Test 4 Flashcards
Steps in phagocytosis
- WBC find target by taxis
- Pseudopods surround particle and form a phagosome (the pouch formed when the particle is brought in)
- Fusion of phagosome + lysosome = phagolysosome
Phagolysosome
Fusion of the phagosome and the lysosome
-Where digestion of ingested materials occurs.
What happens after phagocytosis
Unique and recognizable parts (antigen) are processed and placed on the phagocytic cell surface. The WBC’s then show the level 3 defenses the antigen and they know who they need to look for.
*level 3 cells only recognize antigen when placed on a WBC surface
MHC-2
Major Histocompatibility Complex, which is the holder of the antigen.
Once a phagocytic WBC has an antigen on it what is it called
Antigen Presenting Cell (APC)
-cell has officially changed roles and will travel to lymph nodes and present antigen to level 3 cells.
APC is the ____ of all level 3 responses
Activator
Examples of bacterial antigens
- Cell wall/membrane
- Exoenzymes and exotoxins (proteins)
- Flagella, pili, or fimbrae
- Capsule or glycocalyx
Viral antigens
- Capsomeres
- If enveloped virus: peplomers
- Tegument
- Enzymes
Fungi/worms/protozoa antigens
- Cell surface protein
- Enzymes
Antigens
- Usually parts of proteins (complex)
exceptions: glycoproteins - Proteins on surfaces of abnormal “self” cells are also antigenic
Inflammation
Non specific process triggered by any damage to tissues (basophils and mast cells are the cells that respond)
Inflammation response
Release: Histamine, prostaglandins, leukotrienes, stored inside cells to have a local effect on capillaries.
What do the chemicals released due to inflammation cause?
-Increase arteriole dilation and increased capillary permeability
What is the leaving of blood from blood vessels called
Diapedesis
Result of inflammation
Number of level 2 cells increases in the tissue
Resulting signs of inflammation - latin and english
Rubor - Redness
Calor - Heat
Tumor - Swelling (accumulation of fluid and cells)
Dolor - Pain, due to increased pressure on nerve endings
Acute inflammation
Damage to tissues with good response of delivering white blood cells where they are needed
Chronic inflammation
Can cause actual damage to own tissues
Natural Killer Cells
- Come from T cell line
- Wandering WBC’s
- Use perforin to make pores
- Also use granzyme to trigger apoptosis to kill abnormal eukaryotic cells
- non-specific and destroy anything exhibiting abnormal behavior such as cancerous cells, infected self cells, protozoa/yeast
*protozoa/yeast = too large to phagocytize so once apoptosis happens, leftover pieces can be phagocytize and then APC’s can be made
Granzyme
An enzyme that causes spontaneous apoptosis to kill abnormal EUKARYOTIC cells
Interferons
- Released by infected cells to tell neighboring cells to be careful
- neighboring cells produce anti-viral proteins ahead of time (thanks to the warning from the interferons)
- Neighboring cells are thus protected from viral attack which slows down the viral passage
Complement proteins
- Created by liver and secreted into the blood
- Triggered to bind sequentially to form enzymes
- Level 2 trigger: pathogen molecule (esp. LPS in Gr- or capsule in Gr- and Gr+)
- -non specific (any Gr- or Gr+ or Gr+ with capsule)
Once complement proteins are triggered what are the results?
- Phagocytosis
- Inflammation
- Membrane attack
What do complement proteins enhance?
- Phagocytosis (opsonization) - helps get rid of small yeasts and bacteria..gives the WBC’s something to grab on to.
- Inflammation - complement proteins stik on tissues causing inflammation w/o tissue damage
- allows more phagocytes/killer T cells - Membrane attack complex - proteins form a channel in abnormal cells
- cell contents leak out causing lysis and cell death