Reporting in the Proceedings of the National Academy of Sciences, a team of Jefferson immunologists found that a specialized “human immune system” mouse model closely mimics a person’s specific response and resolution of a tick-borne infection known as relapsing fever, caused by the bacteria Borrelia hermsii.
The response is so strikingly similar that it gives good reason for researchers to apply the strategy to a host of other infections to better understand how the immune system attempts to fights them— which could ultimately lead to precise treatment and prevention strategies.
“This is first time an interaction of an infectious agent with a host, the progression of the disease and its eventual resolution recapitulates what you would see in a human being,” said Kishore R. Alugupalli, Ph.D., Assistant Professor of Microbiology and Immunology at Thomas Jefferson University and the Kimmel Cancer Center at Jefferson. “Our model is not only a susceptible model, but it actually tells us how the human immune system is functionally working. That is the big difference from the previous studies.”
What really surprised the team is that the mouse physiological environment was able to facilitate the development of human B1-like cells, which is specialized type of antibody producing systems used to fight infection due to a variety of bacterial pathogens, including Pneumococcus and Salmonella.
In the study, researchers transferred hematopoietic stem cells from human umbilical cord blood into mice lacking their own immune system. This resulted in development of a human immune system in these mice. These “human immune system” (HIS) mice were then infected to gauge response.
According to the authors, an analysis of spleens and lymph nodes revealed that the mice developed a population of B1b-like cells that may have fought off the infection. Researchers also observed that reduction of those B cells resulted in recurrent episodes of bacteremia, the hallmark of relapsing fever.
“The B1b cells in humans had been speculated, but never confirmed,” said co-author Timothy L. Manser, Ph.D., Professor and Chair of the Department of Microbiology and Immunology at Jefferson. “We found that in mice, the B1b cell subset is critically important for resolution of this type of bacterial infection.”
“This would indicate that there is a functional equivalent of the subset in humans that has not been previously recognized,” he added.
The mouse model with relapsing fever recapitulates many of the clinical manifestations of the disease and has previously revealed that T cell-independent antibody responses are required to resolve the bacteria episodes. However, it was not clear whether such protective humoral responses are mounted in humans.
“It’s an amazing platform that could be used to really study how the human B1 cells could work against a variety of bacterial and viral infections,” said Dr. Alugupalli.
Steve Graff | Newswise Science News
Two Group A Streptococcus genes linked to 'flesh-eating' bacterial infections
25.09.2017 | University of Maryland
Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden
At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.
Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
25.09.2017 | Trade Fair News
25.09.2017 | Physics and Astronomy
25.09.2017 | Life Sciences