1.医学分子生物学 introduction

医学免疫学Introduction toImmunologyThe real world: dancing with microorganismsfungi virus bacteriaparasite •We live surrounded by microorganisms, many of which cause disease.The bacteria on a needle pointThe picture about black death（plague）6th century AD（520～565）、14th century AD（1346～1665）、19th century （1894～1920）: 3 times pandemic, death population: 25M～100MPulmonary tuberculosis patientFungi infection in the skinRoundworm infectionA victim of smallpoxAcquired immunodeficiency syndrome, AIDSHuman immunodeficiencyvirus, HIVPneumocystis carinii CMV infection Kaposi’s tumorSARS: severe acute respiratory syndromeH7N9Bird flu and MERS MERS: middle east respiratory syndromeZika virus infection has rapidly emerged as a global threatMicrocephaly cases•Despite this continual exposure to microorganisms we become ill only rarely.•How does the body defend itself?•When infection does occur, how does the body eliminate the invader and cure itself?•And why do we develop long-lasting immunity to many infectious diseases encountered once and overcome?•…………•These are the questions addressed by immunology.Immunology•The study of the way in which the body defends itself against invading organisms or internal invaders (tumors).•The study of the body’s defense against disease, especially infectious disease.•Contributing critical tools for research, diagnosis, prevention and treatment of a wide range of human diseases.•An integral part of medical study.• A relatively new scienceHistory of Immunology •Experience immunology phase（17-19century）•Classical immunology phase（19-20century）•Modern immunolgy phase（20century to now）Edward Jenner and smallpoxvaccinationThe origin of Immunology is usually attributed to Edward Jenner, who demonstrated in the late 18th century that inoculation with the relatively mild cowpox, or vaccinia, could protect against smallpox. He called the procedure vaccination, and this term is still used to describe the inoculation of healthy individuals with weakened or attenuated strains of disease-causing agents to provide protection from disease.Robert Koch and some importantpathogensAnthrax bacteriaTubercle bacillusComma bacillus Robert Koch proved in the19th century that theinfectious disease are causedby microorganisms, eachone responsible for aparticular disease.Microbiologist: Louis PasteurDemonstrated thatmicroorganisms growthcontributes to infectiousdiseases;Invented rabies vaccineand cholera vaccine;Created pasteurization.Emil von Behring and Shibasaburo KitasatoThey found antiserum againstdiphtheria toxin andtetanus toxin，aswell as createdserotherapy.Phagocyte and Elie MetchnikoffElie discovered that many microorganisma could be engulfed and digested by phagocytic cells, which he called macrophages.Lymphocytes were foundLymphocytes are mostly small and inactive cells, and include B lymphocytes, T lymphocytes and Natural killer cells.Mac Burnet and Clonal selection theoryIn the 1950s, Mac Burnet formulated “clonal selection theory” to explain why a person produces antibodies against only those antigens to which he or she has been exposed.They produced monoclonalantibody successfullyCesar Milstein Niels Kaj Jerne Georges J. F. KohlerHumanized lymph was used to prevent smallpox in Ming dynasty in ChinaMedical immunologyMajor contents*Components and functions of human immunesystem*Rules and effects of immune response*Immune associated disease*Immune associated diagnosis and preventionCompositions ofimmune system1. Immune organs* central immuneorgans* peripheral immuneorgans2. Immune cells3. Immune moleculesimmune system（IS）Immune cellsAll the cellular elements of the blood, including the cells of the immune system, arise from pluripotent hematopoietic stem cells in the bone marrow.Membrane molecules onimmune cellsresting cells activated cellsThe expression ofimmune molecules isvariable andregulable.CKR CRcomplement cytokine Soluble immune moleculesFunctions of immune system1.Immune homeostasis2.Immune surveillance3.Immune defense1．immune homeostasis* to recognize self from non-self and keep immune homeostasis by regulatory network.* Abnormal→autoimmune disease2. Immune surveillance* to survey constantly for neoplastic cells and destroy them.* Abnormal→tumor or sustained virus infection3. Immune defense* to exclude invading organisms* Abnormal→Hypersensitivity or immunodeficiencyThe perfect worldThe real worldImmune response •Response we make against infection by potential pathogens,which is carried out by immune system.•Innate immune response,innate immunity：which is always immediately available to combat a wide range of pathogens but does not lead to lasting immunity and is not specific for any individual pathogen.•Adaptive immune response:a specific immune response, such as the production of antibodies against a particular pathogen or its products.It is developed during the lifetime of an individual as an adaptation to infection with that pathogen.It also results immunological memory,which confers lifelong protective immunity to reinfection with the same pathogen.Innate immune response and adaptive immune responseCharacters of adaptive immuneresponseThe first encounter with an antigen produces a primary response.The second or more times encounter with an antigen produces a secondary response.* appropriate response→defense infection* higher response→hypersensitivity* lower response→immunodeficiency diseasediseaseAutoimmune disease：Rheumatoid ArthritisSystemic lupus erythematosus (SLE)“Bubble boy”Severe combined immunodeficiency。