Cell biology and society Flashcards
Katalin Kariko
First suggested synthetic mRNAs as a means to address diseases. UPenn thought it wasn’t a good idea and demoted her, but she was able to resolve the main issues with mRNA to allow COVID vaccines to be developed using this technology.
Initially, what were the 2 main issues with mRNA technology?
- mRNA causes an immune reaction and could be degraded. The solution was to change a few bases (modified mRNA)
- How do you get mRNA into cells so that it could synthesize the protein of interest and secrete it? This is where Pfizer and Moderna took notice- vaccines use a lipid envelope
How do mRNA vaccines work?
The mRNA is used to synthesize a spike protein. This closely mimics a native viral infection and leads to B and T cell responses. mRNA can be mass produced, and these vaccines are made much more quickly than traditional vaccines- saves time in a pandemic situation.
Lab on a chip
Is typically a small disposable system that requires sophisticated microfluidic channels
built into the device, and is often the size of a dime. Can be used for drug toxicity testing, to study BBB function, to detect disease states such as HIV and possibly circulating tumor cells, and may be used in the the future at “point of care” in a doctor’s office to test for disease states
Disadvantages of fetal bovine serum (4)
- FBS introduces unknown factors to the media that may complicate experiments
- FBS may harbor animal viruses and, as such, is not appropriate to use in stem cell
expansion for cells destined for cell therapy. - FBS is expensive
- FBS contains animal proteins that may stick to human cells such as stem cells making
these cells unsuitable for cell therapy.
Which tissue engineered constructs have been developed? (4)
- Skin (epidermis)
- Bladders
- Neovaginal tissue/organs
- Extracorporeal liver assist devices
Genomic and cDNA cloning is commonly used by molecular biologists. What is the chief advantage of cDNA cloning compared to genomic cloning?
Complementary DNA (cDNA) cloning starts with mRNA, not the entire genome. As such, the end product (the
library) is smaller.
3 parent genetic engineering protocol
Nuclear transfer by placing the nucleus of the diseased mother into an egg of a non-
diseased mother once the latter’s nucleus has been removed. Allows mothers with mitochondrial diseases to have children without the disease.
NHEK (Normal Human Epidermal Keratinocytes)
Used to develop EpiDerm MatTek Corporation’s engineered skin. The cell source presented some technical/legal issues
when this construct was first developed 20 years ago. Foreskin was used as source cells.
Veridex
Used to identify circulating tumor cells
Liquid biopsy
It is designed to detect a biomarker that reflects a disease state- can be associated with analyzing circulating tumor cells, cell free DNA or other
molecules. It requires a small sample of blood, urine or cerebrospinal fluid. It is considered a core requirement for the future of personalized medicine
Value based pricing
How to value expensive new drugs like Erbitux based on their clinical effectiveness
Restriction nucleases/enzymes
An enzyme that cleaves DNA into fragments at or near specific recognition sites within molecules known as restriction sites. They are found in bacteria and can generate blunt or sticky ends. They are often used in conjunction with genomic cloning.
What is the function of siRNA/shRNA?
Small interfering RNA/short hairpin RNA. siRNA/shRNA can block the expression of select genes.
Craig Venter is known for
He was the first to sequence the human genome. He also created the first self replicating synthetic bacterial cell.
Bioheart and biolife
Focus on cell therapy
Detergents
Used when one is performing decellularization of whole organs to produce biological
scaffolds for subsequent seeding of cells. They manipulate hydrophobic-hydrophilic interactions among molecules in biological samples. In protein research, detergents are used to lyse cells (release soluble proteins), solubilize membrane proteins and lipids, control protein crystallization, prevent non-specific binding in affinity purification and immunoassay procedures, and are used as additives in electrophoresis.
Yeast
Critical for identifying cell division genes. They can exist as diploids or haploids and can generate temperature sensitive mutants. They do not require serum or selective medium to grow.
“Living Dots” is a new type of approach to grow cells in an unusual format. What type of
cell is being used in conjunction with this new media modality?
Stem cells
How is RT-PCR different from PCR?
Measures the abundance of mRNA transcripts with an emphasis on those that are in low abundance
shRNA
A hairpin like nucleotide sequence that can be permanently integrated into the nuclear
genome and once expressed can suppress select gene expression by binding to select
mRNA
Transfection
A procedure that introduces foreign nucleic acids into cells to produce genetically modified cells. Liposomes, electroporation, optoperforation, viruses, calcium phosphate and
micropipettes are all used for transfection
Biologic
A drug such as a monoclonal antibody that is typically produced by cells and once
harvested can be used to treat diseases.
Golgi complex is responsible for
Modifying and sorting newly synthesized proteins
The CFTR gene codes for
Chloride channel protein. It is defective in people with cystic fibrosis.
GVA
An anti-mitotic drug. it inhibits the growth of tumor cells by halting cells in mitosis and is not toxic to normal cells. It can be used to treat cancer, and may be able to be extracted from parsley or dill
