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
Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University
How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung
Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.
Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
26.05.2017 | Life Sciences
26.05.2017 | Life Sciences
26.05.2017 | Physics and Astronomy