lb+immune+SAC

One of the criteria for the immune response SAC requires you to show your progress in developing your presentation. On this page you should have the following. You should show your planning of the presentation, such as the images chosen and information you want to convey. This includes how you broke up your topic into the various sections. You should also include why you sequenced the images the way you did and the collating of information. It is important that you acknowledge any sources of information (including images) below. You will also need to upload your audio file onto this page.

So i've decided to focuse on the Humoral repsonse, partially because no one else is focussing on it, but partially because i am still a little unfamiliar with the specifics. Here is my speech, with info i've gathered from the sites below.

My order goes as follows: 1.Intro to humoral 2.B cells (fundamental to immune response, so important to mention early) 3.B cell's release antibodies 4.Antibody interaction with antigen. (incl. epitope), relate back to T cells and immune system to put back into context for audience 5.Thus, effect of T cells on B cells (incl. plasma and memory B cell formation) 6.Antibody structure (comes after B cells because of close relationship and relevance) 7.How antibody functioning ties in with medicine; vaccine 8.Summary of process; important to tie up all info mentioned in slide, and to demonstrate clearer and more direct understanding of content. <-- humour Hello and welcome to my podcast. Today, I’ll be speaking to you about the humoral response. The humoral system involves an immune response carried out by B cells and antibodies. This system is also identified as the **antibody-mediated system**, because of its specific immune-system structures known as //antibodies//. But we’ll be discussing these later on. The humoral response deals with infectious agents in the blood and body tissues, and is managed by B-cells. (With the help from T-cells of course) It is a form of specific immunity, as it distinguishes between self and non-self, and involves cells and proteins that attach to foreign bodies. Furthermore the level of response is greater and faster for secondary infection by the same organism. It is a third line of defence and involves lymphocytes, which you may remember are white blood cells. Both the humoral and cell-mediated systems exhibit a //fascinating// interrelationship that allows them to protect the body against almost any antigen. Now, you may be wondering, I understand the basics of the humoral response. But //how// does it go about fighting these problems? Well, that’s where I come in. First thing you need to understand, are the B cells.

**__<-- humour, more interesting__**

The way I like to see it, is that B cells are very similar to a typical housewife. She is neither violent, nor destructive. Yet she regulates the household, ensuring the functioning of her family is at its optimum. __**<-- clear, simple, reflects communication between specific antigen presenting cell and antibody-binding sitein**__

Similarly, B cells neutralise foreign material, yet do not kill the pathogen. They are a type of lymphocyte that assists in the humoral immune response. They release antibodies that control the actions of an antigen. Every antibody has at least 2 antigen binding sites, specific to a small area of an antigen. //Specific//. This is the key in understanding the interaction of an antigen with an antibody. This specific area of the antigen is known as the epitope. __**<-- more specific than previous diagram, shoes relationship b/w epitope, antigen and antibody**__

Still with me? Well, with the assistance of an antibody, these epitopes can clump together in some way or another, to make antigens more identifiable for macrophages. Understanding the names of these actions is not essential, but note that the binding of antibodies to the surface of pathogens can also activate compliment proteins, which cause the cell to lyse,

__**<-- provides a visual example of an antibody function**__

The following diagram demonstrates antibodies agglutinating the antigens together in large groups, that can subsequently be removed by other components of the immune system (such as the complement system, macrophages or T cells) When a T lymphocyte "sees" the same peptide on the macrophage and on the B cell, the T cell stimulates the B cell to turn on antibody production. So with its interaction with an epitope, B cells release cytokines that summon T helper cells. These T helper cells then activate the b cells to undergo repeated cell division, enlargement and differentiation in order to form a clone of plasma and memory B cells.

__**<-- humour**__

But hold on. What //are// plasma and memory b cells?

__**<-- illustrates the differentiation and division of B cells, including the difference between plasma and memory cells**__

Well, Plasma b cells produce the specific antibodies that provide makers for phagocytes to essentially come along and engulf the foreign material. They eventually die off after a few days. Memory B cells, on the other hand, stay in the body for pretty much the rest of your life, even after the pathogen has been eliminated, circulating in the lymphatic tissue. Upon a secondary infection, they have a head start, with more antibodies already produced to fight back faster and more rapidly. So the next thing I want to ask you, is what do you know about antibodies? Do you know that they are also referred to as immunoglobulins, and that they are large glycoproteins? Or perhaps that they prevent pathogens from harming us without directly //destroying// the pathogen. Well I’m here to tell you remind you of these things and more. Antibodies circulate in the blood and lymph tissue, developing in bone marrow. An easy way to remember this is think B for bone marrow, and B for B cells.

 __**<-- good, simple diagram, shoes variable and constant region, along with antigen binding sides, and light/heavy chain**__

The structure of each immunoglobulin differs according to its specific function, but ultimately all antibodies have the same basic units. As you can see in this diagram, antibodies are Y shaped, and are formed by the variable region at the top of the antibody molecule (or the light blue area). Yet note that the majority of the antibody is known as the constant region, and is highlighted in dark blue. Antibodies have two identical arms that bind to two antigen molecules, and are known as the antigen-binding site, and, as we discussed earlier, attach to epitopes. Each antibody has 4 chain structures, composed of two identical light chains, and two identical heavy chains. Ok so, now the question remains; why do we need to know how the humoral response works? The answer, of course, is medicine. Antibodies play an essential role in vaccinations.

__**<-- provides audience with visual imagery that relates theory of humerol system/vaccines to human body (ie something more familiar) as oppose to showing how vaccines work at a cellular level**__  As you can see here, a vaccine is injected into the blood stream, containing a weakened or inactive virus. Vaccines can be produced by either killing the virus with a chemical, thus sustaining only its antigens, by reducing its strength of the virus, and therefore its ability to efficiently reproduce once inside the body, or by completely removing the harmful parts of the virus. However, the vaccine will always display non-self antigens. As you now know, this non-self material will elicit an immune response, partially by the humoral system. The B cells in the blood stream produce antibodies in response to the antigen. Simultaneously, memory cells are produced, which remain, as we said, in the body for many years.

__**<-- humour, breaks up talk**__  Thus upon any subsequent infections from the same pathogen, the body will treat the virus as a secondary infection, as it has already been exposed to the virus and established memory cells, resulting in a more rapid, greater response. This biomedicine is known as artificial passive immunity, as there is an external input (meaning the vaccine) that stimulates the body to carry out a response. So just to recap;

__**<-- perfect summary of talk, my speech also coincided with this diagram the most.**__

When we are invaded by a virus, macrophages come along, engulf the non-self matter through phagocytosis. Then these macrophages digest the infectious agents, displaying its antigens on their surface. After that the helper T cells recognize this and activate immune response, multiplying rapidly. This phase is known as the activation stage. Now for the effector phase. This is where, as we discussed earlier, T helper cells activate B cells to multiply rapidly to produce more antibodies (which differentiate into either plasma or memory b cells) The plasma cells manufactures large quantities of antibodies to fight the pathogen by binding to the antigen and preparing it for destruction. And don’t forget, the b memory cells remember the specific antigen, so that they can be used to mobilize the immune system faster upon a secondary infection.

Questions http://www.biology.arizona.edu/immunology/tutorials/immunology/05q.html

Link to video http://www.montereyinstitute.org/courses/AP Biology II/course files/multimedia/lesson46/lessonp.html?showTopic=4

Antibody structure http://www.biology.arizona.edu/immunology/tutorials/antibody/structure.html

Immunology http://www.biology.arizona.edu/immunology/immunology.html

Macromolecules http://www.rcsb.org/pdb/home/home.do

Online biolgy book http://www.estrellamountain.edu/faculty/farabee/biobk/biobooktoc.html (Immunity) http://www.estrellamountain.edu/faculty/farabee/biobk/BioBookIMMUN.html

Pictures: http://en.wikipedia.org/wiki/Antibody http://cancerres.aacrjournals.org/cgi/content/abstract/68/13/5405 http://www.biology.arizona.edu/immunology/tutorials/immunology/humoral.html http://en.wikipedia.org/wiki/Humoral_immunity http://pathmicro.med.sc.edu/mayer/IgStruct2000.htm http://accessexcellence.org/AE/AEC/CC/images/making_vaccines.gif