A discovery by Australian immunologists uncovered an additional role for antibody-making ‘B cells.’ The finding shows that B cells also participate in the development of ‘regulatory T cells.’ Until now, the only non-thymic cells known to educate the regulators were dendritic cells, which travel to the thymus to deliver ‘antigen’, samples of substances toxic to the body. We now know that B cells can do the same thing.
The ability of microorganisms to overcome antibiotic treatments is one of the top concerns of modern medicine. The effectiveness of many antibiotics has been reduced by bacteria's ability to rapidly evolve and develop strategies to resist antibiotics. Bacteria achieve this by specific mechanisms that are tailored to the molecular structure or function of a particular antibiotic.
Signals from the immune system that help repel a common parasite inadvertently can cause a dormant viral infection to become active again, a new study shows. Further research is necessary to understand the clinical significance of the finding, but researchers said the study helps illustrate how complex interactions between infectious agents and the immune system have the potential to affect illness.
An international research team has solved the mystery of how birds avoid Lassa virus infection, leading to a better understanding of how Lassa virus infects mammals.
Chronic hepatitis C virus infections are among the most common reasons for liver transplants. Because existing viruses also infect the new liver, the immune system is highly active there. Despite this, the new organ is not rejected. The long-term stimulation of the innate immune system by the virus actually increases the probability of tolerance.
Bone marrow transplants save thousands of lives but patients are vulnerable to severe viral infections in the months afterward. Now, scientists are developing protection for that risky period — injections of cells specially designed to fend off up to five different viruses at once.
As many patients know, treating wounds has become far more sophisticated than sewing stitches and applying gauze, but dressings still have shortcomings. Now scientists are reporting the next step in the evolution of wound treatment with a material that leads to faster healing than existing commercial dressings and prevents potentially harmful bacteria from sticking.
The immune system includes natural killer cells (NK cells), which recognize and eliminate tumor or virus-infected cells. NK cells combat the body’s own stressed cells to prevent them from becoming a potential hazard. However, this bears its risks.
Responding to a major case of research misconduct, federal prosecutors have taken the rare step of filing charges against a scientist after he admitted falsifying data that led to millions in grants and hopes of a breakthrough in AIDS vaccine research.
Biologists have long wondered if mammals share the elegant system used by insects, bacteria and other invertebrates to defend against viral infection. Two back-to-back studies in the journal Science last year said the answer is yes, but a study just published in Cell Reports by researchers at the Icahn School of Medicine at Mount Sinai found the opposite.
People who get bitten by a blacklegged tick have a higher-than-expected chance of being exposed to more than one pathogen at the same time. Research found that almost 30 percent of the ticks were infected with the agent of Lyme disease. One-third of these were also infected with at least one other pathogen. The agents of Lyme disease and babesiosis were found together in 7 percent of ticks.
Researchers have discovered how a protein molecule in immune cells promotes the production of nitric oxide, a potent weapon in the cells’ arsenal to defend the body from bacterial attack. The protein may offer a target for reining in the inflammatory response, which must be able to fight infection without damaging tissue.
Computer simulations that reveal a key mechanism in the replication process of influenza A may help defend against future deadly pandemics. Treating influenza relies on drugs, such as Amantadine, that are becoming less effective due to viral evolution. But University of Chicago scientists have published computational results that may give drug designers the insight they need to develop the next generation of effective influenza treatment.
Bacteria that cause ulcers in humans undergo accelerated evolution during the initial stages of infection, allowing them to evade the immune system, according to new research. The study shows, for the first time, and in real-time, the interplay between the human immune system and invading bacteria that allows the bacteria to counter the immune response by quickly evolving.
Biologists discovered new mechanisms used by bacteria to manufacture lipids, i.e. fat molecules, for the cell membrane. Those mechanisms are a combination of familiar bacterial synthesis pathways and of such that occur in higher organisms. Thus, the team has debunked the long-standing theory that lipid production in bacteria differs substantially from that in higher organisms.
A provocative new study links prolonged episodes of sepsis— a life-threatening infection and leading cause of death in hospitals— to the reactivation of otherwise dormant viruses in the body.
The immune system maintains a rich abundance of “natural killer” cells to confront microbial invaders, but as the body gains the upper hand in various infections, it sometimes starts to produce even more of the cells. For three decades, scientists haven’t understood what purpose that serves. In a new paper, researchers show one: proliferation helps change the NK cells’ function from stimulating the immune response to calming it down.
The human body is comprised of roughly 10 times more bacterial cells than human cells. In healthy people, these bacteria are typically harmless and often helpful, keeping disease-causing microbes at bay. But, when disturbances knock these bacterial populations out of balance, illnesses can arise. Periodontitis, a severe form of gum disease, is one example.
Scientists have tested a new genetic method that distorts the sex ratio of Anopheles gambiae mosquitoes, the main transmitters of the malaria parasite, so that the female mosquitoes that bite and pass the disease to humans are no longer produced.
Researchers identified the evolutionary origins of human herpes simplex virus (HSV) -1 and -2, reporting that the former infected hominids before their evolutionary split from chimpanzees 6 million years ago while the latter jumped from ancient chimpanzees to ancestors of modern humans – Homo erectus – approximately 1.6 million years ago.
A team from Duke and the University of Sydney in Australia has solved the structure of a key protein that drives DNA copying in the plasmids that make staphylococcus bacteria antibiotic-resistant. Knowing how this protein works may now help researchers devise new ways to stop the plasmids from spreading antibiotic resistance in staph by preventing the plasmids from copying themselves.
Cytomegalovirus, or CMV, is perhaps one of the biggest pathogens you’ve never heard of—big, both proportionately and epidemiologically. If you’re healthy, it’s harmless, but if you have an impaired immune system, the virus can assert itself with a vengeance. Now, researchers have discovered a menu of tactical secrets CMV employs.
A new report offers the strongest evidence yet that a mysterious Middle East virus spreads from camels to people. Researchers studied the illness of a 44-year-old camel owner in Saudi Arabia, who died in November of Middle East respiratory syndrome, or MERS.
A Purdue University-led research team has figured out how to disable a part of the SARS virus responsible for hiding it from the immune system; a critical step in developing a vaccine against the deadly disease. The findings also have potential applications in the creation of vaccines against other coronaviruses, including MERS.
By analyzing the blood of almost 100 treated and untreated HIV-infected volunteers, a team of scientists has identified previously unknown characteristics of B cells in the context of HIV infection.