 |
|
Scientists Develop Method to Track Immune System Enzyme in Live Animals
May 18, 2007Scientists supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) at the National Institutes of Health have created two mouse strains that will permit researchers to trace, in a live animal, the activity of an enzyme believed to play a crucial role both in the normal immune response as well as autoimmunity and B cell tumor development. Their report appears in the Journal of Experimental Medicine.
The enzyme, known as activation-induced cytidine deaminase or AID (which has no relation to the AIDS virus), is expressed by B cells, which are produced in the bone marrow and are responsible for making antibodies that attack foreign invaders such as viruses and bacteria. The enzyme enables the cells to respond with precision to the almost limitless types of invaders the body may encounter. Unfortunately, it also has a down side.
B cells constantly scan the body for foreign invaders, explains Rafael Casellas, Ph.D., an investigator in NIAMS' Molecular Immunology and Inflammation Branch and lead author of the paper. As B cells encounter foreign antigens from viruses, bacteria or allergens, they migrate to germinal centers - specialized microenvironments in tonsils, spleen and lymph nodes. Within germinal centers, B cells divide extensively and express the AID enzyme, which causes random mutations and recombination in the cells' immunoglobulin (antibody) genes. For the most part, these genetic changes are beneficial because they enable B lymphocytes to attack and stop the invader. In some cases, however, AID-dependent alterations in the genetic material of B cells can also lead to unwanted results such as autoimmunity and development of B cell tumors, as in the case of Burkitt lymphoma.
"It becomes crucial that we comprehend how AID is regulated during the normal immune response as well as in tumorigenesis and autoimmunity," says Casellas. The problem with understanding how AID is regulated or deregulated is that there has not been an easy way to visualize the enzyme's action in a living animal - until now.
To address this issue, Dr. Casellas and his colleagues created transgenic mice that had a green fluorescent protein derived from jellyfish fused to the AID enzyme. In these transgenic animals, B cells express the tagged enzyme during the immune response. In a second mouse strain, Casellas and coworkers expressed permanently a yellow fluorescent protein in the progeny of germinal center B cells. "Thanks to these new mouse models, we can track in live animals whenever the AID enzyme is active as well as the result of that activity," says Casellas. Scientists can also cross these new mouse strains with mice predisposed to B-cell tumors or autoimmunity to see differences in enzyme expression in health and disease.
NIAMS Director Stephen I. Katz. M.D., Ph.D., believes these new tools have great potential to help solve some mysteries of the immune system, such as the causes of B-cell tumors and autoimmunity. "The better we understand these problems," he says, "the closer we come to better treatments for them and eventually, perhaps, ways to prevent them."
The National Institutes of Health (NIH)
"It becomes crucial that we comprehend how AID is regulated during the normal immune response as well as in tumorigenesis and autoimmunity," says Casellas. The problem with understanding how AID is regulated or deregulated is that there has not been an easy way to visualize the enzyme's action in a living animal - until now.
To address this issue, Dr. Casellas and his colleagues created transgenic mice that had a green fluorescent protein derived from jellyfish fused to the AID enzyme. In these transgenic animals, B cells express the tagged enzyme during the immune response. In a second mouse strain, Casellas and coworkers expressed permanently a yellow fluorescent protein in the progeny of germinal center B cells. "Thanks to these new mouse models, we can track in live animals whenever the AID enzyme is active as well as the result of that activity," says Casellas. Scientists can also cross these new mouse strains with mice predisposed to B-cell tumors or autoimmunity to see differences in enzyme expression in health and disease.
NIAMS Director Stephen I. Katz. M.D., Ph.D., believes these new tools have great potential to help solve some mysteries of the immune system, such as the causes of B-cell tumors and autoimmunity. "The better we understand these problems," he says, "the closer we come to better treatments for them and eventually, perhaps, ways to prevent them."
The National Institutes of Health (NIH)
Immune Response Current Events and Immune Response News RSSNew Notre Dame study provides insights into the molecular basis of tumor cell behavior
A new study by a team of researchers led by Crislyn D'Souza-Schorey, associate professor of biological sciences at the University of Notre Dame, sheds light on the molecular basis by which tumor cells modulate their surroundings to favor cancer progression.
New Synthetic Molecules Trigger Immune Response to HIV and Prostate Cancer
Researchers at Yale University have developed synthetic molecules capable of enhancing the body's immune response to HIV and HIV-infected cells, as well as to prostate cancer cells. Their findings, published online in the Journal of the American Chemical Society, could lead to novel therapeutic approaches for these diseases.
Common Pain Relievers May Dilute Power of Flu Shots
With flu vaccination season in full swing, research from the University of Rochester Medical Center cautions that use of many common pain killers - Advil, Tylenol, aspirin - at the time of injection may blunt the effect of the shot and have a negative effect on the immune system.
PATH Malaria Vaccine Initiative shares strategy for developing 'next-generation' malaria vaccines
Marking its tenth anniversary year, the PATH Malaria Vaccine Initiative (MVI) today unveiled a new strategy that sets the stage for an aggressive push targeting the long-term goal of eliminating and eradicating malaria. Malaria is one of the world's deadliest infectious diseases, killing nearly 900,000 people a year, most of them children in sub-Saharan Africa.
Study reveals a 'missing link' in immune response to disease
The immune system's T cells have the unique responsibilities of being both jury and executioner. They examine other cells for signs of disease, including cancers or infections, and, if such evidence is found, rid them from the body. Precisely how T cells shift so swiftly from one role to another, however, has been a mystery.
Initial Results Show Pregnant Women Mount Strong Immune Response To One Dose of 2009 H1N1 Flu Vaccine
Healthy pregnant women mount a robust immune response following just one dose of 2009 H1N1 influenza vaccine, according to initial results from an ongoing clinical trial sponsored by the National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health.
Progress made on group B streptococcus vaccine
Scientists supported by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, have completed a Phase II clinical study that indicates a vaccine to prevent Group B Streptococcus (GBS) infection is possible.
Bacteria 'launch a shield' to resist attack
Researchers from the University of Copenhagen and the Technical University of Denmark along with other collaborators in Denmark and the US found that the bacterium Pseudomonas aeruginosa can 'switch on' production of molecules that kill white blood cells - preventing the bacteria being eliminated by the body's immune system.
Scientists use world's fastest supercomputer to create the largest HIV evolutionary tree
Supporting Los Alamos National Laboratory's role in the international Center for HIV/AIDS Vaccine Immunology (CHAVI) consortium, researchers are using the Roadrunner supercomputer to analyze vast quantities of genetic sequences from HIV infected people in the hope of zeroing in on possible vaccine target areas.
Study shows how carbon nanotubes can affect lining of the lungs
Carbon nanotubes are being considered for use in everything from sports equipment to medical applications, but a great deal remains unknown about whether these materials cause respiratory or other health problems.
More Immune Response Current Events and Immune Response News Articles
 |
Immune Response and the Eye (Chemical Immunology) by Jerry Y. Niederkorn (Editor), Henry J. Kaplan (Editor) In memory of J. Wayne Streilein, the pioneer in ocular immunology The second edition of Immune >Response and the Eye' highlights recent insights into the >dangerous compromise' between the immune system and the eye, which protects the eye against pathogens while limiting inflammation and immune-mediated injury to ocular tissues with little or no regenerative potential. It discusses the broad spectrum of physiological, immunological, anatomical, and biochemical adaptations that conspire to closely regulate the tone and tenor of immune responses in the eye. This volume further describes immune-mediated diseases that occur when the compromise between the immune system and the eye is breached. This breakdown in immune privilege threatens the vision of millions each year. Finally, recent... |
 |
Understanding Hereditary Angioedema: A Mysterious Out-of-Control Immune Response Part of the award winning public television series Healthy Body/Healthy Mind. Its called Hereditary Angioedema and its so rare popular television shows have used it as one of their mystery diagnoses. But for the people who suffer with this condition the drama associated with an episode of hereditary angioedema is anything but entertaining. It can be harrowing and horrifying because a person's face or knees or other parts of the body that once looked normal suddenly takes on grotesque proportions due to an unusual amount of swelling. This condition baffled scientists and researchers for many years but today there are new treatments for hereditary angioedema that are helping people with this condition live healthy normal lives. In this program we'll hear what the experts have discovered... |
 |
Antioxidant + Resveratrol , (60 Capltes/bottle) This product provides nutritional support to defend against the effects of free radicals. Resveratrol is a type of polyphenol called a phytoalexin. Resvertraol works by binding to a class of proteins called sirtuins, which regulate the enzymes that can stimulate cancer-cell growth and suppress immune response. Resveratrol may also have powerful and diverse effects on the heart and blood vessels. by Vitamore Free-radicals (also called oxidants) are highly unstable molecules that can damage cell membranes. This may start a process that leads to several chronic diseases and may be involved with many aspects of aging. Free radicals are produced in the body during normal cell metabolism, and may also be caused by other environmental and lifestyle factors such as stress, smoking, polution, etc. This product provides nutritional support to defend against the effects of free radicals using the antioxidant vitamins of C and E and the trace elements of Zinc and Selenium. The key ingredient is the flavonoid-rich Resveratrol. Resveratrol is a type of polyphenol called a phytoalexin. Resvertraol works by binding to a class of proteins called sirtuins, which regulate the enzymes that can stimulate... |
 |
Source Naturals Nk-3 Immune Capsules, With Vitamin C, 250mg, 30-Count Bottle by Source Naturals NK-3 IMMUNE with vitamin C supports numerous natural immune processes, activating the work of macrophages, T cells, B cells, and natural killer or NK cells, the body¿s ¿first line of defense.¿ It stimulates the production of the chemical messengers that activate the body¿s natural immune response and it also supports a healthy circulatory system. |
|
Understanding Hereditary Angioedema: A Mysterious Out-Of-Control Immune Response Directed By: Information Television Network | |
 |
Vetri-DMG Tablets for Dogs & Cats (90 Tabs) by vetri science Vetri-DMG Tablets for Dogs & Cats (90 Tabs) (Supports Performance and Immune System Function) Vetri DMG is recommended to help support proper immune response, cardiovascular and skin health, glucose metabolism and proper nerve and brain functions. |
 |
The Human Body: How We Fail, How We Heal - DVD - The Teaching Company by The Teaching Company Your body is a fortress under constant assault. Infectious diseases, parasites, environmental toxins, physical trauma, allergens, and natural disasters are some external enemies it faces. From the inside, it is threatened by occasional overzealous allergic, immune, and inflammatory responses, as well as by the cellular mutations that produce cancer. Fortunately, the body's defenses are remarkably successful, and most of the time we are unaware of the intense drama taking place within our cells and organs. The intriguing details of this drama make up the field of pathophysiologythe study of the disruptions in a normal body's functions that are caused by disease or injury. Medical students get an exhaustive introduction to this subject early in their training, and the best clinicians are... |
 |
Metabolic Maintenance L-Glutamine 500 mg 100 caps by Metabolic Maintenance L-Glutamine 500 mg 100 caps |
 |
Bedside Emergencies: Anaphylactic Shock (Volume 3) Also With: Concept Media (Primary Contributor) Describes the body's normal immune response and how it responds physiologically to allergens. Differentiates between anaphylactic and anaphylactoid reactions, describing signs and symptoms. Describes initial interventions to slow down or prevent reaction from becoming life-threatening, as well as more aggressive therapy for severe, progressive reactions. |
 |
Cellular Signaling and Innate Immune Responses to RNA Virus Infections by Allan R. Brasier (Editor), Adolfo García-Sastre (Editor) Infections with RNA viruses represent a significant cause of morbidity and mortality in vertebrates. This volume is written with the belief that a careful examination of the early host responses to these RNA virus infections, as well as of the mechanisms adopted by these viruses to evade early host antiviral responses, will provide a platform of knowledge on which we will be able to develop new and more effective methods for controlling the spread of RNA viruses or modifying their disease course. |
| © 2009 BrightSurf.com |