15.3/17.4/15.4 Flashcards
What are adhesins?
Proteins that aid in attachment to host cell receptors
Where are adhesins most commonly found?
Fimbriae or pili
T/F Adhesins can be universally used and don’t have specificity
F
What is it called when bacteria is in blood?
-bacteremia
What is it called when viruses are in the blood?
vieremia
What is it called when toxins are in the blood?
toxemia
What is it called when bacteria is present and multiplying in the blood?
Septicemia
What are extracellular enzymes used to host tissues called?
Exoenzymes
What exoenzymes degrade hyaluronic acid that cements cells together to promote spreading through tissues? Example: Hyaluronidase S in S. aureus
Glycohydrolases
What exoenzymes degrade DNA released by dying cells (bacteria and host cells) that can trap the bacteria, thus promoting spread? Example: DNAse produced by S. aureus
Nucleases
What exoenzymes degrade the phospholipid bilayer of host cells causing cellular lysis, and degrade the membrane of phagosomes to enable escape into the cytoplasm?
Phospholipases
What exoenzymes degrades collagen in connective tissue to promote spread?
Proteases
What are biological poisons that assist in ability to invade and cause tissue damage?
Toxins
What category of toxin can be defined as lipopolysaccharides that triggers host inflammatory responses; can cause sever fever and shock?
Endotoxins
What type of toxin can be defined as proteins mostly produced by Gram (+); targets receptors on specific cells
Exotoxins
What uses blood cells of a horseshoe crab mixed with a patient’s serum; observed chromogenically or by coagulation? What does it detect?
Limulus amebocyte lysate (LAL) Test; endotoxin
What uses antibodies to detect endoxins?
ELISA - enzyme-linked immunosorbent assay
What is intracellular targeting?
a category of exotoxin with A and B regions for activity and binding
What is called when the subcategory of exotoxins are phospholipases that degrade bilayer membrane
Membrane-disrupting
What can Hemolysins and Leukocidins do and what are they?
Membrane-disrupting exotoxins that can target RBC, WBC, and other cells
What triggers the excessive production of cytokines by immune cells? What are examples of this?
Superantigen; S. aureus and Toxic Shock Syndrome
What are these examples of:
- Capsules that enlarge bacterial cells so phagocytes cannot engulf pathogens
- Proteases digest host antibody molecules
Host evasion
What is antigenic variation?
Alteration of cell surface to hide from immune cell recognition
What is antigenic drift and shift a virulence of?
A virulence factor for viruses
What virulence in viruses are point mutations causing slight changes in spike proteins (H and N)?
Antigenic drift
What virulence in virus are major changes in spike proteins due to gen reassortment?
Antigenic shift
What virulence properties do bacteria and viruses have in common?
Adhesins and antigenic variation
What virulence properties do Fungi and Bacteria have?
Adhesins, exoenzymes, and toxins
What are produced by Claviceps purpurea and Aspergillus spp. that contaminate grains and other staple crops
Mycotoxins
What virulence properties do Protozoans and Bacteria have in common?
Adhesins, toxins, antigenic variation, etc.
Which virulence factor is this?
- Plasmodium Falciparum quickly changes adhesive protein for RBCs to avoid immune recognition; causes chronicity in malaria patients
Antigenic variation
What is Glycan gimmickry and what uses this type of method?
mimic host cells to evade the immune system; host evasion that helminths use
How is diapedesis intitiated?
Complement factor 5a and cytokines
What is the process of leukocytes passing through capillary walls to tissues?
Diapedesis/extravasation
What is the process of flattening out and squeezing through cellular junction after “rolling adhesion”?
Transendothelial migration
What does PAMPS represent?
Pathogen-associated molecular patterns; for auto recognition
What can peptidoglycan, LPS, Flagellin, Microbial DNA/RNA, and lipopeptides be examples of?
PAMPs
What are the structures that allow phagocytic cells to detect PAMPs?
Pattern recognition receptors (PRRs)
What binds to PAMPs and communicates with phagocyte nuclease to elicit a response?
Toll-like receptor (TLRs)
What can PRRs on macrophages also respond to?
Chemical distress signals from damaged or stressed cells; inflammatory response
What happens when PAMP is recognized
Phagocyte activates genes for phagocytosis, cell proliferation, interferon production, and/or cytokines
Order the phagocytosis stages in the right order?
- Expulsion of debris
- Formation of phagosome
- Formation of phagolysosome and pathogen particle degradation
- Pathogen engulfment (phagocytosis)
