PPT-Antigens and the Immune Response

Assist Professor Dr Sinan Bahjat MBChB MSc FIBMS Antigens are molecules that react with antibodies whereas immunogens are molecules that induce an immune response. Defense from injury & illness. BIOL.10A . Describe the interactions that occur among systems that perform the . functions of . regulation, nutrient absorption, reproduction, and . defense from injury or illness . Types of Antigen. Complete Antigen: Substances which can induce antibody formation by themselves. . Haptens: substances which are unable to induce antibody formation on its own but can become immunogenic, i.e., capable of inducing antibodies, when covalently linked to proteins known as carrier proteins.. 1. Immunity: Two Intrinsic Defense Systems. Innate. (nonspecific) system responds quickly and consists of:. First line of defense. – skin and mucosa prevent entry of microorganisms. Second line of defense. LYMPHOCYTES. Are the key cells of the immune system. Two types: B and T. Both produced in the bone marrow. B matures in the bone marrow. T matures in the thymus. Immunocompetency. B and T lymphocytes must recognize “self.”. By. . Someshwar.K. M.PHARM. II - SEMESTER . . . Department of Pharmaceutics. University College of Pharmaceutical Sciences,. KAKATIYA UNIVERSITY. Chapter 4. Introduction. Molecules recognized as “non-self” are antigens. Several mechanisms to protect itself . First level of protection include physical and biochemical-skin, acid in stomach. Second level of protection phagocytic cells, enzymes, and proteins. Dr. Suzan Y.. Antigen. :. It s a substance that may be specifically bound by an antibody (. Ab. ) molecule or T cell receptors (TCR). When this binding lead to the activation of B cells or T cells ,this substance is known as . 1. st. Lecture. Definitions. Immunity. . (. Latin . “. immunitas. ”) is a universal biological phenomenon that develops many programs based on the unique genotype of the body (“self”) in foreign surroundings, from the birth of the body to its death. There are two major types of immunity, . Immune Response. Adaptive Immune. 2. Adaptive or Acquired Immune Response. Protects against infectious agents and abnormal body cells . Amplifies the inflammatory . response. Activates complement. 3. By: Dr. Suzan Y.. SPECIFIC COMPONENTS OF IMMUNE SYSTEM: LYMPHOCYTES. B-Lymphocytes (“B cells”). T- Lymphocytes (“T cells”). Natural Killer Cells (NK cells). Memory Cells. Suppressor Cells. They have different functions in specific immunity. Transgenic mice from teratocarcinoma cells. https://. www.nobelprize.org. /prizes/medicine/2007/advanced-information/. genome. the mouse. to manipulate. using E.C. cells. Next:. What are some of the molecules recognized by this immune system?. Immunological unresponsiveness to self is referred to as . tolerance. or . self-tolerance. Very important to human health. How is this achieved?. -cells with receptors for self-antigens are destroyed in the thymus or bone marrow (central tolerance). An . antigen. is anything that elicits an adaptive immune response. These are molecules that trigger a specific immune response, eg., components of bacterial cell wall, capsule, pili, flagella, external and internal proteins of viruses, fungi and protozoa, toxins, nonself foreign substances like proteins, nucleoproteins, polysaccharides, some glycoproteins. B. Antigen (Ag). A substance that reacts with the products of a specific immune response.. C. Hapten. A substance that is non-immunogenic but which can react with the products of a specific immune response..