Novel mechanism that enables CD4 T cells to selectively induce expression of cytokines. Study by the Fackler laboratory at University Hospital Heidelberg, Germany.
The success of immune reactions in response to pathogen infection critically depends on the generation of high affinity antibodies that can neutralize the infection.
This important task involves complex interactions between different types of immune cells, including support of antibody-producing B cells from CD4 T cells (T cell help).
This helper function of CD4 T cells relies on the release of specific messenger molecules (cytokines), whose production is rapidly initiated when CD4 T cells are activated upon recognition of an infection the immune system.
A new study by the Fackler laboratory at University Hospital Heidelberg, Germany - published in Science Immunology on January 4 - identified a novel mechanism that enables CD4 T cells to selectively induce expression of the cytokines required to drive antibody production by B cells.
Dr. Tsopoulidis, the lead author of the study, focused on the behavior of the actin cytoskeleton in CD4 T cells upon their activation.
The actin cytoskeleton is a dynamic structure that allows polymerizing actin monomers into long filaments, a process used to organize cell shape, motility and communication.
While these established roles of the actin cytoskeleton are exerted in the cytoplasm of cells, Tsopoulidis and colleagues observed that CD4 T cell activation also induces the rapid formation of an actin filament network in their nucleus.
Dissecting the molecular mechanisms involved in the formation of this mesh of nuclear actin filaments enabled the authors to design experiments to study how CD4 T cell activation fares in the absence of nuclear actin filaments in tissue culture and in mice.
To their surprise, the results of these studies revealed that nuclear actin filaments are important regulators of the expression of specifically those cytokines required by B cells for efficient production of antibodies.
“How T cell activation triggers the production of only a specific set of cytokines has been a long-standing question in the field. Our results reveal that nuclear actin filaments act as important regulators of this process and it will be exiting to study the underlying mechanisms” explains Prof. Fackler.
In addition to identifying nuclear actin polymerization as new mechanism involved in T cell activation, these findings have translational potential.
“Chimeric-antigen receptor (CAR) T cell therapy is a very promising approach for the treatment of many cancers, however often paralleled by side effects due to overshooting production of CD4 T cell cytokines. Specific interference with nuclear actin polymerization may help to alleviate these problems” says Dr. Tsopoulidis.
Prof. Oliver T. Fackler
Zentrum für Infektiologie
Center for Integrative Infectious Disease Research (CIID)
University Hospital Heidelberg
Tsopoulidis N, Kaw S, Laketa V, Kutscheidt S, Baarlink C, Stolp B, Grosse R, Fackler OT. T cell receptor-triggered nuclear actin network formation drives CD4+ T cell effector functions. Sci Immunol. 2019 4: eaav1987. doi: 10.1126/sciimmunol.aav1987.
https://www.klinikum.uni-heidelberg.de/Fackler.6555.0.html research group Fackler
Julia Bird | idw - Informationsdienst Wissenschaft
An ion channel with a doorkeeper: The pH of calcium ions controls ion channel opening
25.06.2019 | Johannes Gutenberg-Universität Mainz
Symbiotic upcycling: Turning “low value” compounds into biomass
25.06.2019 | Max-Planck-Institut für Marine Mikrobiologie
From June 25th to 27th 2019, the Fraunhofer Institute for Digital Media Technology IDMT in Ilmenau (Germany) will be presenting a new solution for acoustic quality inspection allowing contact-free, non-destructive testing of manufactured parts and components. The method which has reached Technology Readiness Level 6 already, is currently being successfully tested in practical use together with a number of industrial partners.
Reducing machine downtime, manufacturing defects, and excessive scrap
The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.
Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...
The well-known representation of chemical elements is just one example of how objects can be arranged and classified
The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...
Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.
Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...
Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.
The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...
24.06.2019 | Event News
29.04.2019 | Event News
17.04.2019 | Event News
25.06.2019 | Architecture and Construction
25.06.2019 | Life Sciences
25.06.2019 | Power and Electrical Engineering