Source: https://www.nature.com/articles/nri2868?error=cookies_not_supported&code=f6685ab8-edb5-402a-bc90-487429c25525
Timestamp: 2019-04-20 22:25:45+00:00

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Martin F. Bachmann has been Executive Vice President and Chief Scientific Officer of Cytos Biotechnology AG, Zurich, Switzerland, since October 1999. He received his Ph.D. in molecular biology in 1995 at the Institute for Experimental Immunology, Zurich, Switzerland, in the laboratories of Professors Zinkernagel and Hengartner. In 2005, he received a teaching position (Venia Legendi) for immunology from the University of Zurich. He is author of more than 200 articles in internationally renowned scientific journals. His achievements have been honoured with two Swiss Federal Institute of Technology (ETH) Medals (1991 and 1995), the Pfizer Prize for Immunology (1998) and the Swiss Technology Award (2004).
Gary T. Jennings is head of Preclinical Development at Cytos Biotechnology AG and has worked in vaccine research and development for 13 years. He attained his Ph.D. in biochemistry from the University of Western Australia, Perth, Australia, in 1992 and has held postdoctoral positions at the National Cancer Institute, National Institutes of Health, Bethesda, USA, and the University of Texas, San Antonio, USA. In 1998 he joined the IRIS, Chiron Vaccines Società per Azioni in Siena, Italy, and worked in discovery research in the field of reverse vaccinology. For the past 10 years he has worked in the preclinical development of conjugate vaccines for treating chronic diseases.
Vaccine-induced immune responses can be enhanced by mimicking the properties of pathogens.
Most vaccine delivery systems are particulate (including nanoparticles, microparticles or adjuvant-formulated proteins).
The size of the particle systems influences cellular targeting. The most effective sizes are in the 20–200 nm range.
The geometry (that is, repetitiveness) of particle surfaces is crucial for the activation of B cells, as well as for the activation of the innate humoral immune system.
Pathogen-associated molecular patterns (PAMPs) are crucial for the activation of dendritic cells and B cells. Some other receptors of the innate immune system may also be involved in this process.
For effective vaccines, PAMPs should be physically linked to the antigens to enhance their activity and reduce side effects.
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We thank V. Manolova, J. Bessa, T. Kündig, A. Link and P. Saudan for critically reading the manuscript and for their helpful comments.
Research, Cytos Biotechnology AG, Wagistrasse 25, 8952 Schlieren-Zürich, Switzerland.
Martin F. Bachmann and Gary T. Jennings are employees of Cytos Biotechnology AG, Zurich, Switzerland, and hold stocks or stock options in the company.
Correspondence to Martin F. Bachmann.
An adjuvant that forms small particles or droplets and entraps the antigen.
The ability of certain antigen-presenting cells to load peptides that are derived from exogenous antigens onto MHC class I molecules. This property is atypical, because most cells exclusively present peptides from their endogenous proteins on MHC class I molecules. Cross-presentation is essential for the initiation of immune responses to viruses that do not infect antigen-presenting cells.
A complex of antigen bound to antibody and, sometimes, components of the complement system. The levels of immune complexes are increased in many autoimmune disorders, in which they become deposited in tissues and cause tissue damage. To effectively activate complement and Fc receptors, more than one antibody needs to be present in a complex.
A specialized macrophage that resides in the subcapsular sinus of lymph nodes and is efficient at capturing antigen from the lymph.
(FDC). A cell that has a dendritic morphology and is present in lymph nodes. These cells display on their surface intact antigens that are held in immune complexes, and B cells present in the lymph node can interact with these antigens. FDCs are of non-haematopoietic origin and are not related to dendritic cells.
A professional antigen-presenting dendritic cell localized in the epidermis of the skin.
An antigen depot refers to antigen persisting at the site of injection, causing prolonged exposure of the immune system to the antigen. Many adjuvants induce antigen depot formation.
A cell that has a plasma cell-like morphology and produces high levels of type I interferons after exposure to viruses.
A DNA motif rich in non-methylated CG motifs that is mainly found in bacterial or viral DNA and is recognized by Toll-like receptor 9.
A molecule that can bind antibody but cannot elicit an immune response by itself. Antibodies that are specific for a hapten can be generated when the hapten is chemically linked to a protein carrier that can elicit a T cell response.
Co-stimulatory molecules for B cells. CD21 binds complement degradation products, and CD19 is the signal transduction molecule for CD21.
Transient, highly organized multicellular structure present within B cell follicles that is essential for the generation of memory B cells and long-lived plasma cells, as well as for affinity maturation of antibodies.
A specialized T helper cell found in B cell follicles. These cells require interleukin-21 for their development and are specialized in providing help to B cells.

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