Scientists have long held the prevailing view that during HIV infection the depletion of T cells is the result of direct HIV virus–mediated killing. In the September 15 issue of the Journal of Clinical Investigation, Marc Hellerstein and colleagues at the University of California in Berkeley report that it is the chronic activation of the host immune system in response to HIV infection that primarily contributes to T cell loss.
A series of influential studies published in the mid-1990s described the rapid decay of viral load following administration of highly active antiretroviral therapy (HAART), and proposed that HIV infection was associated with a high rate of virus turnover and short lifespan of infected cells. This suggested that HIV infection of susceptible CD4+ T cells led to such high rates of cell death, that compensatory T cell proliferation was inadequate to maintain sufficient T cell numbers and therefore compromised the ability of the immune system to fight the virus.
This view was recently challenged by observations that not only were virus-infected cells dying, but a greater number of uninfected bystander T cells underwent programmed cell death that was not a direct result of HIV infection. Therefore, a new theory has been proposed in which high levels of T cell proliferation reflects a state of chronic immune activation following HIV infection as opposed to simple compensatory proliferation.
Staphylococcus aureus: A new mechanism involved in virulence and antibiotic resistance
23.03.2018 | Institut Pasteur
Scientists develop tiny tooth-mounted sensors that can track what you eat
22.03.2018 | Tufts University
Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.
The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
23.03.2018 | Event News
19.03.2018 | Event News
16.03.2018 | Event News
23.03.2018 | Materials Sciences
23.03.2018 | Agricultural and Forestry Science
23.03.2018 | Physics and Astronomy