Biology M2001st Edition Lecture 13Outline of Last Lecture I. Innate Immunitya. Species ResistanceII. Complement SystemOutline of Current Lecture I. AntigensA. Exogenous, Endogenous, and Auto-antigens.II. Antibodiesa. Antibody functionsIII. Lymphatic SystemCurrent LectureI. Antigensa. Exogenous antigens: microbes (or part of microbes) that originate outside the body’s cells.b. Endogenous antigens: generated within a previously normal host cell.i. Fragments of the microbe are displayed on the surface of the host cells.c. Auto-antigens: Found on normal, uninfected host cells.i. Immune cells that recognize auto-antigens have to be purged.II. Antibodiesa. Definition: proteins (adaptive immune system) with ANTIGEN-BINDING SITES thatbind to the epitopes on antigens.b. Functions: Neutralization, Opsonization, Oxidation, Agglutination, and Cellular cytotoxicity.III. Lymphatic Systema. Form a one-way system that returns fluid from body tissues to the circulatory system.b. Lymph: a fluid leaked from blood vessels into surrounding tissues (may carry antigens)c. B lymphocytes (B cells)i. A type of leukocyteii. Arise and mature in the bone marrowiii. Found primarily in the lymph nodesThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.iv. Secrete antibodiesv. Have receptors that can recognize millions of different epitopes and generate antibodies against them. vi. Plasma Cells: make up the majority of B lymphocytes1. Each plasma cell secretes antibodies complementary to specific epitope.2. Short-lived cells: die within a few days of activation, though their antibodies and progeny can persist.vii. Memory B Cells: do not generate antibodies1. Have receptors complementary to the specific antigen that triggered their production.2. Long-lived cells: divide only a few times, then persist in the lymphoid tissue. d. T lymphocytes (T cells)i. A type of leukocyteii. Arise in bone marrow, mature in thymusiii. Circulate in the lymph and bloodiv. Have receptors (TCRs) that bind to antigensv. Cytotoxic T Cells: directly kills infected human cells, secrete perforin and granzyme to kill infected cells. IV. Acquired Immunitya. Naturally acquired: immune response against antigens encountered in daily life.b. Artificially acquired: response to antigens introduced via a vaccine or antiserum.V. Immunizationa. Active immunization: administration of a vaccine so that the patient mounts a protective immune response.b. Passive immunization: transfer of antibodies formed by an immune individual or an animal confers