» Cancer Lecture
Episode 24: Doctor Dan gives part 2 of his Cancer lecture series available in full at www.Medical-Mastermind-Community.com.
» Transplantation Immunology
Told to know these for “passage of the exam” Autograph- skin transplant; no immunosuppression Syngenic or Isograft- identical twins Allograft/Homograft- genetically different of same species; need immunosuppression Xenograft/Heterograft- 2 different species Primary and Secondary Allograft rejection T cell mediated – memory and specificity First set rejection- (7-30 days)- organ and tissue allografts are rejected by [...]
» Major Histocompatability Complex
Introduction HLA= Human Leukocyte Antigen Located on Chromosome 6 3 groups of proteins (I,II,III) Class I A,B,or C Class II DP,DQ,DR Class III complement components (C4, B1, C2) MHC Class I Molecules Location- A,B,C associated w/ b2-microglobulin on cell surface co-dominant (half from mommy and ½ from daddy) with b2-microglobulin forms 4 domains binds oligopeptides [...]
» Introduction to Immunology
Immunity- “to protect” Purpose- to distinguish between self and non-self; destroy non-self Acquired Immunity- response of lymphocytes to an antigen. The emphasis in medical school is on acquired immunity. History Cowpox- Jenner- 1798 Attenuated Vaccines- Pasteur- 1880 Blood Groups- Landsteiner- 1900 Innate Immunity all multicellular animals NON-SPECIFIC!!!!! Present at birth Initial Barrier Mediated by Physical [...]
» Elements of Innate and Acquired Immunity
Innate or Natural Immunity 1. Physiological barriers Skin Epidermis, Acid pH of sweat, lysozyme Mucous membranes Mucus, hydrolytic and proteolytic enzymes, Low pH in vagina and Stomach 2. Phagocytosis General Properties a. Stages 1. ingestion 2. formation of phagocytic vacuole (phagosome) 3. fusion of phagosome with lysosome 4. destruction of bacterium of virus b. Opsonization- [...]
» Infection and Immunity
Bacterial Ab (Immune complexes and Cytotoxicity) Mycobacterial DTH and granulomatous reactions Viral Ab (Neutralization), TCTL and DTH Protozoal DTH and Ab Worms Ab (Atopis, ADCC) and granulomatous rxns Fungal DTH and granulomatous rxns 3 phases of response to initial infection: 1. Early, innate and non-specific response (0-4 hrs) preformed effector cells and molecules 2. 4 [...]
» Control Mechanisms in the Immune Response
Goal: To recognize but not respond to self; to recognize and respond to non-self for a long enough period with enough intensity to result in immunomodulation Development of B and T Cell Repertoire (How do we get the ammo?) both B and T cells’ specificities are conferred via RANDOM gene rearrangement We have a ton [...]
» Immunology of AIDS
HIV Hiv-1- most common in U.S. and Europe HIV-2- prevalent in Africa (50% homology w/ HIV-1) Retroviruses- from DNA from RNA genome There are oncogenic (HTLV) and cytolytic (HIV) Lentiviruses- slow acting cytolytic retroviruses (HIV) HIV Genome and Structure 9000 bp segment of s.s. RNA gene products are cleaved by HIV protease Important proteins gp120 [...]
» Immunogenicity
Antigens (Ag)- substances able to induce a specific active immune response Immunogens- are agents that are capable of inducing an immune response Antigens- agents capable of binding specifically to components of the immune system such as lymphocytes or antibodies. All immunogens are antigens, but not all antigens are immunogens Some substances require another substance to [...]
» Immunodeficiencies
Definitions 1. immunodeficiency disorders- diverse group of illnesses which, as a result of one or more abnormalities of the immune system, predispose an individual to infection. can involve malfunction of blood cells (lymphs, granulo., monos) soluble molecules- (Ab, complement) CAUSES inherited genetic trait (PRIMARY) unrelated illness or agent (SECONDARY) Incidence 1: 10,000, except for certain [...]
» Immunoglobulin and T Cell Receptor Structure
Immunoglobulins are found in large quantities in blood serum The gamma region contains most of the Ab in an immunized individual Heterogeneous Structure of Light and Heavy Chains 4-chain structure 2 identical heavies and 2 identical lights Light Chains Two types of light chains, k and l. the difference is in the amino acid sequence [...]
» The Genetic Basis of Antibody Structure
Variable region genes are encoded by multiple exons on the same chromosome Light chain variable region genes are produced by DNA rearrangements that join a VL and a JL gene from a pool of many such genes that are variable in sequence Heavy chain variable regions are similarly produced but use a different set of [...]
» Fever and Alterations in Body Temperature
I. Historical Aspects- A. Fever was first recorded in ancient hieroglyphics several thousand years BC. B. Hippocrates had a humoral theory about fever being a sign of ill health. C. In 1868 Mr. Wunderlich developed the thermometer and established fever as one of the 4 vital signs. D. Around 1900, Sir Wm. Osler described the [...]
» Complement
A system of more than 30 serum and cell surface proteins that is involved in numerous function in inflammation and immunity Primary humoral defense system against bacterial and viral infections heat labile (can be destroyed by heating serum) most of the complement proteins are produced by the liver hepatocytes C3 is the most abundant serum [...]
» Properties of Cells involved in the Immune Response
Intro all blood cells and Lymphocytes come from pluripotent stem cells in the bone marrow We can distinguish stem cells from other bone marrow components Developmental Pathway Platelets, Erythrocytes, Eosinophils, Neutrophils, Basophils, Monocytes, Macrophages Myeloid Stem Cell Bone Marrow Pluripotential Stem Cell Lymphoid Stem Cell ¯ T Cell Precursor B Cell Precursor ¯ [...]
» Cell-Mediated Immunological Reactions
Ø CMI- immune reactions in which T cells play a central role as effector cells instead of regulatory cells includes T-cell cytotoxicity and Delayed type Hypersensitivity Granulomatous responses usually result from DTH reactions to poorly degradable antigens, although Ab responses can also be involved. T Cell Cytotoxicity T mediated cellular cytotoxicity involving direct contact between [...]
» Autoimmunity
Definition: An endogenous immune response (autoantibody and/or autoreactive T cell) to an endogenous antigen Normal Occurences Probably occur all of the time to help clear defective or denatured molecules These are rapidly cleared by the RE system Abnormal Occurences when large amounts or autoantibodies or autoreactive T cells are produced which damage host tissue, an [...]
» Antigen-Antibody Interactions
once Ab have been made they can be used for a variety of diagnostic assays in the lab to detect the presence or absence of a particular antigen or bacterium or virus in a sample For example, the use of Ab specific for the myriad of RBC antigens has made routine transfusion possible as well [...]
» Antibody-Mediated Immunologic Reactions
Ø Antibody (Humoral) mediated immunity- extracellular bacteria or bacterial products Ø Cell Mediated Immunity (CMI)- primarily operates against intracellular viral, bacterial, as well as fungal antigens Ø “DOUBLE-EDGE SWORD”- in most cases your immune system is protective, but it can also be destructive. Ø Immunopathology- tissue damage resulting from the immune response allergies, hypersensitive reactions, [...]
» Activitation of B and T Cells by Antigen
Remember innate vs. adaptive Remember anitgens have certain properties that allow them to be immunogenic. Such as: size, foreigness, polysaccharides Cytokines Properties MODULATE IMMUNE/ INFLAMMATORY RESPONSES (allow for balance) inc. small peptides and glycoproteins Made by variety of cell types including accessory cells leukocytes somatic cells short ½ life; one cell can make many different [...]
» Antibody Structure and Function
Structural Features of IgG 2 L-chain domains; 4 H-chain domains Inter and intrachain disulfide bonds hold IgG together Single carbohydrate moiety in CH2 domain (plays role in transport/secretion) Biologic Properties of IgG (8) 1. Agglutination & Precipitate Formation 2. Placental Passage: selectively passed through placenta (except IgG2) to provide passive immunity to fetus; transfer mediate [...]
