A symposium on biomedical properties and applications of dendrimers titled “BIO-Dendrimer 2008” under auspices of His Magnificence Rector of The University of Lodz Professor Wieslaw Pus was held during the period of July 3-5, 2008 in Lodz, Poland. The objective of this conference was to provide a forum for discourse among scientists on the future of dendrimers in medical applications. Over the last few decades dendrimers have developed into one of the most promising research areas of the modern natural sciences. Dendrimers have enormous potential for medical applications. Because of the progress that has recently been made, the time was right to bring together the leading researchers for exchanging expertise, problem solving and future collaborations. Among the participants were scientists from fourteen countries. The symposium had twenty oral presentations and twenty four posters that showed a dramatic variation of topics from basic studies through in vivo experiments to clinical applications. The organizers sorted the communications into four topical areas:
(1)From Synthesis to Applications;
(2)Dendrimers as Carriers – Encapsulation and Conjugation;
(3)Dendrimers as Therapeutics;
(4)Dendrimers in Gene Delivery.
The conference hosted a very good group of international invited speakers who gave memorable talks on the latest results. It was a coup to have Professor Donald A. Tomalia (Central Michigan University, USA) whose introductory lecture entitled “Dendrimer-based nanomedicine: pharma delivery, MRI imaging / targeted / polyvalent therapies” was a comprehensive review on the highlights of using dendrimers as nano-pharmaceutics. He pointed out that dendrimers were referred as “artificial proteins” based on the close mimicry of their dimensions, shapes and surface chemistries to these biological nanostructures. Then the promising therapeutic applications of dendrimers was briefly reported, starting from astonishing anti-inflammatory activity of simple surface functionalized PAMAM dendrimers, finishing with well recognized commercial products such as Stratus, Superfect, Priofect and VivaGel. This theme was picked up in the next keynote lecture given by Professor Jean Pierre Majoral (Laboratoire de Chimie de Coordination CNRS, France), a world authority on synthesis and applications of phosphorus dendrimers. His lecture focused on an exciting property of dendrimers that are able to promote the proliferation of human natural killer cells used in anti-cancer therapy. Natural killer cell infusions have the potential to improve human stem cell transplants in anti-cancer immunotherapy, but till now the selective in vitro amplification of human natural killer cells has been extremely tedious to achieve, therefore preventing the further development of efficient anticancer therapies. In light of this fact phosphorus dendrimers possess fascinating properties being first synthetic reagents able to promote dramatically and selectively the proliferation of human natural killer cells in in vitro cultures with interleukin IL-2. Professor Rene Roy (Université du Québec à Montréal, Canada), an international expert on glycodendrimers brought the audience through several synthetic strategies towards the design of new glycodendrimers based on different scaffolds such as L-lysine, pentaerythritol, 3,5-dihydroxybenzoic acid and hexachloro-cyclotriphophazene as bacterial antiadhesins. Moreover, hybrid glycodendrimers bearing two different saccharides were synthesized in order to simultaneously target two different lectins from the same bacteria. Generally, glycodendrimers, considered as bioisosteres of cell surface multiantennary glycans, are novel families of high affinity ligands towards pathogenic receptors and have been used to block bacterial and viral adhesion to host tissues. Dendrimers are also known as excellent carriers of drugs and genetic material. This topic was raised by Professor Rainer Haag (Free University of Berlin, Germany) who presented his huge experience in developing dendrimers as nanotransporters of anti-cancer drugs and imaging agents and by Professor David Smith (University of York, UK) who showed an impressive example of using spermine as a construction motif of dendrimers that assures high DNA affinity and avoids the toxicity of the vector after delivery of DNA has taken place. Prof. Rainer Haag listed desired properties of good nanotransporters such as water solubility and non-toxicity and presented several new pH-responsive dendritic glycerol-based nanotransporters for delivery of doxorubicin into tumors. The key step of the drug delivery process is the uptake of loaded nanocarriers into the cell. For the uptake of anti-tumor drugs, entry of the nanocarriers in the tumor tissue can be enhanced due to the permeability of tumor blood vessels. In the case of oligonucleotide transfection, uptake is provided by enhanced endocytosis using polycationic dendritic polymers. Professor Maria Francesca Ottaviani (University of Urbino, Italy) is world renowned for applying electronic paramagnetic resonance to study biomedical applications of dendrimers. She demonstrated the latest results obtained in her laboratory e.g. on dendrimers as agents that prevent aggregation of peptides in Alzheimer's disease.
The emerging studies and new developments stimulated lively discussions during the sessions and get-together events such as a welcome reception, a city tour, a grill party and a conference dinner. Since there is a need for such a valuable forum to share expertise it was decided that the conference will be repeated at approximately 2-year intervals covering a gradually expanding scope of medical aspects of dendrimers. The next BIO-Dendrimer symposium will be hosted in Marseille, France by Doctor Ling Peng from Departement de Chimie, CNRS.
BIO-Dendrimer 2008 was very international with guests coming to Poland from such distant countries as USA, Canada and Iran. We hope that this trend will continue.
Local organization was coordinated by Professor Maria Bryszewska, who was the chairperson of the event, with the help of the staff from the Institute of Biophysics, University of Lodz. The symposium would have not be possible without the financial support of following organizations: University of Lodz, Faculty of Biology and Environmental Protection, Ministry of Science and Higher Education, Committee of Biochemistry and Biophysics, Polish Academy of Science, Polish Biophysical Society, City Hall. Last but not least all the participants deserved special thanks for making this event a great success.
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