When immune cells detect harmful pathogens or cancer, they mobilize and coordinate a competent defense reaction. To achieve this effectively, immune cells must communicate in a way that is tailored to the pathogenic infestation. Thus, the body's response to various health challenges depends on successful coordination between the cells of the immune system.
The major players in the immune system include helper T cells and antigen-presenting cells such as dendritic cells and the antibody-producing B cells. T cells communicate with antigen-presenting cells via short-lived contacts called immune synapses. These contacts are highly specialized foundation cells with the appropriate platform for the timely and efficient exchange of information. Key messages are sent through the nano-sized vesicles called synaptic ectosomes via the immune synapse.
Research by Prof. Mike Dustin of the Kennedy Institute of Rheumatology at the University of Oxford has tracked the movement of ectosomes and decoded their contents. As described in the research results published in eLIFE, the team developed a three-dimensional synthetic cell and successfully intercepted and decoded the messages contained in T-helper-derived ectosomes. Super-resolution microscopy, called dSTORM, has been used in these studies to find that these synaptic T-cell ectosomes have a size scale of one millionth of a meter, but despite their reduced size, can pack enough information to support the response of dendritic cells orchestrate. In addition, cell-free ectosomes and their synthetically engineered versions lead to the maturation of dendritic cells, an essential process for establishing adequate immune responses.
In dSTORM experiments it was further demonstrated how both antigen recognition and effector functions in individual ectosomes can grow together through T cells is mediated, is very targeted. Finally, using mass spectrometry and CRISPR-Cas9 gene technology, the team investigated the key molecular mechanisms known as ESCRT proteins responsible for the delivery of helper T cell ectosomes.
These ectosomes depend on direct molecular interactions at the immune synapse and have profound implications for the understanding of cell-to-cell communication, "said co-lead author of the study, Dr. David Saliba, said using this new knowledge is important for the development of future therapies that can help to influence the immune response to certain diseases.
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David G. Saliba et al., Composition and Structure of Synaptic Ectosomes Exporting an Antigen Receptor Bound to a Functional CD40 Ligand from T Helper Cells eLife (201
Synthetic Cells Capture and Reveal Hidden Immune System Messages (2019, September 17)
September 17, 2019 retrieved
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