Final Flashcards
What does metabolomics exclude?
enzymes, genetic material, structure molecules
What is the closest link to phenotype?
metabolomics
How does capiliary. electrophoresis work?
separate based on charge and partition coefficient
What can we do to speed up/ increase flow rate for Liquid chromatography?
sacrifice resolution
How do you calculate resolution?
R= (V2-V1)/(W1+W2/2)
What does it mean if R is >1.5?
good separation/resolution
What does particle size do to resolution?
smaller= better resolution
What can happen if high flow rate? Why?
loss of resolution due to back pressure
What is particle size for HPLC? WHat about flow rate?
5 microns
r8= 1ml/min
If column in LC is polar what happens?
polar things take longer to go through
What indicates the phase is non polar?
lots of carbons
What is difference between normal phase and reverse phase HPLC?
normal= stationary is polar
reverse= stationary is non polar
What is particle size for UPLC?
1.7-1.8 microns
For gas chromatography, what is the mobile phase?
gas- usually helium, H or N
For carrier gas what is pros and cons of each?
helium= best sensitivity, pricy
H= alright sense, flammable
N= bad sense but cheap
What is considered an abundant metabolite?
> 1 micro M
What is the database for metabolites?
HMDB
What is different between a targeted study vs a targeted?
target= know whats in sample
If someone is doing a metabolic fingerprint what can we assume?
dont know whats in it
What does metabolic profiling mean?
all involved in a disease state/ pathway
What is definition of pharmacometabolomics?
how metabolits change from a drug
WHat is path of biomarker discovery?
fingerprinting
then see if targets have
validation
clinical utility
approval
Why look at metabolomics?
fast, changes happen first before symptoms
What are the different matrixes for metabolomic study? pros and cons?
blood- easy but complex
Urine- not invasive, but different between age, gender
saliva= low amount
CSF- invasive
breathe- low concentration
tissue
Which matrixes are bad for proteomics?
urine and breathe
What makes antibodies?
B cells
Explain humoral immunity?
b cells bind to foreign and make antibodies
T cells bidn to antigen to kill
T helper bind to antigen and release cytokines to activate B and T cells
What is the structure of antibodies?
heterotetramer with 2 identical light and heavy chains
What portion of antibody binds to antigen and which binds to other cells?
Fab binds to antigen
Fc binds to cell
What do antibodies do?
neutralize, phagocytosis, lysis, NK
How are antibodies used in cancer?
stop angiogenesis= VEGFR and new interest in blocking checkpoints= nivolumab and iplimumab
Why can antibodies bind to many antigens?
diversity of CDR loops
How can we make a bunch of antibodies?
lots of immunoglobulin genes and recombination
What is the total diversity of antibodies in body?
> 1 billions
How can we produce (scientifically) antibodies?
humanized through hybridoma, through mice
bacteriophages
transgenic mice
human b cells
What has been a workhorse for protein engineering?
M13 bacteriophage
What is the success rate of MABs?
23% compared to 7% of small molecule drugs
How does bevacizumab work? How was it made?
stops VEGF= stop angiogenesis
made by humanized
How does mutations to Fc change function?
increase or decrease binding affinity
What are some bispecific antibodies mechanisms?
bridge two cells, double receptor inhibition/activation, piggybacck
What is a quadroma?
fuse two different hydroma to get bispecific
need advanced purification
What is knob-in holes tech?
mutate to get knob so that homodimerize doesnt happen so you get bispecific
What is cross mab tech?
knob to get proper bispecific but cross over happens on one of the heavy chain
What is the best success story of a bispecific antibody?
emicizumab for hemophilia
What is the most common site for bispecific antibodies?
PD1 and HER 2
How many approved bispecific antibodies?
3
Cons of antibodies?
high cost, poor penetration
Pros and cons of scaffolds?
Pros- low cost, better penetrate
cons- immunogenicity and poor stability
What is RNA interference? WHat is a key requirment?
gene silencing
requires dsRNA
What enzyme is needed to make silencing RNA from long dsRNA?
dicer
How do siRNA work?
promote degrade of mRNA
Where can dsRNA come from?
hairpin, complementary RNA
What is structure of siRNA?
21-23 nucleotide what a 2 nucleotide overhang on each 3 prime end
Where does siRNA act?
on RISC which cleaves the passenger strand and the guide strand stays on AGO part of RISC to bind to complementary mRNA to cleave
Which is another name for passenger and guide strands?
passenger= sense
guide= antisense
What is miRNA
micro RNA= ds stem loop
WHat is process of miRNA
miRNA gene transcribed= ds
cleaved by Drosha to get pre-miRNA
exportin 5 sends it to cytoplasm
dicer cuts off loop then it binds to RISC and loses passenger strand and same process
What is a key difference between miRNA and siRNA?
miRNA is not fully complimentary so it can bind to more sites
and miRNA passenger strand is discarded not cleaved
WHat is a key pro of RNAi therapuetics?
act on gene target more of all classes of proteins
and can go into cells
Cons of RNAi?
vulnerable to nucleases
poor stability
poor delivery because they cant permeate
What are a delivery system form for RNAi
viral vectors - Lentiviruses or AAV
Cons of viral vectors?
immunogenicity
expensive
mutagenesis
What are non viral delivery mechanisms?
polymer or lipid based
Which is more efficient Viral or non viral delivery?
viral
Where si the site of target for RNAi?
anywhere
What is CRISPR-cas9
genome editing
How many FDA approved CRISPAR?
1
How does CRISPR work?
cas 9 chops virus DNA/RNA, uses some of the pieces and inserts it to remember the virus
when it cuts we can add or delete
What causes sickle cell?
mutation in hemoglobin-beta gene in chromosome 11