First Line of Defense
Skin, Mucous Membranes, Normal Flora
Two layers, Epidermis and Dermis
top layers of dead cells tightly packed
contains collagen which PREVENTS deep cuts
3 things the skin releases onto its surface...
Salt osmosis, lysozyme, sebum
water out of bacteria, keeps bacteria from growng except staph.
destroys cell walls of bactera.....cellysis.
its oily and keeps pH to around 4 and inhibits bacteria.
continually shed and are replaced.
2 Layers of mucous Membranes
epithelium and a connective tissue layer.
Mucous membranes in Trachea
have goblet cells and ciiated columnar cells.
secrete sticky substance (mucous)
Ciliated columnar cells
have cilia, mucous that push pathogens out.
Mucous membranes have
lysozyme in mucous. Eyeballs and spit.
protects and acts as a microbial antogonism.
1. protects the body by competition. 2. Limits growth of pathogens. 3. Consume nutrients. 4. Controls pH.
Second line of defense
cellular. White cells. Leukocytes.
Large granules in cytoplasm. 1 Neutrophil 2. Basophil 3. Eosinophils
Pyagocyte. PMN-polymorph nucleocyte. Most common WBC. 60-70% with a pH 7 inside cell (named Neutrophil) All will have different shaped nucleus.
NOT a phagocyte. Good for parasite infections (worms) 0.5-1.0%. CAUSES allergies. a type one hypersensitivity. Cant see nucleus. Acidic inside, use basic stain.
Phagocyte. CAUSES allergies or type one hypersensitivity. Are basic inside and use eosin to stain. They travel around the body and gobble up stuff. 2-4%
Without granules. Lymphocytes and Monocytes. And specialized cell called Dendritic.
Agranulocytes. Mostly specific immunity except the NK lymphocytes. (Natural Killer)
Agranulocytes. Unspecific immunity. Take over job when T cell can't do it. Look for and kill cells that are infected with viruses or that have cancer.
Agranulocytes. Give off antibodies.
Agranulocytes. Either activates immune system or kill cells with viruses or cancer. Look for and kill the cells that are infected with viruses or that have cancer. CANNOT be killed by T-cells.
Mono meaning blood and Macro meaning in tissue. Are phagocytes and APC. (antrogen producing cell) can't wonder.
Agranulocytes. Phagocyte, multi branched cells are scattered throughout the body particularly in the skin and mucous membranes where they wait for microbial invaders. Named for teir resemblances to neuron. Most efficient antigen trapper and the most efficient APC. Best phagocytes and the BEST ANTROGEN PRODUCING CELL.
scavengers, travelers, some do not wander.
Phagocytosis in 5 steps..
1. Chemotaxis 2. Adherence 3.Ingestion 4.Digestion 5. Elimination
Movement because of a chemical stimulus from 1. Microbial waste products 2. Damaged tissue 3. Cytokines (special protein signals).
1. Bind through complementary proteins (glycoprotein) found on cell membranes of pathogens. 2. Opsonization-coating process with proteins that aid in adherence. Abs and complement.
1. Phagosome fuses with Lysosome=phagolysosomes. 2. Digestive enzymes 3. Toxic oxygen derivatives (super oxides that WBC make) like free radicals and hydrogen peroxide. 4. After digestion it is a residual body.
Elimination or put on MHC
Exocytosis----reverse of ingestion.
Non-specific Chemical Defenses
Complement chemical, cytokines, interferons, fever caused by IL-1,
Serum proteins designated numerically according to the order of their discovery.
1. Opsonins 2. Chemotactic factors call more phagocyte to the area 3. Cell lysis, made in liver floating in the blood.
call more phagocyte to the area.
Classical pathway mechanism
antibodies activate complement.
pathagens or pathogenic products such a bacterial endotoxins and glycoproteins activate complement. Starts with the other half of C3. 1. NO antibody binding needed. 2. C3b binds to glycoproteins on the sureface of a bacteria or a fungus. 3. C3 binds to Properdin factors. 4. Splits more C3 molecules. 5. Activates the complement cascade (same process over) 6. Inflammation 7. Membrane attack complexes.
Classical pathway mechanism or the Alternate pathway
Alternate pathway steps
1.No antibody binding needed 2.C3 binds to glycoproteins on the surface of bacteria or a fungus.3. C3b bingd to Properdin actors 4. Splits more C3 molecules 5. Activates the complement cascade. (opsnization and dell lysis again, same process over) 6 Inflammation 7 Membrane attack complexes(receptors, pores or channels)
Other chemicals in the body for different functions. 1. small proteins 2. Cell to cell communication 3. Serve as chemical communicatiors that release chemicals.
IL-1 IL-2 IL-3 IL-4 Tumor Necrosis Factor (TNF) , Interferons, There ar many more than this, Responsible for many functions.
Small proteins to fight a viral infection. Alpha, Beta, Gamma
Secreted by Monocytes, Macrophages and some Lymphocytes
Secreted by fibroblasts.
Secreted by T-lymphocytes and NK cells.
Actions of Alpha and Beta Interferons
a) secreted after the cell in infected with virus b) Viral infected cell is doomed c) Binds to receptors on the membrane of other cells that are NOT infected. d) Triggers production of Antiviral Proteins (AVP) inside cell and shut it down) Antiviral Proteins are activated by binding to the double stranded RNA of Viruses.
Actions of Gamma Interferons
1. Released by the activation of T-cells and NK lymphocytes. 2. Stimulates the activation of Macrophages and Neutrophils.
1. releases macrophages. 2. Raises body tempurature over 37 degrees celcius. 3. Goes along with malaise , body aches, tiredness. 4. Caused by chemicals called Pyrogens. (think pyro, heat) 5 Relesed by phagocytes and many other cell types.
IL-1 raises body tempurature
a) IL-1 stimulates the hypothalamus b) This then stimuates the body to raise the temperature c) Rapid and repetitive muscle contractions d) Shivering e) Increase metabolic rate ) Constricts blood vessels to keep the heat and blood in (makes you feel cold and clammy) g) Does all of this to raise the bodies core temperature.
a) As infection subsides b) Less active macrophages c) Less IL-1 d) Everything starts to return to normal e) Start perspiring
A fever may
1) enhance interferons 2) inhibits the growth of microorganisms 3) Enhances some parts the immune response 4) If fever gets out of control you can go into coma and death 5) Is a fever beneficial or not? NOT SURE
Another set of proteins that punch holes in membranes and cause cell lysis.
are small peptides that 1) Act against a wide range of parasites 2) Punch holes in membranes 3) Production increses ue to a response to inflammation 4) Secreted by macrophages 5) Good at fighting many types of bacterial pathogens
part of the immune response and is non-specific and can be chronic or acute.
Inflammation can be from
heat, chemicals, sunburn, cuts and abrasions, pathogens
Signs of Inflammation
redness, pain, edema (swelling) and heat in the region.
Benifits of inflamation
get increased permeability of blood vessels. More blood, more macrophages. Migration of phagocytes to the area and Tissue repair.
Mechanisms of Inflammation
Damaged cells release Histamine (causes asthma attack), Prostaglandins, and Leukotrine.
causes asthma attack.
born with it, attacks all kinds, physical barrier exam. skin