Biotech Test 3 Set 2

Front 1

What is emphysema (3)

Back 1

1)alteration of lung architecture
2)destruction of bronchioles and wall of alveoli
3)results in abnormally enlarged airspaces

Front 2

Genetic mutation that causes familial emphysema

Back 2

342 Glutamic acid(E) to a lysine(k) in alpha1-antiprotease

Front 3

How to treat familial emphysema

Back 3

give alpha1-antiprotease from blood or recombinant

Front 4

OTHER NAMES FOR ALPHA1-ANTIPROTEASE (2)

Back 4

1)Alpha1-PI
2)ALPHA1-ANTITRYPSIN

Front 5

How is Alpha1-PI inactivated

Back 5

it has a Met in the AS that can be turned into MET sulfoxide to inactivate it

Front 6

Smoking effect on lungs (3)

Back 6

1)large number of macrophages to lungs after bronchial lavage
2)smoke causes the macrophages release a chemotactic to attract neutrophils to the lungs
3)smoke stimulates release of elastase from macrophages and neutrophils in the lungs

Front 7

Levels of alpha1-PI in familial emphysema pts

Back 7

less than 15% of normal

Front 8

Gene therapy for familial emphysema (4)

Back 8

1)part of liver removed
2)converted into single cells and cultured in vitro
3)retrovirus construct w/ corrected gene is introduced into cells under ex vivo conditions
4)modified cells are reintroduced

Front 9

Categories of gene involved w/ cancer (3)

Back 9

1)oncogenes
2)tumor suppressor genes
3)DNA repair genes

Front 10

When tumor suppressor genes are unregulated....(2) (and 3ex)

Back 10

1)cell divides when it should NOT
2)inhibitor signals fail to reach nucleus

ex)p53, BRCA1, APC

Front 11

When Oncogenes are unregulated... (and 4ex)

Back 11

1)cell divides in absence of stimulation by external growth factors

ex)ras, myc, jun, PDGF

Front 12

Gene therapy strategies (4)

Back 12

1)replacement and knockout gene therapy
2)suicide gene therapy
3)immunomodulatory gene therapy (modify cell to trigger immune response)
4)siRNA

Front 13

Gene transfer methods (broad categories) (2)

Back 13

1)viral
2)non-viral

Front 14

Replacement gene therapy for cancer (4)

Back 14

1)replacing mutated/missing (usually a tumor suppressor gene) gene w/ normal copy that keeps cell growth and division under control
2)can involve induction of apoptosis
3)production of changes in cell growth, behavior, invasiveness or metastatic ability
4)gene should exhibit GENETIC DOMINANCE (only need 1 normal copy of gene to restore fxn)

Front 15

Replacement gene therapy for cancer limitations (3)

Back 15

1)large # of target genes known to induce or maintain malignancy (cancer usually not due to just 1 mutation)
2)difficulty of transducing in enough cancer cells to result in a cure
3)BYSTANDER effect

Front 16

Bystander effect

Back 16

death of more cells than are actually transduced

Front 17

Knockout gene therapy for cancer approaches (3)

Back 17

1)deliver DOMINANT mutant oncogene to negate effect of cancer causing oncogene
2)inhibit translation of oncogene by inserting DNA that codes for RNA/ribozyme that will destroy the oncogene's RNA
3)reduce levels of oncogene product that are being made in cell via antisense mRNA or siRNA

Front 18

Suicide Gene therapy
a)involves...
b)aka...

Back 18

a)transduction of a gene that transforms a nontoxic form of a drug (prodrug) into a toxic substance
b)chemosensitization

Front 19

Suicide therapy ex (2)

Back 19

1)5-FC to 5-FU via cytosine deaminase (the transduced gene)
2)acyclovir to phosphorylated analog leading to cell death (via thymidine kinase, the transduced gene)

Front 20

Immunomodulatory gene therapy
a)works via...(2)
b)approaches used...

Back 20

a1)induction of cellular immune responses to metastatic lesions
a2)cytokine gene is introduced to tumor cell to stimulate a systemic immune response against tumor-specific antigens; vaccinating the pt

b)in vivo and in vitro

Front 21

Immunomodulatory ex vivo approach (3)

Back 21

1)modify tumor cells ex vivo w/ a cytokine gene
2)put modified cells back into pt after cell has been irradiated to prevent further cell division
3)letting immune system create a systemic antitumor response

Front 22

Transduction def

Back 22

intro of new genetic material into a cell using a viral vector

Front 23

Transfection def.

Back 23

intro of free genetic material typcially by chemical manipulation of cells

Front 24

Non-viral vectors

Back 24

use chemical or mechanical manipulation to intro genes into cells (used in vitro usually)

Front 25

4 Non-viral transfer methods

Back 25

1)in vitro microinjexn of DNA coated onto gold & using a GENE GUN to inject DNA into tissue
2)artificial membrans (liposomes) that fuse w/ cellular membranes and carry transgenes
3)complexes of DNA attached to small protein (ligands) that can bind to receptors on cancer cells and then bring DNA into the cell
4)creation of pores in cell memb. by electrical pulse to get foreign DNA into cell (electroporation)

Front 26

Retrovirus vector w/ co-transfection has...

Back 26

therapy gene and packaging sequence so virus only carries these 2 genes

Front 27

Retrovirus advantages (2)

Back 27

1)can intro a therapeutic gene where it will become stably integrated and expressed
2)can enter any cell making them very useful in vitro

Front 28

Retrovirus disadvantages (3)

Back 28

1)not very selective; limiting their use for direct admin into a person
2)can only infect/integrate into actively dividing cells
3)could put gene in a location promoting new oncogenesis

Front 29

Adenovirus desc. (5)

Back 29

1)DNA viruses
2)larger more complex than retrovirus
3)50 disctinct adenoviruses
4)include many common cold viruses
5)transgenes inserted where 2 viral genes that are critical for viral replication naturally exist

Front 30

Advenovirus vectors adv. (5)

Back 30

1)can put genes in dividing and NONdividing cells
2)can deliver siRNA and other antisense agents
3)high efficieny of infexn into human cell types b/c binds to surface receptor most common on human cells
4)infexns are generally stable over time
5)can package larger DNA molecules than retroviruses

Front 31

Advenovirus vectors limitations (3)

Back 31

1)can cause immune response in host
2)host can develop neutralizing Ig's
3)non-integrative vector that limits express of transgene to a few cell divisions

Front 32

Adenovirus as tumor specific killers (4)

Back 32

1)use the virus as a virus; killing a host cell
2)immunomodulatory strategies
3)transductional/transcriptional targeting
4)siRNA targeting

Front 33

Virotherapy w/ transDUCTional targeting (w/ adenovirus) mechanism (3)

Back 33

1)virus recognizes receptor made only by tumor cells
2)virus takes over cancer cells and makes copies til cell is dead
3)cell bursts and virus infects and kills other cancer cells

Front 34

Virotherapy w/ transCRIPional targeting (w/ adenovirus) mechanism (2)

Back 34

1)virus will infect normal and cancer cells
2)BUT will only replicate in tumor cells b/c it has a promoter that can only be turned on in tumor cells

Front 35

Adeno-associated virus vectors def.

Back 35

adeno-associated virus is a parovirus w/ a single stranded DNA genome of 5000bp

Front 36

Adeno-associated virus vectors adv. (3)

Back 36

1)small size makes them easy to manipulate genetically
2)integrate stably into a host genome
3)capable of infecting nondividing cells

Front 37

Adeno-associated virus vectors disadv

Back 37

1)small genome size limits amt of transgenic DNA that can be introduced into it

Front 38

Herpes simplex virus vector def.

Back 38

very infexous to epithelial cells; as well as nerve tissue ther natural target

Front 39

Herpes simplex virus vector adv (3)

Back 39

1)accomadate large amounts of transgenic DNA
2)high efficiency of entering a wide range of cells
3)remain dormant in cells w/o replicating, allowing for long-term expression of transgenes

Front 40

Herpes simplex virus vector disadv (3)

Back 40

1)toxic to cells in their replicative (more SEs)
2)induce immune reponse
3)potential problems for neuronal cells they enter

Front 41

Other viral vectors (3)

Back 41

1)epstein-barr virus
2)polio virus
3)engineered bacteriophages

Front 42

AA's consists of... (5)

Back 42

1)alpha carbon
2)COOH
3)NH2
4)R group
5)asymetic carbon center (EXCEPT GLYCINE)

Front 43

Ionization state of AA is...

Back 43

pH dependent

Front 44

Protein drugs differ from traditional drugs via...

Back 44

can retain 100% of chemical composition of active protein, yet be biologically inactive (via conformation differences)

Front 45

Never ____ protein solutions

Back 45

SHAKE

Front 46

peptide begins @ ___ and ends @ ____

Back 46

begins at free amino
ends at free COOH

Front 47

Protein degradation pathways (2)

Back 47

1)chemical
2)physical

Front 48

Chemical instability of proteins via... (3)

Back 48

1)covalent modification of protein via bond formation or clevage
2)results in generation of a new chemical entity
3)occurs thru some chemical rxn such as hydrolysis, deamidation, oxidation, racemization

Front 49

Hydrolysis def in relation to AAs

Back 49

cleavage of the "amide" or peptide bond

Front 50

____ has ASPARTATE-PROLINE hot-spots promoting hydrolysis

Back 50

human recombinant IL-11

Front 51

Deamidation happens to what peptides

Back 51

peptides containing AAs such as Gln or Asn undergo hydrolytic deamidation to produce a free carboxylic acid

Front 52

Deamidation of a peptide results in.... (2)

Back 52

1)conversion of a natural residue to an acidic residue
2)can alter biological activity and protein fxn

Front 53

Major pathway of protein degradation (in solution and lyophilized)

Back 53

OXIDATION

Front 54

Oxidation desc.

Back 54

occurs in presence of oxygen and is influenced by temp and metal ions (so store in plastic)

Front 55

____ residues are especially prone to oxidation

Back 55

cysteine

Front 56

How to protect proteins from oxidation

Back 56

Pack under nitrogen/argon/inert gas

Front 57

Racemization process (3)

Back 57

1)conversion of L-AAs to D,L-mixtures
2)occurs thru a carbanion intermediate
3)may create peptide bonds susceptible to proteolytic enzymes and alter biological activity

Front 58

Physical Instability
a)def
b)4 main classes

Back 58

a)no change in chemical composition yet results in an inactive or low activity product
b)denaturation, surface adsorption, aggregation, precipitation

Front 59

Denaturation
a)factors affecting it
b)can be...
c)denatured protein is generally...

Back 59

a)temp, pH, organic solvents/salts
b)reversible or irreversible
c)less soluble than native protein

Front 60

Surface adsorption (3)

Back 60

1)molecule prefers to localize @ the interface (solid-liquid/air-liquid)
2)leads to denatuation
3)larger proteins are more prone to it

Front 61

Flocculation?****

Back 61

proteins adhere to the wall of the containers, also referred to as frosting

Front 62

Desorption may lead to...

Back 62

aggregation and precipitation since hydrophobic inner core of protein is exposed @ aqueous phase

Front 63

Aggregation (3)

Back 63

1)occurs when hydrophobic regions of denatured protein interact w/ each other forming aggregates
2)minimized by maintaining protein in its native stable conformation
3)aggregated proteins generally lose biological fxn

Front 64

Precipitation (2)

Back 64

1)macroscopic equivalent of aggregation
2)usually occurs in conjxn w/ denaturation