describe the actions of B cells and T cells in an immune response?
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Cytotoxic  or killer T cells (CD8+) do their work by releasing lymphotoxins, which cause cell lysis. Helper T cells (CD4+) serve as managers, directing the immune response. They secrete chemicals called lymphokines that stimulate cytotoxic T cells and B cells to grow and divide, attract neutrophils, and enhance the ability of macrophages to engulf and destroy microbes. Suppressor T cells  inhibit the production of cytotoxic T cells once they are unneeded, lest they cause more damage than necessary. Memory T cells  are programmed to recognize and respond to a pathogen once it has invaded and been repelled.
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the main part of specific immune system is Tcell and Bcell...it's hard to explain in details but i try to sum up,when the antigen enters the bode Tcell works a APC and receives antigene parts by MHC on it,MHC stimulate the Tcell to produce IL and INF and these stimulate Bcells to produce specific antibodies against Ag...some of these antibodies destroy the Ag by stimulating the complements and other parts of immune system and some Bcells convert to memory cells for the next time
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1 ribosomes\n2 stimuli\n3 enzyme\n4 cytoplasm
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D is a specific response.\n\nSpecificity refers to a specific defense that is activated by a specific antigen and the immune response targets that particular antigen and no others.\n\nNonspecific defenses are the same, regardless of the type of invading agent.  They include physical barriers, phagocytic cells, immunological surveillance, interferons, complement proteins, inflammation, and fever.
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A few sites on immunology here
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Innate immunity - non-specific to a particular pathogen, macrophages important cells here.  Also involves inflammation and acute phase response\n\nAdaptive immunity - specific and has 'memory cells'. Involves humoral immunity and cell mediated responses.  Involves reactions to specific antigenic challenges.\n\nComparative immunity - signal transduction pathways used to invoke immunity that are similar across a wide range of organisms - vertebrates, insects and even plants!!!  Don't really know much about this found it in a book, see source below!!!
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ok,I try to make it clear,\nimagine an antigen is invading the body,it is going to be diagnosed and captured by innate immune system like Mq,Neu...they represent the antigen to TCR on Tcell,so Tcell become activated and produce cytokines,some of them are going to activate Bcell and makes Bcell to produce Antibodies,antibodies will join antigens and some protein in blood may join them and they all destroy the antigen.\n\nBone marrow is the most important source of Bcell in lifetime.the most important responsibility of Bcell is to produce Antibodies.Antibodies are the most important part of the immune system for the extracellular pathogenes like toxins.B acts as an APC specially in the secondary response.Bcell secretes IL1,6,12 and INF alpha and beta.B has a memory so it plays an important role in the secondary response to antigen.B has some markers such as CD1,5,9.10,14,19,20,21,23,25,32,35,38,40,45,55,59,80,86,126,85,81.\n\nthere are two kinds of B,\n1)B1cell : mostly in newly borns,bigger than the other one,mostly produce IgM and respoce to Ti Ag.it doesn't have memory.it's only 5% of all the Bcells.\n2)B2cell:in older people,95% of all Bs,response to TD antigens and have memory..\n\nsome clues about Abs:there are five class of them,\nIgA(1,2),IgD (it's Ag receptor on Bcell),IgE(role in Allergies),IgG(more than others ,in 4 froms,activate the complemets,role in ADCC,feed back inhibition of Bcells),IgM(antigene receptor on Bcell,activates complemetns)\n\nthat's it,hope it helps;)
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B CELLS ARE ANTI-BODY PRODUCERS AND THEIR ORIGIN IS RED MARROW.\nT CELLS DO NOT PRODUCE ANTIBODIES SOME ARE KILLERS,SOME ARE HELPERS, SOME UNDERGO PHAGOCYTOSIS ALL BECOME COMPOTENT IN LYMPHATIC TISSUE AND ESPECIALLY IN THE YOUNG THYMUS GALND AFTER A RED MARROW ORIGIN.
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The immune system is composed of many interdependent cell types that collectively protect the body from bacterial, parasitic, fungal, viral infections and from the growth of tumor cells. Many of these cell types have specialized functions. The cells of the immune system can engulf bacteria, kill parasites or tumor cells, or kill viral-infected cells. Often, these cells depend on the T helper subset for activation signals in the form of secretions formally known as cytokines, lymphokines, or more specifically interleukins. The purpose of this article is to review the organs, cell types and interactions between cells of the immune system as a commentary on their importance and interdependence on the T helper subset. Such an understanding may help comprehend the root of immune deficiencies, and perceive potential avenues that the immune system can be modulated in the case of specific diseases.
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check out http://www.immunesupport.com/library/showarticle.cfm/ID/3308  \n\nIt has 3 pages on what to take
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Antigens were originally defined as non-self molecules which bound specifically to antibodies. In practice, the term antigen is used to mean any molecule recognized by the immune system. \n\nAntigens which induce adaptive immunity are called immunogens. All immunogens are antigens, and are usually called antigens unless their ability to induce an immune response is being discussed. Some antigens, called haptens, are not immunogenic unless they are covalently linked to immunogenic carriers (usually proteins). Haptens can bind antibodies once the antibodies are produced, but haptens will not induce antibody synthesis on their own. Small non-protein organic molecules, for example the antibiotic penicillin, are haptens.\n\nImmunogenicity is influenced by \n\nthe chemical nature of the antigen. \nthe antigen's size. \nthe antigen's usual presence in the body. \nantigen dose and route and timing of administration. \nwhether the antigen is easily phagocytosed. \nwhether antigen is efficiently presented to T cells on MHC. \nthe maturity of the immune system and specific lymphocytes. \nNote that immunogenicity depends on the immune system as well as on the antigen. \n\nImmunogenicity is generally higher for proteins than for other organic molecules. Protein antigens, which are the predominant sort that activate helper T cells, consequently induce more B cell antibody production, synthesis of IgG or IgA, and generation of memory B and T cells. T-independent antigens, which activate only B cells, induce IgM synthesis but not other adaptive immune responses.\n\nImmunogenicity increases with molecular size and complexity. Haptens are generally non-proteins or they are too small to be immunogenic unless they are covalently attached to a carrier protein molecule. Some carbohydrate antigens can stimulate B cells to secrete IgM in the absence of T cell help but do not elicit IgG or memory cells. Human infants make poor responses to carbohydrate antigens, so early vaccinations with bacterial polysaccharide antigens employ protein carriers. Aggregated proteins are easily phagocytosed and more immunogenic than soluble proteins. Adjuvants, including bacterial products, alum, or oil emulsification of antigen, attract and activate antigen-presenting cells (dendritic cells and macrophages) and slow antigen release to prolong exposure and improve immunogenicity.\n\nEach part of the antigen bound by a unique antibody is called an epitope. Most proteins have several epitopes that are recognized by different B cells and induce a polyclonal antibody response. In a polyclonal response, several clones of B cells each make different antibodies, all able to bind to the same antigen but at different epitopes. Epitopes may be shared by closely related antigens (cross-reactivity), so that antibody made to tetanus toxoid binds tetanus toxin. A protein epitope may be a linear sequence of amino acids or it may be assembled by protein folding. Epitopes with definite three-dimensional shapes and charged amino acids are particularly well recognized by antibodies. External membrane and cell wall molecules, often present in many copies on the pathogen, are common B cell antigens. A small peptide of 4-6 amino acids could fit into an antibody binding site, but larger proteins have more extended epitopes across their surfaces.\n\nActive immunity is induced by exposure to antigen. Antigen dose and the route and timing of antigen contact, as well as immunogenicity, influence the magnitude and nature of the immune response. Very high or very low doses of antigen induce tolerance, the inability to respond to that antigen, while intermediate doses induce immunity. We are generally tolerant to cell-bound and soluble antigens present in our own bodies. Oral tolerance to foods is common, although some foods induce allergic reactions. \n\nAntigens encountered in body tissues through subcutaneous or intramuscular injection are carried by lymph and macrophages into the lymph
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Immune surveillance refers to the body's sensitivity to the presence of foreign organisms (bacteria, viruses, parasites), foreign tissue transplanted from a donor, or the body's own cells which will be recognized as "not-self" through malignant transformation (i.e. cancer cells) or in the development of autoimmune disease (e.g. rheumatoid arthritis).  In each of these instances the body's immune system is responding to the presence of surface markers called antigens, which are usually proteins.  All cells in the body produce surface antigens and display them on the cell membrane.  The precise structure of these antigens is genetically determined and differs between individuals (except for identical twins).  The components of the immune system recognize each individual's surface antigens as belonging to that person's "self" and does not react to them under ordinary circumstances.\n\nThe mechanisms of immune surveillance depend primarily on three cell types.  The first of these are the macrophages, large cells which engulf and devour foreign organisms such as bacteria.  The bacterial cells' surface antigens are processed by the macrophages, expressed on the surface of their cell membranes, and then "presented" to a second category of cells, the CR4+ T lymphocytes.  These white blood cells recognize the bacterial antigens as foreign and then cause the transformation of B lymphocytes into plasma cells, which will then produce antibodies specific for those antigens.  The antibodies can attach themselves to these surface antigens on the invading bacteria and facilitate their destruction by other T lymphocytes and the complement system.  Similar mechanisms are involved in the case of viral infections.  In both bacterial and viral infection immune surveillance during the first exposure often results in clinical illness, but results in immunization, the result of which is the production of T and B lymphocytes that "remember" the first exposure and trigger a faster, more effective response to subsequent exposures that prevents repeat occurrence of the same illness.  Note that this immunizing exposure can be either natural, in response to exposure to the "wild" organism, or artificial, in response to a modified form of the organism or its antigens (vaccination).\n\nStill other mechanisms, some involving antibody production and some involving only T lymphocyctes and natural killer cells, are involved in the detection and destruction of cancer cells, in the body's attack on its own tissues in autoimmune disease, and in the detection and rejection of foreign tissue from a transplant donor.  Research in transplant medicine has resulted in the successful development of drugs and other treatments that prevent rejection of transplanted organs.  Current research in clinical immunology is directed at identifying methods for enhancing immune surveillance and destruction of cancer cells, and also at identifying the causes and possible means of prevention of autoimmune disease.
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The body produces two types of antibodies. The first is designed to attack an antigen that has entered the body, to keep it from multiplying. This first type is stored in the lymph system throughout the body, and is assigned to attack antigens as they appear.\n\n The second type of antibody, the one you are concerned with, is formed to attack a specific microorganism. When a vaccine is administered into the body, it is a weakened or dead form of microorganism, which the body produces antibodies against. These antibodies remain in the body in great enough numbers to ward  off infection from that microorganism, in many cases, for the remainder of your life. The second type of antibody would only serve to protect the body from that microorganism for which it was originally formed ( the vaccination). Hope this helps some.
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T cells are one of the variety of white blood cells which are part of the immune system. The immune system as a whole learns very early to distinguish between 'self' and 'non-self' sorts of things. The test is largely like this: "is this thing I see something acceptable (ie, self)? If not, kill it." Although the question is posed and answered in a biochemical sort of way. Self is flagged, most fundamentally as near as we can tell, by the presence of Human Leucocyte Antigens (HLA) on the surface of cells. These are highly variable things, so variable that no other person anywhere is more than a tiny bit likely to have the same bunch of them on their cells. Except, of course, for identical twins. \n\nSo T-cells transplanted into you from someone else with fail the 'is this self?' test and will be attacked as 'foreign' by your immune system. They will not survive and will provide very little beneficial effect. It's called the transplant reaction and various aspects of it have earned several Nobel Prizes. \n\nMore speculatively, it may be that immune system tissues have learned to work together, and that, in each person, the exact details of just how to do so may vary. So how my T-cells work might be just enough different than yours that, even if they could survive inside you, they might not be able to interact with the rest of your immune system so as to help much. For instance, one of the things T-cells do is to talk to other immune system cells and direct their operations; if your immune system won't listen to my T-cells, much of what they'd be trying to do would be futile.  \n\nThere is quite a bit more to learn about the detailed workings of the immune system.\n\nBlood type differences (Types A, B, O are the major gropus, but there are many subgroups such as Rh (+/-), S, ...) are a simpler version of this self / non-self business, this time involving rather fewer genes and markers on blood cells. Nevertheless, there are some antibodies (yet another immune system mechanism) which use them to recognize self v non-self, and a transfusion of the wrong blood type will cause a very severe reaction, so severe as to be life-threatening.
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Cell-Mediated Immunity\nIndex to this page \nDelayed-Type Hypersensitivity (DTH) \nContact Sensitivity \nKilling intracellular parasites \nAnti-Viral Immunity \nGraft Rejection \nGraft-versus-host disease \n \nThe human body can respond to antigen in many different ways. These fall into two major categories: \nantibody-mediated immunity. Antibodies, dissolved in blood, lymph, and other body fluids bind the antigen and trigger a response to it. (This form of immunity is also called humoral immunity.) Discussion of antibodies \n\ncell-mediated immunity (CMI). T cells (lymphocytes) bind to the surface of other cells that display the antigen and trigger a response. The response may involve\nother lymphocytes and \nany of the other white blood cells (leukocytes)
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Antantibodies against antigen are produced by subpopulation of B - cells (B-lymphocytes) activated by antigen against which antibodies are produced.\n\nAntibodies are produced mainly against proteins which contains highly antigenic epitopes. Some polysaccharides may be highly antigenic. (but not starch ...)
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When an unknown virus, microbe, protein, etc (foreign stuff) called in general antigen, enters the organism, the organism responses to it, in a specific way and tries to fight it. Immunology studies the agents in the organism that respond to the antigen (called antibodies) and the mechanisms by which they fight it.