Bioscience 2 - Adaptive/Specific Immunity Student Guide PDF

Tutorial Module 6 **Student Guide** **Bioscience 2** **Adaptive/specific immunity** Resource: [Chapter 21](https://ebookcentral.proquest.com/lib/uwsau/reader.action?docID=5573766&ppg=814), Marieb, E. N. & Hoehn, K. (2019). *Human anatomy & physiology* (11^th^ Global ed). Harlow, UK: Pearson Educ...

Tutorial Module 6 **Student Guide** **Bioscience 2** **Adaptive/specific immunity** Resource: [Chapter 21](https://ebookcentral.proquest.com/lib/uwsau/reader.action?docID=5573766&ppg=814), Marieb, E. N. & Hoehn, K. (2019). *Human anatomy & physiology* (11^th^ Global ed). Harlow, UK: Pearson Education **[Video on *The Immune Response*:]** Please watch this video in your vUWS site. **Pre tutorial revision** Connect each defence term in the first column with a corresponding term in the second column with a line. ***[Defence terms]*** ***[Corresponding term]*** ----------------------------------- -- ----------------------------------------------------------- First line of defence B\) AIR, fever, interferons Second line of defence C\) Inflammatory response *and* skin and mucous membranes Third line of defence A\) Intact skin and mucous membranes Innate defence system D\) Immune response Adaptive defence system D\) Immune response The *adaptive defence system*, also known as *specific immunity*, involves the activation of specific lymphocytes to protect the body against disease. The adaptive defence system is different to the innate defence system as it: - is a tailored response to a specific foreign substance - is distributed throughout the body - generates a memory of the encounter The two main lymphocytes involved in specific immunity are the B and T lymphocytes. **Q1.** Circle the correct word in the following sentences: **B lymphocytes** are involved in the humoral/cellular or antibody-mediated immunity. **T lymphocytes** are involved in the humoral/cellular or cell-mediated immunity. The following figure illustrates the formation, maturation, and activation of the B and T lymphocytes. [See fig 21.8 on page 825](https://ebookcentral.proquest.com/lib/uwsau/reader.action?docID=5573766&ppg=826) (Marieb & Hoehn, 2019). **Q2.** Complete the following sentences using the words provided below. You can use the words and letters more than once. *bone marrow, lymph nodes, primary, secondary, blood, antigen challenge, thymus gland* Both T and B lymphocyte precursors originate in the \_\_\_\_\_\_\_\_\_. The immature T lymphocytes then mature and develop immunocompetency in the \_\_\_\_\_\_\_\_\_\_\_\_\_ whereas the immature B lymphocytes mature and develop immunocompetency in the \_\_\_\_. The immunocompetent B and T lymphocytes then seed the \_\_\_\_\_\_\_\_\_\_\_ where \_\_\_\_\_\_ and clonal selection are most likely to occur. Activated immunocompetent B and T cells recirculate in the \_\_\_\_\_\_\_\_\_\_\_. The thymus and red bone marrow represent \_\_\_\_ lymphoid organs (location where lymphocytes mature) while the lymph nodes are \_\_\_\_ lymphoid organs (location where lymphocytes encounter antigens). **Q3.** As preparation for the Q4, connect the term with the appropriate definition/role. **Term** **Definition/role** ------------------------ -- ----------------------------------------------------------------------------------------------------------------------------- Antigen Chemical messengers that activate various cells of the specific & non-specific immune system Helper T cell (CD4) Proteins that attach to antigens and contribute to destruction of foreign cells Cytokines Specialised cells capable of recalling an encounter with an infection/antigen Cytotoxic T cell (CD8) Destroy cancer and infected cells as part of the cell mediated response B cells Foreign substance capable of activating the immune system. Present on surface of microorganisms Antibodies Central role in both humoral & cellular immunity. Releases cytokines to activate CD8, B cells and non-specific killer cells Memory cells Cells of the humoral immune system; turn into plasma cells to secrete antibodies Further explanation of the above terms will take place in Q4 **Q4.** a. Examine figure below which is from the older edition of Marieb & Hoehn (or [see page 840-841](https://ebookcentral.proquest.com/lib/uwsau/reader.action?docID=5573766&ppg=841) of Marieb & Hoehn, 2019) and use it to explain how the primary immune response works and the roles B and T lymphocytes (humoral and cell mediated divisions) play in the immune system. b. Can you give three reasons why Helper T cells are crucial to our immunity? c. What would happen if Helper T cells count were to drop dramatically due to viral infection? Is there a viral infection capable of doing this? **Q5. Primary & Secondary immune responses** You are on placement, and you sustain a needlestick injury which introduces the Hepatitis B virus into your body. Draw a diagram to illustrate your immune response given that you had the complete immunisation course for HBV last year. **Q6. Antibodies** Antibodies, also called immunoglobulin (Ig), are proteins found in body fluids that are produced by mature B cells (plasma cells) in response to a challenge by an antigen. There are five classes of immunoglobulins (IgG, IgA, IgM, IgD and IgE), which are characterised by antigenic, structural and functional differences (see below, [Fig. 12.9](https://www-clinicalkey-com-au.ezproxy.uws.edu.au/nursing/#!/content/book/3-s2.0-B9780729543910000211) in Craft & Gordon). Please review the [Chapter 12](https://www-clinicalkey-com-au.ezproxy.uws.edu.au/nursing/#!/content/book/3-s2.0-B9780729543910000211) (The structure and function of the immune system) in Understanding pathophysiology (2023), by Craft & Gordon, and match each immunoglobulin (Ig) to its specific characteristic in the table below.  **Immunoglobulin** **Characteristics** -------------------- -- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- IgA Is the most abundant class, constituting up to 80% of the immunoglobulin in the blood and accounting for most of the protective activity against infections. IgD Is found in the blood and body fluids such as tears, saliva and digestive fluids and therefore is important in preventing infectious microorganisms from attaching to epithelial barriers. IgE Is the largest of the immunoglobulins and is the first antibody produced during the initial, or primary, response to antigen. IgG Its primary function is as an antigen receptor on the surface of early B cells and for the maturation of B cells. IgM It has very a specialised function as a mediator of many common allergic responses with high levels in the blood in individuals with allergies. **Q7. Allergic reaction** Carla who has allergic rhinitis (commonly called hay fever) suffers, particularly in Spring, from an itching and congested nose, profuse watery drainage, sneezing and eye irritation, with redness of the conjunctiva. She takes an antihistamine to prevent the symptoms. Allergic reactions involve a two-stage process of: 1. Initial contact with the allergen, where mast cells and basophils become sensitised/primed to the allergen 2. Subsequent contact with the allergen, where the allergic reaction takes place Use the image below (Fig. 15.1 from [Chapter 15](https://www-clinicalkey-com-au.ezproxy.uws.edu.au/nursing/#!/content/3-s2.0-B9780729543910000247) of Craft & Gordon) and textbooks, to answer the following questions. Full size image for \'Alterations of immune function across the life span\' 1. Initial contact with allergen a. What is the allergen that Carla is allergic to? Can you name other common allergens? b. What specific lymphocyte is involved in the production of the antibodies during the initial allergic process? c. What substance do these cells secrete? d. What do these secreted substances attach to? e. Briefly outline the steps involved in the initial contact of the allergen to prime the mast cells and basophils. 2. Subsequent exposure to the allergen f. Outline the allergic reaction that will take place in the body every time Carla comes in contact with the allergen. g. How does antihistamine medication work? **Q8.** Examine the National Immunisation Program schedule. And Occupational assessment, screening etc policy: a. ***What are the benefits of vaccinating individuals?*** b. Why do some vaccines require repeated doses of the same vaccine as part of the schedule (such as Infanrix^®^ hexa at 2, 4 & 6 months)? c. Influenza is a serious disease responsible for the hospitalisation and death of thousands each year. The flu vaccine was introduced to reduce the risk of developing influenza and provides protection for those most at risk such as infants, children, elderly & those with a weak immune system. Why is it necessary to administer the flu vaccine annually?