B-Cell Development & Clinical Applications of ABs

Question 1

DNA mechanism that creates many billions of BCRs (B-cell receptors) and TCRs (T-cell receptors) using relatively few Ig and TCR genes

Answer 1

V(D)J Recombination

Question 2

V(D)J Recombination is mediated by two proteins:

Answer 2

RAG-1 and RAG-2

Question 3

RAG-1 and RAG-2 are expressed only in ______ and ______

Answer 3

RAG-1 and RAG-2 are expressed only in developing B-cells (Bone marrow) and developing T-cells (thymus)

Question 4

Recombination of light chains has a variable ____ region, a ____ regions and a constant ____ region

Answer 4

Recombination of light chains has a V region, a J regions and a CK region

Question 5

4 methods of generation Ab diversity

Answer 5

1. Germline
2. Combinatorial
3. Junctional
4. Somatic Hypermutation

Question 6

Germline diversity

Answer 6

multiple inherited V, D and j

Question 7

Combinatorial diversity

Answer 7

V+D+J and H+L

Question 8

Junctional

Answer 8

Imprecise joining and Tdt

Question 9

Somatic Hypermutation

Answer 9

Point mutations in Ab variable regions

Question 10

Affinity

Answer 10

strength of binding between an antibody’s Ag-binding site and its epitope.

Question 11

A complete deficiency of either RAG1 or RAG2 results the _______and a _______

Answer 11

A complete deficiency of either RAG1 or RAG2 results the absence of both B cells and T cells and a complete loss of adaptive immunit

Question 12

Abs on Mature (naive) B cell

Answer 12

IgD and IgM

Question 13

Switching from Naive B cell from IgM/IgD to one of the other antigens to form memory B cell or secreting plasma cell

Answer 13

Class switch recombination (CSR)

Question 14

Class switch recombination (CSR) and Somatic Hypermutation (SHM) occurs during ______ in ______ (location)

Answer 14

Class switch recombination (CSR) and Somatic Hypermutation (SHM) occurs during clonal expansion (after Ab stimulation) in Germinal centers of secondary lymphoid organs

Question 15

Stages of B-cell development

Answer 15

Stem cell->Pre-B cell->Imature B cell-> Mature B cell

Question 16

Stages of B-cell development

Answer 16

Stem cell->Pre-B cell->Immature B cell-> Mature B cell (naive B cell)

Question 17

What does mature B cell expresses that immature B cell doesn’t?

Answer 17

IgD

Question 18

What happens to self-reactive Immature B-cells

Answer 18

Get deleted by negative selection to prevent autoimmunity

Question 19

First antibody that appears in immune response

Answer 19

IgM

Question 20

____ and ____ are found in the surface of B-lineage cells and have clinical relvance

Answer 20

CD19 and CD20

Question 21

Type of immunity: Maternal IgG passed through placenta

Answer 21

Passive (natural)

Question 22

Type of immunity: Maternal IgA passed in milk

Answer 22

Passive (natural)

Question 23

Type of immunity: injection of pre-formed immune globulin

Answer 23

Passive (artificial)

Question 24

Type of immunity: infection with pathogen

Answer 24

Active (natural)

Question 25

Type of immunity: Immunization (vaccination

Answer 25

Active (Arficial)

Question 26

Immunity due to transfer of pre-formed antibody

Answer 26

Passive immunity

Question 27

Immunity due to response to antigen

Answer 27

Active immunity

Question 28

Intravenous immunoglobulin (IVIG)

Answer 28

Provides passive humoral immunity for the treatment of:

1. Primary humoral immunodeficiency diseases
2. Children with HIV

Question 29

Ig preparations with high titers for specific pathogens

Answer 29

Prepared using serum from donors who are immune to a particular pathogen.

Example: Rabies imune globulin (RIG)

Question 30

Convalescent plasma in the prevention or treatment of COVID-19

Answer 30

Transfer of Ab serum from an immune patient to a non immune patient

Question 31

IVIG, RIG, and Convalescent plasma are:

Answer 31

1. Examples of PASSIVE IMMUNITY

2. Consist of POLYCLONAL ANTIBODIES

Question 32

Polyclonal Abs

Answer 32

recognize multiple epitopes in antigen

Question 33

Monoclonal Ab

Answer 33

Recognize only one epitope in antigen

Question 34

By B-cells from mouse immunized with specific antibody, and and mouse myeloma cells (plasma cell tumor cells), you can get
______

Answer 34

By B-cells from mouse immunized with specific antibody, and and mouse myeloma cells (plasma cell tumor cells), you can get
“immortal” hybrid cells

Question 35

Enzyme-linked Immunosorbent Assay (ELISA)

Answer 35

If an antibody specific for an antigen is labeled with an enzyme, you can measure the presence and amount of that antigen by interacting the enzyme-labeled Ab with the antigen. The more antigen there is, the more Ab will bind. You add a substrate that gives color, and the more color the enzyme/antigen binds, the more of it is present

Question 36

Example of ELISA test and what it detects:

Answer 36

Home pregnancy test, and detects hCG

Question 37

Mouse monoclonal antibodies (mAbs) are not useful for therapeutic use because______

Answer 37

Mouse monoclonal antibodies (mAbs) are not useful for therapeutic use because humans will produce human anti-mouse antibodies (HAMA).

Question 38

Chimeric Ab

Answer 38

Antibody with human constant region and mice variable region

Question 39

Humanized Ab

Answer 39

Only uses CDRs (complimentary-determining regions) from mice and rest from humans

Question 40

Fully human antibody

Answer 40

Ab genetically engineered that had no mice parts

Question 41

Engineered Ab with lowest potential for immunogenicity

Answer 41

Fully Human Ab

Question 42

-ximab

Answer 42

chimeric Abs

Question 43

-zumad

Answer 43

humanized Abs

Question 44

-umab

Answer 44

fully human Abs