Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

1. IMMUNOSERO PRELIM > MAJOR HISTOCOMPATIBILITY COMPLEX > Flashcards

MAJOR HISTOCOMPATIBILITY COMPLEX Flashcards

1
Q

Lymphocytes can be divided into three major populations —

A
  • T cells,
  • B cells,
  • natural killer (NK)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

produce cytokines that contribute to
immunity by stimulating B cells to produce antibodies, assisting in killing tumor cells
or infected target cells, and helping to regulate both the innate and adaptive immune
response.

A

T cells

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

% of T cells

A

61-80%

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

does not directly recognize the antigens of microorganisms or
other living cells but recognizes when the antigen is present on the surface of an
antigen-presenting

A

T lymphocyte

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

10-20%: End product of activation is antibody

A

B cell

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

NK cell %%

A

10-15%

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

Referred to as HUMAN LEUKOCYTE ANTIGEN (HLA)

A

MHC Molecules

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

MHC Molecules Referred to as

A

HUMAN LEUKOCYTE ANTIGEN (HLA)

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

Molecular basis for T cell discrimination of self from non-self

A

MHC Molecules

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

Found on the SHORT ARM of CHROMOSOME 6 at BAND 21

A

MHC Molecules

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

MHC Molecules found on ?

A

SHORT ARM of CHROMOSOME 6 at BAND 21

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

Gene product of MHC molecule found in?

A

WBC

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

Allows for an IMMUNE RESPONSE to DIVERSE IMMUNOGENS

A

MHC Molecules

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

Second only to the ABO antigens influencing the survival or graft rejection of
transplanted organs

A

MHC Molecules

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

Considered the MOST POLYMORPHIC SYSTEM

A

MHC Molecules

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

different individuals have different MHC alleles resulting in immune system
recognizing variation

A

Polymorphism

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

different variations of MHC molecules

A

Alleles

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

Main Function:
* Bring antigen in the body to the surface of cells for recognition by T CELLS
* T cell activation – occur only when antigen is combined with MHC molecules

A

MHC Molecules

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

3 Classes of MHC Molecules

A
  • Class 1
  • Class 2
  • Class 3
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Class 1 Molecules Loci (Classical)

A

HLA-A
* HLA-B
* HLA-C – Not expressed in the surface of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Class 1 MHC Not expressed in the surface of cells

A

HLA-C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Class 1 MHC Non-Classical

A

HLA-E
* HLA-F
* HLA-G – expressed in trophoblast cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

HLA-G Non-Classical MHC 1 expressed in?

A

Trophoblast cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Present antigen to:
CD8+ T cells – triggering a cytotoxic reaction

A

Class 1 Molecules

25
Q

Function:
* Associate with foreign antigens, such as:
Viral proteins, tumor, parasitic antigens
Synthesized WITHIN a host cell
ENDOGENOUS pathway for antigen presentation

A

Class 1 Molecules

26
Q

Class 2 Molecules Major Class II

A
  • HLA-DP
  • HLA-DQ
  • HLA-DR
27
Q

Loci of Class 2 MHC

28
Q

Class 2 Molecules Non-Classical Class II

A
  • HLA-DM
  • HLA-DN
  • HLA-DO
29
Q

Only found on:
* B cells
* Monocytes
* Macrophages
* Dendritic cells
* Thymic epithelium

A

MHC 2 molecules

30
Q

MHC 2 molecules are only found on, what are these cells?

A

Only found on:
* B cells
* Monocytes
* Macrophages
* Dendritic cells
* Thymic epithelium

31
Q

Present antigen to:
* CD4+ T cells
helper cells involved in antibody production
regulate the interaction between helper T cells and ANTIGEN PRESENTING
CELLS

A

MHC 2 molecules

32
Q

Function:
* Associate with foreign antigens taken into the cell from the OUTSIDE
* EXOGENOUS ANTIGEN PRESENTATION

A

MHC 2 molecules

33
Q

Code for the:
* C4A
* C4B
* C2
* B complement proteins
* Cytokines
o Tumor necrosis factor

A

Class 3 Molecules

34
Q

Class 3 Molecules code for the?

A

Code for the:
* C4A
* C4B
* C2
* B complement proteins
* Cytokines
o Tumor necrosis factor

35
Q

Secreted proteins that have an immune function, but they are not expressed on cell surfaces, as
are class I and II

A

Class 3 Molecules

36
Q
  • Mainly present peptides that have been SYNTHESIZED WITHIN the cell
  • They present it to CD8+ (Cytotoxic) T cells
  • If antigens is recognized as being foreign, cytokines are released causing destruction of
    the target cell
A

Class I Restriction

37
Q

Mainly BINDS EXOGENOUS PEPTIDES
* Present these to CD4+ helper T cells which then secrete cyotkines that cause an antigen
ACTIVATED B CELL to PROLIFERATE and PRODUCE PLASMA CELLS to make
ANTIBODIES against the ANTIGEN.
* Significant in BACTERIAL INFECTIONS
* Significant in the presence of other material that is ENDOCYTOSED by cell

A

Class II Restriction

38
Q

Class I MHC Molecule Cellular Distribution

A

All nucleated cells

39
Q

Class I MHC Molecule Structure

A

One a chain and B2 microglobulin

40
Q

Class I MHC Molecule Classes

41
Q

Class I MHC Molecule Size of peptides bound

A

8-11 amino acids

42
Q

Class I MHC Molecule Nature of peptide binding cleft

A

closed at both ends

43
Q

Class I MHC Molecule Interaction with T cells

A

Presents endogenous antigen to CD8+ T cells

44
Q

Class II MHC Molecule Cellular Distribution

A

B cells
Monocytes
Macrophages
Dendritic Cells
Thymic Epithelial Cells

45
Q

Class II MHC Molecule Structure

A

A chain and B chain

46
Q

Class II MHC Molecule Classes

47
Q

Class II MHC Molecule Size of peptides bound

A

13-18 amino acids

48
Q

Class II MHC Molecule Nature of peptide binding cleft

A

Open at both ends

49
Q

Class II MHC Molecule Interaction with T cells

A

Present exogenous antigen to CD4+ T cells

50
Q

Main Role of Class I and II Antigen
Presentation

A

Bind peptides within cells→ Transport them to the plasma membrane →T cells recognize them

51
Q

Attack cells from the OUTSIDE

52
Q

Attack cells from the INSIDE

53
Q

ROLE of HLA

A

Successful organ transplant
Paternity Testing
HLA typing

54
Q

HLA typing is also useful in:

A

Forensic medicine
anthropology
Basic research in immunology

55
Q

Process of eliminating/rejecting foreign
antigen

A

APC dendritic cells → present T lymphocytes (CD4+ cells/T helper cells) → Function T helper
cells: → CD4+ cell helps CD8+ cells to destroy bacteria or antigen that are present within the
cell → stimulate B cells → B cells when activated – trigger plasma cells → plasma cells will
produce antibody → destroy bacteria

56
Q

ENDOGENOUS PATHWAY SIMPLIFIED

A
  1. Endogenous antigen within cytosol is degraded by proteasome
  2. Peptide transported into Endoplasmic Reticulum by TAP
  3. Alpha chain of Class 1 MHC binds to B2-microglobulin
  4. Alpha chain of Class 1 binds to peptide
  5. Peptide-class 1 MHC transported to Golgi Complex and then to cell surface
  6. Class 1 MHC peptide binds to CD8+ T cells
57
Q

Exogenous Pathway SIMPLIFIED

A
  1. Class 2 MHC binds invariant chain to block binding of endogenous antigen
  2. MHC complex goes through Golgi Complex
  3. Invariant chain is degraded, leaving CLIP FRAGMENT
  4. Exogenous antigen taken in and degraded and routed to intracellular vesicle
  5. CLIP fragment exchanged for antigenic peptide
  6. Class 2 MHC antigenic peptide is transported to cell surface
  7. Class 2 MHC peptide complex bind to CD4+ T cell
58
Q

Mechanism Endogenous Pathway Class 1

A
  1. Virus enters the cell and produce its own antigenic protein
  2. Antigenic protein enters proteasome
    a. Proteasomes: degrades antigenic protein into peptides
  3. In RER has attached Ribosomes
  4. Ribosomes: synthesize/produce MHC class 1 molecules (Incomplete structure only
    alpha chain; no beta 2 microglobulin)
  5. MHC class 1 will bind to Calnexin
    a. Calnexin: chaperon molecule that allows the binding of incomplete MHC 1 into
    beta 2 microglobulin
  6. After MHC class 1 is complete (binded alpha and beta 2 microglobulin) it will produce
    2 chaperon molecules which stabilizes the structure of MHC class 1
    a. ERp57 (Endoplasmic Reticulum protein 57)
    b. Calreticulin
    i. FUNCTION: blocks the antigen binding site of MHC class 1 molecules
    and stabilizes the structure of MHC class 1
  7. Once MHC class 1 is stabilized, it will leave the RER by TAPASIN (chaperon
    molecule)
  8. The peptides from the proteasome will be transported by TRANSPORTERS
    ASSOCIATED with ANTIGEN PRESENTATION/PROCESSING
  9. Once the MHC is close to the peptides, ERp57, Calreticulin, TAPASIN, will be
    degraded
  10. Once degraded, peptides will now bind to MHC class 1
  11. MHC class 1 together with peptides will now travel to the golgi apparatus and the GA
    have VESICLES which will be the pathway of MHC with peptide (MHC class 1
    molecules with peptide complex) to be presented to the cell surface
  12. MHC class 1 will interact to CD8+ molecules
  13. CD8+ has its own receptor (T cell receptor, CD8 receptor) which will check if the
    complex is MHC class 1
  14. Once confirmed it will trigger cytokines to kill the virus
59
Q

Mechanism Exogenous Pathway Class 2

A
  1. Ribosome in the RER will produce MHC class 2 molecule
  2. MHC class 2 molecule has a protein (Invariant chain; symbol Ii)
    a. Invariant chain: stabilizes and protects the binding site of Class 2 molecule
  3. Phagolysosome will be degraded to peptides
  4. The peptides will be transported in the vesicles
  5. Class 2 molecules will go out the RER with Invariant chain (complete structure) and go
    through the Golgi Complex to meet with peptides
  6. Once they meet, Invariant chain will be degraded and the degraded Invariant chain will
    form into CLIP FRAGMENT (Class II invariant chain peptide)
  7. Clip fragment: blocks the antigenic site of Class 2 MHC; Clip Fragment will exchange
    location with the peptides for the class 2 molecules and peptide to combine
  8. Once they combine, they will be presented to the cell surface where MHC peptide
    complex meets/binds to CD4+ cells of T helper
  9. CD4+ cell has its own receptors (T receptor and CD4 Receptor)
  10. These receptors will confirm if it is MHC class 2
  11. If confirmed, the CD4+ cells will release cytokines to TRIGGER B CELL to produce
    PLASMA CELLS to KILL ANTIGEN

1. IMMUNOSERO PRELIM (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions