Applications of Immunology.ppt

1、1,Applications of Immunology,Talaro Chapter 16,2,Acquired Immunity,Natural Immunity Acquired as part of normal life experiences Artificial Immunity Acquired through vaccination Active Immunity Results when a person is challenged with Ag that stimulates production of Ab Memory Passive Immunity Prefor

2、med Ab are donated to an individual Acts immediately but is short term No memory Breast feeding Gamma globulin Monoclonal antibodies,3,4,Vaccines,Provide an antigenic stimulus that does not cause disease Attenuated strain Tissue culture or unnatural / unusual host Hypovirulent Dead whole cells or in

3、activated viruses Heat, formalin, UV irradiation Purified antigen subunits from cells or viruses Surface antigens produce via rDNA technology DNA vaccines Produces long lasting protective immunity Edward Jenner (page 476) www.sc.edu/library/spcoll/nathist/jenner2.html Cowpox Smallpox Variola Control

4、led experiments Vaccinia virus Cultured cow pox virus for many years Small pox eradicated in 1973,Why did the vaccinia virus work?,Immunization using a closely related, less pathogenic organism to give protection against a more pathogenic one.,5,Cowpox on human forearm www.cdc.gov,Smallpox www.cdc.g

5、ov,6,7,Vaccination Success,Small pox 2 million people a year died from small pox until 1967 The World Health Organization initiated an immunizationcampaign that eradicated small pox in 12 years Poliomyelitis (polio) This virus attacks the motor neurons of the brain and spinal cordCauses paralysis an

6、d deathImmunization campaigns since the 1950s have virtually eradicated polio in developed countries,www.who.int/immunization_safety/en/ www.cdc.gov,news.bbc.co.uk,8,Polio Eradication,9,Haemophilus influenzae type b Mistakenly believed to have caused influenza Type b strains accounted for majority o

7、f bacterial meningitis Meningitis, pneumonia, and epiglottitis Was the leading cause of bacterial meningitis of children 5 years or younger 1/200 children contracted Hib Incidence has decreased 99% since the vaccine was introduced,www.cdc.gov,20,000 cases per year in the early 1980s1,247 in 2000,10,

8、Vaccines cause disease Disease is no longer a threat in my country Cost of vaccination Difficulty reaching vaccination center Not recommended by my physician Safety concernsSide effectsSIDSAutismDepress the immune systemMercury Poisoning Religious beliefs,www.who.int/immunization_safety/aefi/immuniz

9、ation_misconceptions/en/index.html,Herd Immunity Protection from a disease among unvaccinated individuals occurs when 90% of a population is immunized.% depends on the disease & vaccine,Content and Design Attributes of Antivaccination Web Sites Robert M. Wolfe, MD; Lisa K. Sharp, PhD; Martin S. Lips

10、ky, MD JAMA 2002 287:3245-3248.,11,Polio Outbreak Occurs Among Amish Families In Minnesota by David Brown Washington Post Staff Writer October 14, 2005 The first outbreak of polio in the United States in 26 years occurred earlier this fall in an Amish community in central Minnesota, state and federa

11、l health officials reported yesterday. Four children have been infected with the virus, although none has become paralyzed. The Amish typically decline to vaccinate their children. The last large outbreak of polio occurred in numerous Amish communities in several states in 1979.,Fears Rising Over Me

12、asles Outbreaks by ROBERT A. HAMILTON STATE health officials are preparing for what they fear could be a major outbreak of measles when students who attend Boston University return home next week for spring break. Last week, a measles case was reported in Fairfield, an 18-year-old Boston University

13、freshman who returned home eight days ago with cold symptoms and by Tuesday was in the hospital. We expect a lot more students will be returning to Connecticut next week, for the spring break, the program director of the state immunization program, Dr. Charles H. Alexander, . March 3, 1985 The New Y

14、ork Times,12,irradiation,hypovirulent,13,14,15,Serology,A part of immunology that attempts to detect signs of infection in a patients serum Use Abs that specifically bind to Ag Ag-Ab reactions are visible by Clumps Precipitates Color changes Release of radioactivity The most effective tests have hig

15、h specificity and sensitivity.,leukocytes,Abs Proteins Clotting factors Hormones Nutrients Ions,Clear fluid from clotted blood,Isolate Ab from serum,16,Agglutination Test,Ab and Ag from a whole cell crosslink Forming complexes that settle out and from visible clumps in the test chamber,Isolate Abs f

16、rom patient,17,Agglutination,Contains patientAbs,18,Agglutination,Contains Abs for the specific pathogen,19,Precipitation Tests,Soluble Ag is precipitated Cloudy or opaque zone Many variations are used to maximize this technique Measure optical density,20,Calculate titer The highest dilution of seru

17、m that shows a positive result,21,Enzyme-linked immunosorbent assay (ELISA),Detect unknown Ag or Ab A positive result is visualized when a colored product is released by an enzyme-substrate reaction,Anti-immunoglobulin Ab complexed to an enzyme,conjugate,22,Perform a virtual ELISA courtesy of the Ho

18、ward Hughes Medical Institute www.hhmi.org/biointeractive/vlabs/,23,Radioimmunoassay Ag or Abs are labeled with radioactive isotopes and traced,24,ELISA www.biology.arizona.edu,Positive Rxn,Negative Rxn,+ is 0.5 or greater,Indeterminate 0.300 0.495,- is 0.300 or less,25,More sensitive than ELSIA Les

19、s chance of a false + Detects specific Ag or Ab proteins in serum Separates proteins into bands via gel electrophoresis Protein bands are transferred to a membrane Specific Abs are used to “probe” the membrane Primary Ab are from patient Secondary Ab Anti-immunoglobulin Ab complex to an enzyme Color

20、less substrate Colormetric,Western Blot,Western Blot for a HIV on page 487,26,Western Blot for HIV www.biology.arizona.edu,Serum proteins (virus) separated via electrophoresis. Transferred to a membrane.The primary Abs from the serum of a patient is added and will react to the HIV proteins (above).T

21、he secondary Ab is an anti-immunoglobulin conjugated to an enzyme. This Ab is specific for the primary Abs. A colorless substrate is cleaved if the anti-immunoglobulin conjugated to the primary Ab.,27,Band Pattern Interpretation Lane 1, HIV+ serum (positive control) Lane 2, HIV- serum (negative cont

22、rol) Lane A, Patient A Lane B, Patient B Lane C, Patient C,Patient A is Patient B is Patient C is +,28,29,Fluorescent Ab (FAbs) either directly or indirectly to visualize cells or cell aggregates,Immunofluorescence,30,Monoclonal Antibodies (Mab),Single specificity antibodies formed by fusing a mouse

23、 B cell with a myeloma cell A malignant tumor formed by the cells of the bone marrow Used in diagnosis of disease, identification of microbes and therapy,31,Immunize animalHarvest spleenFuse B & myeloma HybridomaImmortalScreen hybridomas for Absdirected against antigen of interest,Hybridomas produce

24、 antibody thatrecognize single epitopeProduce uniform, highly specific Ab in large supplyMultiple practical applications Diagnostic tests ELISA & Western BlotsImmunosuppressive therapy for transplants Prevent action of TCAnticancer drugsAntitoxinsIdentify a pathogenPurification of an important prote

25、inPrecipitate,32,Zenapax Prevent rejection in organ transplantation, especially in kidney transplants.,Mylotarg Acute myeloid leukemia (AML),Remicade Auto-immune disorders like Crohns disease and rheumatoid arthritis Target is tumor necrosis factor,Rituxan Treat a variety of non-Hodgkins lymphomas. Target and destroy non-Hodgkins lymphoma cells.,Monoclonals on the Market,Herceptin Blocks the effects of the growth factor protein HER2, which transmits growth signals to breast cancer cells. Causes tumor shrinkage.,Additional information at www.fda.gov,