Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Immunology > B cell activation #2 > Flashcards

B cell activation #2 Flashcards

1
Q

What is allelic exclusion?

A

one allele of a gene is expressed while the other is silenced (It makes one LC + one HC)

Without it you will have Ab with multiple specificities.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is heavy chain rearrangement?

A

@ B cell
Heavy chain –> is productive –> could be maternal mui or paternal mui

if second time doesnt work: apoptosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is light chain rearrangement?

A

@ Pre- B cell

Heavy chain –> isnt productive –> made again
Can be rearranged x4
paternal: kappa + mui
maternal: kappa + mui

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is isotype switching?

A

Changing from IgM to another isotype (IgE + IgA + IgG)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Does switching isotypes change specificity?

A

No (even if you rearrange it can bind to what it needs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does isotype switching need?

A

switch regions + T helper cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where does isotype switching take place?

A

germinal centers of secondary lymphoid organs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What enzymes needed for isotype switching?

A

AID –> activation-induced cytidine deaminase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where is the switch region found?

A

in front of mui + in front of gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why is there no switch region in front of delta?

A

Because when making mui you need delta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 2 T cell signals needed to get cytokines for isotypes?

A
  • SIGNAL 1: MHC signaling with APC B cell

* SIGNAL 2: CD28 – B7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What cytokines released to make IgG?

A

IFN gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What cytokines released to make IgE?

A

IL4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What cytokines released to make IgA?

A

Tgf-beta/APRIL/BAFF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is diversity generated?

A

Random assortment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are examples of diversity? (3)

A

Permutations in V-D-J genes for H.C and V-J genes for L.C. (You have rearrangement of heavy + light chains)

Pairing of different H.C. and L.C.

Recombination process by imprecise joining  junctional diversity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is junctional diversity?

A

Joining of V,D and J (small no. nucleotides can be added/ deleted)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is somatic hypermutation?

A

Mutations that occur in the V, D or J segments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the affinity maturation in primary + secondary response?

A

o Primary response: Antibodies have a lower affinity
o Secondary response: there is somatic hypermutation and affinity maturation which means= > Ab + Ab has higher affinity for antigen

20
Q

What segments are found in alpha, gamma, delta and beta TCR?

A

Alpha + gamma: VJC

Delta + beta: VDJC

21
Q

How is alpha chain made?

A
  • Joining: V+ J joining
  • Transcription -> Primary RNA transcript made
  • Splicing -> mRNA made
  • Joining: VJ put together + C
  • translation
  • Then protein made: alpha chain
22
Q

How is beta chain made?

A
  • Joining: V+ J joining
  • VDJ formed
  • Transcription -> Primary RNA transcript made
  • Splicing -> mRNA made
  • Joining: VDJ put together + C
  • translation
  • Then protein made: beta chain
23
Q

What is immunization? And how do we do it?

A

Provide individual with long-lasting immunologic protection again infectious agents

They slightly from infected -> put in healthy -> immunity (slightly infected called Inoculated)

24
Q

What is components of natural acquired passive immunity?

A

IgG –> placenta
IgM –> after birth
IgA -> breast milk
IgG > as we grow + IgA (

25
Q

What is artificially acquired passive immunity?

A

Ig/ immune cells (based on MHC) -> injected artificially

26
Q

is artificially acquired passive immunity Injected pre/post exposure? What are examples of artificially aquired passive immunity?

A

Post exposure

Diphteria + Tetanus + Measles + Rabies

27
Q

What type of hypersensitivity is artificially acquired passive immunity?

A

3

28
Q

What is the benefit of artificially acquired passive immunity?

A

Immediate protection

29
Q

What is the disadvantage of artificially acquired passive immunity?

A

o no long term production + chance of serum sickness (immune system react to foreign proteins -> immune complexes)

o Donors must be properly screened: HIV + hepatitis

o Graft versus host disease when immune cells are injected

30
Q

Describe + give examples of this active immunization: Killed whole organism

A

Entire organism -> killed to be harmless

example: typhoid

31
Q

Describe + give examples of this active immunization: Attenuated bacteria

A

Culture organism to reduce pathogenicity but retain antigen of virulent form
example: Tuberculosis

32
Q

Describe + give examples of this active immunization: toxoids

A

Bacteria toxins proteins denatured -> no longer dangerous -> has epitopes for protective antibodies
example: Diphtheria + tetanus

33
Q

Describe + give examples of this active immunization: Surface molecules

A

Purified surface molecules isolated from various pathogens

example: Influenzas + hepatitis B + S. pnemonia

34
Q

Describe + give examples of this active immunization: Inactivated virus

A

Virus treated so it wont infect host cell -> has epitopes for protective antibodies
example: Salk vaccine for polio

35
Q

Describe + give examples of this active immunization: Attenuated virus

A

Live viruses weakened to be nonpathogenic

examples: Polio vaccine + measles + mumps + rubella

36
Q

Describe + give examples of this active immunization: recombinant virus proteins

A

Major capsid proteins

HPV + hepatitis B

37
Q

What are live vaccines?

A

attenuated organisms –> These organisms are able to cause mild undetectable infection but not disease

38
Q

What is the immune response in live vaccines? What is the dosage?

A

Immune response: Immune response similar to natural infection
Dosage: One dose is effective except in those administered orally

39
Q

What is the disadvantage of live vaccines?

A

o virulent: The organism may mutate & revert to virulent form + severe reactions possible
o Cause disease: Risk of causing disease in immunocompromised persons
o Pregnancy: May cross placenta & damage foetus: Should be avoided in pregnancy
o Temperature: Must be kept at optimum temp from production to use (cold chain)

40
Q

What are adjuvants? What are adjuvant examples?

A

Weak antigen + adjuveant -> make it more immunogenic

Adjuvant example: Aluminum salts (alum) is approved in humans

41
Q

What are the immune responses to vaccines: Live attenuated vaccine ?

A

CD8+ & CD4+ & B cells

42
Q

What are the immune responses to vaccines: inactivated vaccines?

A

B cells & CD4 T cells

43
Q

What are the immune responses to vaccines: Polysaccharide vaccines induce only B cells without the aid of CD4 positive T cells ?

A

T- cell independent immune response (repeated on surface) + primary + secondary response is the same. (NO MEMORY)

44
Q

What is idiotype?

A

the distinctive sequence and region that makes any immunoglobulin/TCR unique from others of the same type (which is its variable region.)

45
Q

What is allotype?

A

each immunoglobin has unique sequences particular to the individual’s genome that manifest in its constant region

46
Q

What is isotype?

A

refers to the slight phenotypic variations within the immunoglobulin gene family that encode for variant immunoglobulin heavy chains and immunoglobulin light chains.

Immunology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions