Lesson 3: Immunology and Enzymology

• Organs for Immunology

  A) Mucous Membrane

  B) Lymphatic Vessels

  C) Tonsils

  D) Thymus

  E) Skin

  F) Bone Marrow

  G) Lymph Nodes

  H) Spleen

  I) Lymphatic Vessels

  
• Immunology - the branch of biomedical science that deals with the response of an organism to antigenic challenges and its recognition of what is self and what is not
• Immunology - is a broad branch of biomedical science that covers the study of all aspects of the immune system in all organisms
• Malfunctions of the Immune System:

  • Autoimmune Diseases
  • Hypersensitivities
  • Immune Deficiency
  • Transplant rejection
• Immunity - state of protection from infectious diseases
• Immune System - remarkably versatile defense system that has evolved to protect animals from invading pathogenic microorganisms and cancer
• Cells related to Immunity

  A) Multipotential Hematopoietic Stem Cell

  B) Common Myeloid Progenitor

  C) Common Myeloid Progenitor

  D) Megakaryocyte

  E) Thrombocytes

  F) Erythrocytes

  G) Mast Cell

  H) Myeloblast

  I) Basophil

  J) Neutrophil

  K) Eosinophil

  L) Monocyte

  M) Macrophages

  N) Natural Killer Cells

  O) Small Lymphocyte

  P) T-Lymphocyte

  Q) B-Lymphocytes

  R) Plasma Cells

  
• Stem Cell - "master cell"; potential to restore, repair, replace, and regenerate cells
• Basophils (blood) & Mast Cells (tissue) - both create an environment that is conductive to defense by releasing chemicals; do not attack other cells
• Histamine - promotes vasodilation and increased vascular permeability
• Heparin - is an anti-coagulant
• Prostaglandins - hormones that regulate inflammation and pain, which includes vasodilation, pain, and fever
• Pyrogen - any substance that elicits fever
• Chemotactic Factors - chemicals that attract other immune cells
• Eosinophils - combat parasites by releasing cytotoxic chemicals
• Macrophages - derived from monocytes; defend body through phagocytosis
• Dendritic Cells - antigen-presenting cell
• Antigen Presentation - present a microbe fragment on its surface; this will communicate with and stimulate T-cells in adaptive immunity
• Chinese (1500 A.D) custom of inhaling crusts from smallpox lesions to prevent the development of smallpox in later life.
• In 1796 an English surgeon, Edward Jenner, developed the concept of vaccination by immunizing an 8 year-old boy against smallpox using cowpox fluid.
• Louis Pasteur- demonstrated that it was possible to attenuate, or weaken, a pathogen and administer the attenuated strain as a vaccine.
• In 1885, Pasteur administered his first vaccine to a human, a young boy who had been bitten repeatedly by a rabid dog.
• Innate Immunity - a type of general protection; everyone is born with it
• First Line of Defense - a surface protection composed of anatomical and physiological barriers
• First Line of Defense:

  • Physical Barriers
  • Chemical Barriers
  • Genetic Barriers
• Second Line of Defense - a cellular and chemical system that comes into play if pathogens make it past the surface defenses
• Second Line of Defense:

  • Inflammatory Response
  • Interferons
  • Phagocytosis
  • Complement
• Third Line of Defense - includes specific host defenses that must be developed uniquely for each microbe
• Acquired Immunity - immunity that develops during life
• Adaptive immunity - develops throughout our lives; developed when exposed to diseases or when immunized against them with vaccines.
• Passive immunity - "borrowed" from another source and it lasts for a short time
• Enzymology - a field of study that deals with a specific group of proteins called enzymes
• Enzymes - accelerate specific chemical reactions in a biological system, and these reactions are essential to the growth, development, adaptation, and survival of the organism
• Enzyme - acts as a biological catalyst \
• Coenzyme - small nonprotein molecules that are associated with some enzymes; undergo changes to compensate for the transformations occurring in the substrate.
• Apoenzyme - becomes active by binding with coenzyme or cofactor
• Holoenzyme - formed when associated coenzyme or cofactor binds to the enzyme active site
• Emil Fischer in 1894 - suggested that enzyme are very specific; states that molecules bind to fit exactly with another
• Lock-and-Key Theory - proposed by Emil Fischer in 1894
• Induce Fit Model - enzyme and the substrate undergo structural changes to attain an optimal fit