Assigned animations Chapter 14 ALL:Antiviral activity of Interferon- Presence of viral material in cell  signals to produce interferon- Interferon leaves cell  attaches to receptors of cells nearby & same type- Cell now infected by virus and release more viruses to infect nearby cell- Nearby cell has interferon  can make enzyme to degrade mRNA and prevent protein synthesiso Virus can enter cell – but viral replication preventedActivation of Complement- Complement = serum protein o Activates inflammation, causes cell lysis and participates in opsonization - C1-C9 = major componento Name by order discover, not which they function- Compliment cascade activated by classical pathway or alternative- Classical pathwayo C1 activated when binds to antigen antibody complexo C1 cleave c2 into c2 a & bo C4 into c4a & bo C2b andc4b = protease  C3 convertase – cleaves c3 into c3 a & b- Alternative pathwayo Atigens react with C3bo C3a & b are formed from C3 w/o activation = destroyedo C3b reacts with proteins factor b and factor d and properdin = form C3 convertase- Both pathways follow same sequence after cleavge of C3- C3 – stimulates inflammation - Microorganism with C3b bound to surface are more susceptible of phagocytosis- Coding of bacteria to make them more susceptible to phagocytosis = opsonization- C5 a = enhances inflammation- C5b reacts with other to form membrane attack = causes hole and cell to lyseFunctions of Complement- C3a = inflammationo Induce change to walls of vessel- C5a = attraction of neutrophilso Induces chemotactic migration of phagocyte to site of complement activation - C3b = opsonizationo Binds to microbial cells making them more susceptible to phagocytosis - C5b. C6, C7, C8, C9 = cell lysiso Makes hole in cell membrane = lysis Toll-like receptors (to give an overview, above your paygrade info)Phagocytosis- Attracted by chemical product of organism 1- Phagocyte attaches to microorganism from surface receptors  antibodies, lipopolysaccharide and complement receptors- Microorganism engulfed by phagocyte into vacuum = phagosomeo fuses with lysosome  releases digestive enzymes ito phagosome = phagolysosome inside, microorganisms are killed and digested digested contents are eliminated via exocytosis-Lysosomes- Lysosomes = membrane bound vesicles that can contain hydrolytic enzyme- Hydrolytic enzymes degrade proteins, lipids, nucleic acids, and carbso Formed in ER- Enzymes transported to golgi app via transport vesicles- When viruses/bacteria are ingested, lysosome fuses with phagosome – delivers hydrolytic enzymes- Lysosomes also fused with organelles like old mitochondria – helps with destruction and recycling of structuresThe Inflammatory process - Response in a non-specific defense against tissue damage- Begins when chemical singals activate endothelial cells of nearby capillaries - Integrins attach to endothelial cells – cause neutrophils to stick and stop roling o Accumulation of neutrophils along walls of capillary = margination - Histamine = causes vasodilation and an opening btw junction of endothelial wall I. The Immune System: There are two basic arms of the immune system:A. Acquired Immunity  specific immune system 1. Also called cognate immunity because it is a learned response. We are exposed to the specific microbe and the acquired immune system will learn to recognize it and respond to it. a. Example, we have measles when we are children, but our immune system learns to identify that specific pathogen and is ready for subsequent exposures. b. It has acquired the ability to recognize that pathogen.c. Takes time to be initiatedd. Knows and recognizes specific pathways1) Knows the antigen it is fighting off e. How quickly can one bacteria become 16 mill?1) 8 hours2) If we have to wait a week, we just use the innate immune system 2. Very specific, but it takes time to become activated, not just hours, but days.a. Needs to build an “army” to fight off infection B. Innate immunity  natural immune system 21. It is the first line of host defense, typically works by blocking the invasion or the invasive properties of the microbe or its replication. 2. You acquire it at birth-or they are things that come with our body.3. You don’t have to have previous exposure to an organism to have this type of immunity.a. Function of the immune4. Quick response 5. Does not know specificity II. Overview of natural immunity or the rapid response immune system (Fig. 14.1)A. First line defenses = WALL1. Defense System (Fig. 14.1)a. Epithelium (Fig 14.2, 14.3, Ch. 22.1)1) 2 forms2) Stratified squamous epithelium - Basal cells are stem cells that constantly divide. Overlapping epithelial cells that become keratinized as they move towards the surface to waterproof the surface of our body.- Have a thick layer - On the outside of the body- Cuboidal epithelium – stem cell at the bottom1. Continually Grow and divide – nucleus is lost, and cell is no longer alive 2. Initiates keratin – water proofing molecule3. Just have dead skin on surface – viruses cannot replicate in dead cell- Tight junctions hold cells together 1. Keeps normal microbiota from coming in - 3rd degree burn – have burned of cuboidal and now into the epidermis - In epidermis – have basal cuboidal cells- Thick wall that does not allow anything in b. Mucous membranes  only one layer thick 1) Ciliated stratified/pseudostratified columnar epithelium- Most important  ciliated epithelium = what helps absorb nutrients in your guts- One layer thick1. Nucleus is fat2) Mucous made by goblet cells in ciliated columnar epithelium- Want mucus to be thick and sticky so that when you breath in a virus, it’ll get trapped into sticky mucous and pushed into the acid in the gut 3) mucociliary escalator: cilia moves the mucous along- ways to get rid of things trapped in mucous:1. Ingestion - cilia sweep it to the stomach where the acids there destroy it.a. Swallowing 2. Expulsion- sneezing, when we breathe something in that the body wantsto let out immediately 34) Problems- Some bacteria actually like mucous membranes. 1. Ex: syphilis 2. Keeps them from drying out – keeps it moist to survive - Winter environment1. Dry, stale winter air reduces viciousness of mucous 2. Diseases due to breaks in the skina. Break in barrier of epithelium=infection  allow microbes in b. Chronic obstructive pulmonary disease (COPD)  chronic and it obstructs pulmonary function