Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/54

Click to flip

54 Cards in this Set

  • Front
  • Back
What mediates the activation of complement proteins of the immune system?
Microbial surfaces or by antibody-antigen complexes.
What are the three complement activation pathways?
1. Classical
2. MB-Lectin
3. Alternative
In classical activation pathway, what causes C1s to become an activated enzyme?
Binding of C1q, C1r, and C1s to antigen and IgG (or IgM)
In classical activation pathway, what does C1s active enzyme do?
Cleaves C2 in to C2a and C2b.
Cleaves C4 in to C4a and C4b.
In classical activation pathway, what cleaves C3?
C4b2a enzyme
What is the C3 convertase in Classical activation pathway?
C4b2a
In classical pathway, what happens to C3 convertase after it cleaves C3?
Binds with C3b to form C4b2a3b.
In classical pathway, what does C4b2a3b do?
Cleaves C5 into C5a and C5b
What is similar about all three pathways?
C5b will recruit C6, C7, C8, and C9 into a self-assembled complex. C9 of this complex will "drill" a transmembrane pore inducing cell lysis.
In classical pathway, what is the C5 convertase?
C4b2a3b
In classical pathway, what is required?
Antibody (acquired immunity)
In MB-lectin pathway, what is initially required?
A mannan-binding lectin must bind to a mannose on microbial surface.
In MB-lectin pathway, a complex of mannose and MB-lectin leads to what?
Binding of MASP I and MASP II.
In MB-lectin pathway, what do the MASP's do?
Cleave C2 (into C2a and C2b) and C4 (into C4a and C4b)
In MB-lectin pathway, what happens after MASP cleavage?
Formation of C4b2a
In MB-lectin pathway, what is the C3 convertase?
C4b2a
What does the C3 convertase do and what is the final product in the MB-lectin pathway?
C3 convertase cleaves C3 into C3a and C3b. This forms C4b2a3b.
In MB-lectin pathway, what is the C5 convertase?
C4b2a3b
In the alternative pathway, what must occur initially?
Slow spontaneous hydrolysis of the thioester in C3.
In the alternative pathway, what happens after C3 is hydrolyzed?
Factor B comes in and gets attached.
In the alternative pathway, what does Factor D do and what is the resultant product?
Cleaves Factor B on the C3B complex to Ba and Bb. This results in C3Bb complex.
In the alternative pathway, what is the C3 convertase?
C3bBb
In the alternative pathway, what happens to C3Bb and what is the result product?
Cleaves the C3 on itself into C3a and C3b leading to the formation of C3bBb
In the alternative pathway, what is the event immediately following formation of C3bBb?
C3bBb forms many molecules of C3b which attach to the microbe.
In the alternative pathway, what does C3bBb bind to?
An additional C3b to form C3bBb3b.
In the alternative pathway, what does C3bBb3b bind to?
Factor P
In the alternative pathway, what is the C5 convertase?
C3bBb3bP
Describe the properties of C5a
Vasoactive and chemotactic properties.
Describe the properties of C3a.
Increases vasodilation and vascular permeability contributing to inflammation
In the MB-lectin pathway, what is the stabilizing event?
The binding to microbial surfaces.
In the alternative pathway, what is the stabilizing event?
Factor P (properdin) binding to C3bBb3b.
How is systemic activation prevented in the complement pathways?
As activated components move farther ways from sites of activation, they are more likely to be susceptible to inhibitors.
What can be said about disorders of complement proteins?
Very rare.
What is the difference between primary vs secondary immune deficiency diseases?
Primary's are congenital and secondary's are disorders associated with induced molecules or cells such as complements.
List three classes of lipid mediators derived from arachidonic acid.
1. Prostaglandins
2. Leukotrienes
3. Thromboxanes
NSAID's inhibit what precursor of what lipid mediator(s)?
Inhibits cyclooxygenase thus inhibiting prostaglandins and thromboxanes
Effects of prostaglandins. x 3
1. Increase vasodilation
2. Increase vascular permeability.
3. Increase pain perception
Effects of thromboxanes x 2
1. Increases platelet aggregation
2. Increases vasoconstriction
Effects of Prostacyclins x 2
1. Inhibits platelet aggregation
2. Increases vasodilation
The peptide, Bradykinin, causes what in what condition?
Mild inflammation in the absence of infection.
What is the peptide, Bradykinin, activated by?
Blood clotting.
Bradykinin acts through what receptors?
B1 and B2 receptors.
What are the vascular effects of Bradykinin?
1. Increase vasodilation
2. Increase vascular permeability.
What are the effects of serotonin and histamine? x 2
1. Increase vasodilation
2. Increase vascular permeability
Where are serotonin and histamine derived from? x 4
Basophils
Eosinophils
Mast cells
Platelets
What does nitric oxide increase in responsive cells?
cyclic GMP
Nitric Oxide is produced by three enzymes. Name two.
1. iNOS (NOS1)
2. eNOS (NOS3)
Where is iNOS made and what does it do?
Made in macrophage and produces anti-microbial effects.
What is eNOS and what does it do?
Endothelial NO synthase. Increases vasodilation and increases vascular permeability.
Are cytokines local or systemic?
Local
What do cytokines do in general?
Act on receptors to alter cell function
Constituitively expressed chemokine receptors generally involved in what?
Trafficking
Inducible chemokine receptors involved in what?
Inflammation
What are the co-receptors of HIV-1? x 2
CCR5 and CXCR4