PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

These dendritic cells are fishy, but that's a good thing

2010-09-08
(Press-News.org) Scientists from the University of California, San Diego School of Medicine have identified dendritic antigen-presenting cells in zebrafish, opening the possibility that the tiny fish could become a new model for studying the complexities of the human immune system.

The study, reported in the online edition of the Proceedings of the National Academy of Sciences, was headed by David Traver, an associate professor in UCSD's Department of Cellular and Molecular Medicine, with colleagues in UCSD's Division of Biological Sciences and at the Brazilian National Cancer Institute.

Dendritic cells (DCs) form a crucial link between the innate and adaptive immune systems in mammals. Innate immunity is present in all organisms, providing immediate but short-lived and relatively non-specific defense against infection. Adaptive immunity is evolutionarily younger and more complex. It produces long-lasting protection against specific pathogens after initial exposure. Mammalian DCs act as sentries that bridge the innate and adaptive systems, confronting and engulfing newly discovered pathogens, then recruiting and activating antigen-specific T lymphocytes.

While DCs and the adaptive response have been well-documented in mammals, it was not clear whether these cells existed in non-mammalian vertebrates. Scientists knew that zebrafish – an increasingly popular animal model – exhibited many of the cellular elements of the adaptive system, including T and B lymphocytes, but no one had documented the presence of dendritic cells.

Traver and colleagues inventoried hematopoietic cells that could engulf labeled bacteria, looking for cells that appeared and behaved like mammalian DCs. They found multiple suspects, but finally zeroed in on one rare cell type that appears to fit all of the criteria for being a dendritic cell.

"All signs point to these cells being the fish version of dendritic cells," said Traver. "They have all of the major characteristics."

The discovery of DCs in zebrafish provides researchers with another model for investigating the mammalian immune system, particular with regard to humans. "The cool thing is that the more we learn, the more we realize that our immune systems are highly conserved," said Traver. "Of course, there are differences. These differences, however, are variations on a theme, with the major themes of immune cell function being quite similar. Likewise, there are differences and variations in the dendritic cells of mice compared to humans, but the basics are the same."

Zebrafish do offer some practical research advantages over other models.

First, the fish are translucent. "You can track individual cells and systems directly in the whole animal," said Traver. "Very little is known about the initial immune response in mammals because we can't see it happening. In these fish, we can visualize what happens in real time."

Second, zebrafish are easy to handle and reproduce rapidly, making it easier to engineer and study mutations. "We can quickly grow generations of fish, letting the genetics tell us what's important," Traver said.

###

Co-authors with Traver are Geanncarlo Lugo-Villarino, Keir M. Balla and David L. Stachura of the Section of Cell and Developmental Biology, Division of Biological Sciences, UC San Diego and Miriam B.F. Werneck of the Division of Cellular Biology, Brazilian National Cancer Institute.

END



ELSE PRESS RELEASES FROM THIS DATE:

A better way to treat HIV-infected children?

2010-09-08
September 7, 2010 (4 pm ET) – Nevirapine is widely used to help prevent mother-to-child transmission of the HIV virus. In cases where the infants are nonetheless infected with HIV virus at birth, the standard treatment is to use protease inhibitors (PI) to reduce the amount of virus in their bloodstream. A new study involving 195 infants in South Africa found that children who were treated with PI and then switched to nevirapine were more likely to maintain virus below the detection threshold of the test than infants who continued to receive PI. Results of the study are ...

Harmful amyloid interferes with trash pickup for cells in Alzheimer's disease

Harmful amyloid interferes with trash pickup for cells in Alzheimers disease
2010-09-08
Chemists at the University of California, San Diego, have identified how a protein that accumulates in the brains of people with Alzheimer's disease interferes with the ability of cells to get rid of debris. They also found a natural mechanism by which this protein, amyloid beta, itself may be discarded. Plaques of amyloid are a hallmark of the ailment, but no one is sure exactly how they contribute to catastrophic loss of memory and cognition. Scientists have begun to suspect that amyloid disables a structure called a proteasome, which chops up proteins that cells ...

Young, male, testosterone-fueled CEOs more likely to start or drop deals: UBC study

2010-09-08
Too much testosterone can be a deal breaker, according to Sauder School of Business researchers at the University of British Columbia. Their paper, to be published in the INFORMS journal Management Science on September 10, shows that young CEOs with more of the steroidal hormone in their system are more likely to initiate, scrap or resist mergers and acquisitions. The study by Sauder Finance Professors Maurice Levi and Kai Li, and PhD student Feng Zhang, titled "Deal or No Deal: Hormones and the Mergers and Acquisitions Game," shows that testosterone – a hormone associated ...

Study examines turbine effects on Yukon River fish

2010-09-08
Fairbanks, Alaska—A University of Alaska Fairbanks fisheries scientist has teamed up with Alaska Power and Telephone to study how a new power-generating turbine affects fish in the Yukon River. So far, the news looks good for the fish. "In the brief testing that we have been able to accomplish, we have no indication that the turbine has killed or even injured any fish," said Andrew Seitz, project leader and assistant professor of fisheries. Alaska Power and Telephone installed the in-stream turbine near Eagle, Alaska this summer. They are testing its effectiveness ...

Research on team loyalty yields new insight into 'die-hard' fandom

Research on team loyalty yields new insight into die-hard fandom
2010-09-08
CHAMPAIGN, Ill. – There's a reason why some sports fans are referred to as "die-hards" – even after they move away, their loyalty to their hometown team endures, according to research by two University of Illinois professors. Scott Tainsky and Monika Stodolska, professors of recreation, sport and tourism, say new residents of a community maintain an attachment to their old team or former city as a way of asserting their identity after they move. "People new to a city don't just adopt their new hometown's team as a way to acclimate themselves in a new community," Tainsky ...

No need to worrry about deflation -- yet, U. of I. economist says

No need to worrry about deflation -- yet,  U. of I. economist says
2010-09-08
CHAMPAIGN, Ill. — A University of Illinois economist says consumers and investors concerned about the specter of deflation looming over an already bleak economic landscape should relax – for the time being, at least. Although the consumer price index is near zero, J. Fred Giertz says we're unlikely to see a prolonged deflationary period like the slump Japan experienced during its "lost decade" of the 1990s. "We're close to zero right now, but we're not below zero," said Giertz, an Institute of Government and Public Affairs economist who compiles a monthly barometer ...

Brown-led research divines structure for class of proteins

Brown-led research divines structure for class of proteins
2010-09-08
PROVIDENCE, R.I. [Brown University] — Most proteins are shapely. But about one-third of them lack a definitive form, at least that scientists can readily observe. These intrinsically disordered proteins (IDPs) perform a host of important biological functions, from muscle contraction to other neuronal actions. Yet despite their importance, "We don't know much about them," said Wolfgang Peti, associate professor of medical science and chemistry. "No one really worried about them." Now, Peti, joined by researchers at the University of Toronto and at Brookhaven National Laboratory ...

New compound safely reduces plaques in mouse model of Alzheimer's disease

2010-09-08
A new study identifies molecules that can be used to selectively reduce generation of the sticky, neuron-damaging plaques that are the hallmark of the Alzheimer's disease (AD) brain. The research, published by Cell Press in the September 9 issue of the journal Neuron, may lead to the development of effective and safe therapeutics for this currently incurable disease. Previous research has suggested that an alteration in brain levels of amyloid ? proteins (A?) plays a major pathogenic role in AD, a devastating neurodegenerative disorder that causes progressive cognitive ...

Brain mechanism linked to relapse after cocaine withdrawal

2010-09-08
Addictive drugs are known to induce changes in the brain's reward circuits that may underlie drug craving and relapse after long periods of abstinence. Now, new research, published by Cell Press in the September 9 issue of the journal Neuron, uncovers a specific neural mechanism that may be linked to persistent drug-seeking behavior and could help to guide strategies for development of new therapies for cocaine addiction. Previous research has shown that the ventral tegmental area (VTA) is a brain region that is activated when cocaine users experience a craving for cocaine ...

Single gene regulates motor neurons in spinal cord

Single gene regulates motor neurons in spinal cord
2010-09-08
New York (September 8, 2010) – In a surprising and unexpected discovery, scientists at NYU Langone Medical Center have found that a single type of gene acts as a master organizer of motor neurons in the spinal cord. The finding, published in the September 9, 2010 issue of Neuron, could help scientists develop new treatments for diseases such as Lou Gehrig's disease or spinal cord injury. The "master organizer" is a member of the Hox family of genes, best known for controlling the overall pattern of body development. By orchestrating a cascade of gene expression in ...

LAST 30 PRESS RELEASES:

Can early exposure to dogs lessen genetic susceptibility to eczema?

Are stress and resilience factors among gender and sexual minority adolescents related to sleep health?

How does a common plant pathogen affect urban trees, and how should it be managed?

Which seeds are best to include in annual flowering seed mixes to attract insect pollinators?

How useful are states’ adolescent social media laws?

Evidence to support state policies regulating teen use of social media is limited, study finds

Pet dogs could combat genetic eczema risk in children

A threesome that hatches potato parasites

Young people discover the technologies shaping their future in the World Economic Forum and Frontiers for Young Minds collection

Real-time 3D visualization reveals potent antibacterial and antibiofilm activity against superbacteria

Abnormal uterine bleeding and insulin resistance are on the rise: Is there a connection?

Eye wear breakthrough: MXene-coated lenses for safer and smarter wearables

‘AI scientist’ suggests combinations of widely available non-cancer drugs can kill cancer cells

Phage therapy at a turning point: Global experts converge in Berlin to shape the future of antimicrobial medicine

Low calorie diets linked to heightened risk of depressive symptoms

Bronchiolitis, monoclonal antibody halves hospitalizations of children younger than six months old

Mum’s obesity linked to child’s heightened hospital admission risk for infection

Millions of new solar system objects to be found and ‘filmed in technicolor’ – studies predict

Pitt study has upended decades-old assumptions about brain plasticity

Hertz Foundation partners with Analog Devices to empower future leaders in analog, digital and software technology solutions

Would you hand over your health data if it meant better care?

Study examines how well wearable tech tracks fitness metrics

Dr. Nikolaos Koundouros wins 2025 Tri-Institutional Breakout Award

Low vs. High blood pressure avoidance in non-cardiac surgery: Neurocognitive outcomes unchanged

Telehealth can improve care for cats with chronic health issues

Researchers develop innovative model to study sense of smell

Birds may be drinking on the wing, but in moderation

Collaboration can unlock Australia’s energy transition without sacrificing natural capital

Study identifies proteins involved in the effectiveness of immunotherapy against blood cancer

Cannabis extract could treat fungal diseases

[Press-News.org] These dendritic cells are fishy, but that's a good thing