation and gene gun are the most potent methods for gene transfection and drug delivery in vivo. However, the researchers have focused on enhancing their potency with the structural modifications. Regarding to numerous barriers for biomolecules delivery in cells, this review is concentrated on description and optimization of different physical delivery systems for gene or drug transfer across membrane