Immunology lecture 1.ppt
- 1. Essentials of Immunology Dr. Farheen Bhatti PhD (Biotechnology) Lecture-1
- 2. What is Immunology? Immunology is a branch of biology that covers the study of immune systems in all organisms. or The study of the body's defenses is called immunology. or A science that deals with the immune system and the cell-mediated and humoral aspects of immunity and immune responses.
- 3. When an Immune System Triggers? The immune system is typically associated with defending against foreign intruders (unwanted attack), called pathogens, but it can fight against various disorders including metabolic, cardiovascular, and neurodegenerative conditions such as Alzheimer’s. The immune system protects us from infection through various lines of defence. If the immune system is not functioning as it should, it can result in various diseases, such as autoimmunity, allergy and cancer etc.
- 5. Categories of Immune System The immune system has been divided into I. Innate immune system II. An acquired or adaptive immune system This is further divided into humoral (or antibody) cell-mediated immunity
- 6. Innate immunity is the first and second lines of defence and is non-specific. That is, the responses are the same for all potential pathogens, no matter how different they may be. Innate immunity (first-line of defense) includes physical barriers (e.g. skin, saliva etc.) and cells (e.g. macrophages, neutrophils, basophils, mast cells etc.) include second line of defense. These components ‘are ready to go’ and protect an organism for the first few days of infection. In some cases, this is enough to clear the pathogen, but in other instances the first defence becomes overwhelmed and a second line of defence kicks in. Innate Immunity
- 7. Adaptive immunity is the third line of defence which involves building up memory of encountered infections so can mount an enhanced response specific to the pathogen or foreign substance. Adaptive immunity involves antibodies, which generally target foreign pathogens roaming free in the bloodstream. It is based on B-cells and T-cells, which are directed especially towards pathogens that have colonised cells and can directly kill infected cells or help to control the antibody response. Adaptive Immunity
- 8. Antigen: An antigen is a substance that ignites the immune response. The cells involved in recognizing the antigen are Lymphocytes. Once they recognize, they secrete antibodies. Antibody: Antibody is a proteins that neutralize the disease-causing microorganisms. Antibodies don’t directly kill pathogens. The humoral (antibody) response is defined as the interaction between antibodies and antigens. Allergenicity: Allergenicity or allergenic potential: the potential of a material to cause sensitisation and allergic reactions, frequently associated with IgE antibody. The humoral (or antibody)
- 9. Cell-mediated immunity is an immune response that does not involve antibodies. Rather, cell mediated immunity is the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to antigen. Autoimmunity Autoimmunity is the system of immune responses of an organism against its own healthy cells and tissues. Any disease that results from such an aberrant immune response is termed an "autoimmune disease". Cell Mediated Immunity
- 10. The cells of the immune system can be categorized as: lymphocytes (T-cells, B-cells, Mast cells and NK cells) neutrophils, and monocytes/macrophages These are all types of white blood cells. The major proteins of the immune system are predominantly signaling proteins (often called cytokines), antibodies, and complement proteins. The Cells of Immune System
- 11. Innate Immunity vs Adaptive Immunity
- 12. Types of Adaptive Immunity