A potency assay is the quantitative measure of biological activity, ideally it measures the ability of the product to elicit a specific response in a disease-relevant system (Figure 1; [1-4]).

How is cell potency tested?

Bioassays can provide a measure of potency by evaluating a product’s active ingredient(s) within a living biological system. Bioassays can include in vivo animal studies, in vitro organ, tissue or cell culture systems, or any combination of these.

What is AAV in pharma?

One of the most exciting advances in modern medicine has been the discovery of how the adeno-associated virus (AAV) can be used as an effective delivery system for therapeutic genetic material into living tissue. AAV gene therapy has broad therapeutic implications for a vast array of diseases.

Why is AAV nonpathogenic?

AAV, or adeno-associated virus, is currently the main viral vector that researchers use and further develop for gene therapy because it is considered to be non-pathogenic to humans and because it has been successfully altered to prevent its integration into the genome, thus eliminating DNA damage and unpredictable …

What is a potency test?

Potency testing involves comparison of a product’s biological activity to that of a reference preparation and cell-based potency assays are central tools used to measure drug efficacy during potency testing. They allow scientists to see how a particular dose of a drug will react in a given biological system.

What does potency mean in biology?

Definition. (general) The ability or capacity to perform something. (biology) The ability of a stem cell to differentiate into different cell types.

What is a totipotent stem cell?

Definition. Totipotent stem cells are cells that have the capacity to self-renew by dividing and to develop into the three primary germ cell layers of the early embryo and into extra-embryonic tissues such as the placenta.

How do you assey drug potency?

Potency assays often require antibodies as critical reagents in the measurement of drug binding or to measure functional effect of the drug. Antibody Solutions offers critical reagent development (e.g., antibodies, drug-target transfected cells, and ancillary reagents) for the creation of potency assays.

What is commitment in developmental biology?

During development, the commitment to make a particular tissue or organ is typically made long before overt differentiation. Embryonic commitment is presented as a central concept in developmental biology (Gilbert, 2010; Wolpert and Tickle, 2011) and yet its mechanism remains largely an enigma.

What is an AAV serotype?

AAV Serotypes These serotypes differ in their tropism, or the types of cells they infect, making AAV a very useful system for preferentially transducing specific cell types. The chart below gives a summary of the tropism of AAV serotypes, indicating the optimal serotype(s) for transduction of a given organ.

Is AAV a retrovirus?

Overall, AAV can be produced at a moderately high titer and can infect target cells efficiently, but less so than adenovirus. Retrovirus (e.g. MMLV) can introduce genetic material into the genome of the host cell, making it great for long-term stable expression.

What is an AAV capsid?

The capsid is the primary interface between the host and the vector genome. It is presumed to determine cell and tissue tropism. Indeed, the specificity and efficiency of transduction and the breadth of biodistribution of the AAV particle are dependent on the vector capsid.

What is the difference between adenovirus and AAV?

AAVs have a packaging capacity of ~4.5 kilobases, relatively low levels of protein expression, and the potential for long lasting gene expression. … Adenovirus vs. AAV.

Adenovirus AAV
Protein Expression High Low
Gene Expression Transient Potentially Long Lasting
Target Cell’s Immune Response High Very Low

Is AAV a DNA virus?

AAV as a virus The current consensus is that AAV does not cause any human diseases. It is composed of an icosahedral protein capsid of ~26 nm in diameter and a single-stranded DNA genome of ~4.7 kb that can either be the plus (sense) or minus (anti-sense) strand29.

How does AAV target cells?

When AAV infects a cell alone, its gene expression is repressed (AAV does not replicate), and its genome is incorporated into the host genome (into human chromosome 19).

How is potency measured?

Potency is the concentration (EC50) or dose (ED50) of a drug required to produce 50% of that drug’s maximal effect. Efficacy (Emax) is the maximum effect which can be expected from this drug (i.e. when this magnitude of effect is reached, increasing the dose will not produce a greater magnitude of effect)

What is a vaccine potency testing?

The use of potency control testing is a valuable tool for testing the actual relative strength of manufactured assembly lots of vaccine. Biological-based manufacturing methods are inherently variable and potency testing is a tool to ensure lot-to-lot consistency of commercial vaccines.

How do I know if I’m potent?

In ability to get an erection. Being able to get an erection sometimes, but not every time. Being able to get an erection but being unable to maintain it. Being able to get an erection but not have it be hard enough for penetration during sex.

What is the difference between potency and assay?

The key difference between assay and potency is that an assay is the testing of a material to determine its ingredients and quality whereas potency is the amount of a drug required to get an effect at its maximum intensity.

What determines the potency of stem cells?

Schöler The Potential of Stem Cells: An Inventory, is a cell’s ability to differentiate into other cell types. The more cell types a cell can differentiate into, the greater its potency.

What is mean by potent?

1 : having or wielding force, authority, or influence : powerful. 2 : achieving or bringing about a particular result : effective. 3a : chemically or medicinally effective a potent vaccine. b : rich in a characteristic constituent a potent drink.

What are the 4 types of stem cells?

Types of Stem Cells

What is blastomere and morula?

The two-cell blastomere state, present after the zygote first divides, is considered the earliest mitotic product of the fertilized oocyte. … When the zygote contains 16 to 32 blastomeres it is referred to as a morula. These are the preliminary stages in the embryo beginning to form.

What is the difference between pluripotent and totipotent stem cells?

These cells are called totipotent and have the ability to develop into a new organism. … This ability to become any type of cell in the body is called pluripotent. The difference between totipotent and pluripotent cells is only that totipotent cells can give rise to both the placenta and the embryo.

What is the difference between potency and purity?

Purity includes but is not limited to relative freedom from residual moisture or other volatile substances and pyrogenic substances. The word potency is interpreted to mean the specific ability or capacity of the product, as indicated by appropriate laboratory tests, to yield a given result.

How many types of assay are there?

Assays can be divided into three main categories based on the type of sample used – ligand-binding assays that measure binding between a ligand and a receptor, immunoassays that detect antibody-antigen binding, and bioassays that measure biological activity in response to certain stimuli.

What does Assay mean?

An assay is a process of analyzing a substance to determine its composition or quality. The term is often used in the mining industry to refer to tests of ore or minerals. The term assay is also used in the environmental, chemical and pharmaceutical industries.

What is the difference between Epiboly and involution?

a) Involution is the movement of cells toward an axis to extend that axis, epiboly is a flattening and spreading of epithelial cells to increase the amount of surface they cover, and convergent extension is the movement of cells inside the embryo as a coherent sheet.

How do cytoplasmic determinants work?

Cytoplasmic determinants are special molecules which play a very important role during oocyte maturation, in the female’s ovary. … Thus, all the organs of the future embryo are distributed and operating well thanks to the right position of the cytoplasmic determinants.

What exactly is this Drosophila Syncytium?

In early development, Drosophila melanogaster embryos form a syncytium, i.e., multiplying nuclei are not yet separated by cell membranes, but are interconnected by cytoskeletal polymer networks consisting of actin and microtubules.