Genetics 9: Immunogenetics

Question 1

Complement System

Answer 1

Complement proteins perforate microbial cell membranes and attracts phagocytes/ immune cells

Question 2

Immune system recognizes _______ in gram negatives

Answer 2

Lipopolysaccharides

Question 3

Immune system recognizes _______ in gram positives

Answer 3

Peptidoglycan

Question 4

T cells come from

Answer 4

Thymus

Question 5

B cells come from

Answer 5

Bone marrow

Question 6

Helper T cells

Answer 6

Stimulate killer T cells and B cells

Question 7

Antigen presenting cells

Answer 7

Dendritic cells and macrophages

Engulf pathogens and then present them on their peptides on cell surfaces

Question 8

MHC class II

Answer 8

Molecule that transports foreign peptide to surface. Carries it on specialized groove.

Question 9

Co-stimulatory molecules

Answer 9

Presented on cell surface along with MHC class II to signal that foreign pathogens have been encountered

Question 10

Cytokines

Answer 10

Signaling proteins that mediate cell communication

Question 11

Immunoglobulin

Answer 11

Cell surface receptors of B cells that binds to peptides of pathogens

Question 12

Somatic hypermutation

Answer 12

B cells that have succesful immunoglobulin binding produce more with DNA mutations to get even better binding

Question 13

Plasma cells

Answer 13

B cells that bind to antigens for a long time rapidly divide and become plasma cells. Plasma cells secrete immunoglobulins to float around in blood stream.

Question 14

MHC Class 1

Answer 14

Found on almost all human cells, binds with small peptides and displays to killer T cells. If the small peptide is foreign, it is not recognized and then the cytotoxic cell signals it to kill itself

Question 15

Memory cells

Answer 15

Remain ready to fuck shit up should the antigen present itself again

Question 16

Immunoglobulin composed of

Answer 16

Two heavy and two light chains

Question 17

Immature b cells produce Ig__

Answer 17

IgM

Question 18

Class switching

Answer 18

As B cells mature they begin producing IgG, IgA, IgE and IgD

Question 19

Constant region of immunoglobulin is at ________ terminal

Answer 19

(C) Carboxyl-terminal

Question 20

Variable region located at ___________ terminal

Answer 20

(N) amino-terminal

Question 21

Constant region determines

Answer 21

Class of Ig moleculte (e.g IgA, IgM, IgE etc)

Question 22

Recombinase

Answer 22

Initiate double strand DNA breaks at specific DNA sequences flanking V and D segments. This leads to different combos of Ig molecules

Question 23

Somatic recombination

Answer 23

Recombination of DNA to produces different Ig molecules

Question 24

Affinity maturation

Answer 24

When Ig molecules cells recognize antigen, the cells producing them replaces cytosine with uracil to cause errors to DNA so new, slightly mutated antigens can be produced

Question 25

Natural Killer cell immunoglobulins mhc activity

Answer 25

Inhibit natural killer cells when binding to MHC class 1 but activate when MHC 1 is missing

Question 26

Cross reaction immune response

Answer 26

After infection, antigens from invaders (E.g. klebsiella) are similar to human antigens and are recognized by immune system which then causes self recognizing cells to proliferate and cause damage

Question 27

Adenosine deaminase (ADA) deficiency

Answer 27

Autosomal recessive disorder of purine metabolism resulting in metabolites toxic to immune cells. Causes SCID

Question 28

Chronic granulomatous disease

Answer 28

Phagocytes ingest bacteria and fungi but dont kill them. Results in granulomas

Question 29

Wiskott-Aldrich syndrome

Answer 29

X-linked recessive disorder that causes progressive T-cell dysfunction.

Question 30

SCID treatment

Answer 30

Bone marrow transplant, gene therapy

Question 31

X-linked agammaglobulinemia (XLA)

Answer 31

Lack B cells. Initially due to maternal antibodies have immune response but when supply dwindles, treament is needed. Treated with large amounts of Gamma globulin

Question 32

SCID biggest cause

Answer 32

x-linked recessive mutation that encodes gamma chain found in cytokine receptors. Without these, T cells cannot mature