Chapter 11 Flashcards
Immune response
physiological process by the “immune system” to get rid of antigens
Antigen
Any substance that, if presented in the right context, may trigger an immune response
Mostly proteins or polysaccharides that come from a bacterium, virus, fungus, or protist
Innate Immunity
Inborn ancient protection existing in one form or another in all eukaryotic organisms
Generalized responses
Non-Specific immunity
Adaptive immunity
Only in vertebrate animals
Matures over time
Responses tailor to pathogens
4-7 days to full activate
Exhibits memory
Immune
Specific protection conferred by adaptive immune responses
Susceptible
Not immune to a given pathogen and it may cause infection
First-line defense
attempt to prevent pathogen entry, make sure they don’t get in
First-line defense types
Mechanical
Chemical
Physical
Mechanical barriers
trap pathogens to limit their spread into body
tears, urine, saliva, mucus membranes
Chemical barriers
Directly attack invaders or establish environments that limit pathogen survival
Stomach acid, lysosomes in tears, breast milk, mucus
Physical barriers
Structures that physically block pathogen entry
Skin
Second-line defense
When the pathogen does inevitably get into the body
includes leukocytes and any other molecular factors
Lymphatic system
Collect, circulate, and filter fluid in body tissues before it is returned to the blood
Primary lymphoid tissues
Site of production and maturation of leukocytes
Thymus and bone marrow
Secondary Lymphoid tissues
Filter lymph
Lymph nodes, spleen, and mucosa-associated lymphoid tissue (MALT)
Thymus
Site of T cell maturation
Bone marrow
main site of red/white blood cell production
Lymph nodes
serve as a filtering and screening centers for lymph before returning to the blood
Spleen
Place where leukocytes look for invaders
Filters blood rather than lymphatic fluid
MALT
Diffuse system of lymphoid tissue
Granulocytes
cells with granules in cytoplasm when stained
Agranulogytes
cells with no granules in cytoplasm
Natural killer cells
Abundant in the liber
Innate protection against viruses, bacteria, parasites and even tumor cells
T and B cells
Coordinate the adaptive immune response
WBC differential
Determines if any leukocytes are over or underrepresented in a patient’s blood Gives insight to what the body might be responding to
Leukocytosis
increase in leukocytes
Cytokines
Signaling proteins that allow cells to communicate with each other
Chemokines
specific cytokines, attract WBCs to areas where they’re needed
Chemotaxis
movement of motile cell or organisms in a direction corresponding to gradient of increasing or decreasing concentration of a particular substance
Interleukins (ILs)
Activate adaptive and innate immune responses
Interferons (IFNs)
Signaling molecules
Signal when pathogens or tumor cells are detected
Iron-Binding Proteins
Iron is a vital nutrient for most cells
Ex. hemoglobin
Iron-Binding Proteins: Pathogen methods
Siderophores – organic molecules that pull iron from our iron-binding proteins
Hemolytic bacteria – break down red blood cells to get to the iron-rich hemoglobin inside
Inflammation
Important part of our innate immune defense and is essential to healing
Tissue injury initiates blood-clotting cascades
Blood clots curb blood loss and limit pathogen spread
Problems with inflammation
but if unregulated it starts to damages our own tissues
Main goals of inflammation
Recruit immune defenses to injured tissue
Limit spread of infectious agents
Deliver o2 nutrients and chemical factors for tissue recover
Signs of inflammation
Redness
Pain
Localized heat (not fever)
Swelling
Loss of function
Chronic Inflammation
When inflammation goes on for too long
Not useful or protective
Exacerbates tissue injury
Could cause certain disorders
Fever
Abnormally high systemic body temperature
Pyrogens
fever-inducing agents
Trigger the release of cytokines that signal the hypothalamus to raise the body’s baseline temp
Levels of fever
Low-grade: 37.5°C to 38.3°C (99.5–101°F), Considered protective
Life threatening: 40.5°C (105°F)
Fatal: 43°C (109.4°F)
