RELATIVE RESOURCE MANAGER

Relative Resource Manager

Relative Resource Manager

Question 1:

Cytokines are immune system proteins that modulate or influence the immune response. Cytokines are produced when the immune system encounters an immune stimulus. Once induced, cytokines help determine how the immune system should respond and to what degree.

Cytokines are produced by various immune system white blood cells, and they're categorized by their major function: for instance cytokines may be pro-inflammatory compounds, anti-inflammatory compounds, or growth factors. Cytokines may also induce the production of effector molecules or various cell receptors, and they may cause the proliferation of various immune system cells that are needed to prolong the immune response.

Subtypes

Cytokines are a general class of proteins that are often referred to by their specific function or by the cells that produced them.

Monokines--Cytokines produced by monocytes

Lymphokines—Cytokines produced by lymphocytes

Chemokines—Cytokines with chemotactic activities

Interleukins—Cytokines made by certain leukocytes and acting on others

Interferons—Cytokines that influence the function of immune system cells

Cytokine Activities

Cytokines contribute to the symptoms of autoimmune disorders by releasing toxic chemicals and damaging cells. In rheumatoid arthritis and other rheumatic disorders, cytokines contribute to joint destruction and synovitis. Cytokines, depending on their type and function, can also trigger and perpetuate inflammation and they can taper the immune system's response, helping disease flares resolve.

Cytokines act by binding to specific receptors or locks on cell surfaces. Cytokines can act on specific cells or they can have the property of pleiotropy, which allows them to react with various cell types. Cytokines can work together or synergistically or they can work antagonistically, working to reduce the activity of other cytokines.

Question 2:

A novel polyomavirus (WU virus) has been identified in pediatric patients with acute respiratory tract infections (ARI), but its role as a respiratory pathogen has not yet been demonstrated. Clinicians can typically use a patient's symptoms to determine that a virus is the likely culprit in a respiratory infection. However, even with advanced testing they still can't pin the blame on a particular virus in roughly one-third of all such infections.

Scientists can't yet prove that the new virus, known as the WU virus, is making patients sick. But senior author David Wang, Ph.D., of Washington University School of Medicine in St. Louis, is suspicious enough that he's started follow-up studies.

In patients with immune deficiencies, polyoma viruses can pose serious health threats. For example, one of the most infamous polyoma viruses, the JC virus, is a leading secondary infection in HIV patients. It causes a life-threatening neurological disorder called progressive multifocal leukoencephalopathy.

Question 3:

Influenza viruses are negative-sense RNA viruses with a segmented genome that replicate in the nucleus of infected cells. They are common pathogens of humans and a wide variety of animal species, causing significant morbidity and mortality. There are three groups of Influenza viruses, called influenza A, B and C, with influenza viruses A and B being similar in structure and biological properties and influenza virus C having different proteins responsible for binding and entry into target cells.

Entry into a host cell is of fundamental importance in infection and pathogenesis ...