CELL BANKING (MCB, WCB, CRYOPRESERVATION)

  1. WHAT IS CELL BANKING?
    The term “Cell Banking” refers to the process by which a specific type of cell is replicated, and stored for later use.
    DEFINITION: Cell Bank: a storage facility for frozen tissue samples held for research purposes and for surgical reconstruction of damaged body structur    es  
  2. HOW DOES CELL BANKING WORK?
    To establish a “bank” of cells, scientists take a selection of the type of cell they would like to store. They then grow that cell in what is called a cell culture. Once a stock of cells is created from the host cell, anyone has access to copies of that cell’s DNA. See figure 1 for an illustration of how this works.
  3. WHAT IS A CELL CULTURE?
    A cell culture is simply an artificial environment that is conducive to cell growth. Usually cells are placed in a container, bathed in a solution that contains all the necessary “food” that a cell needs. This allows it to grow within the confines of the container, at least until all of the food is consumed. Most cells studied in this way divide and reproduce by mitosis, which ensures all cells within a culture will be identical. This allows for the creation of a “cell stock” from which one can take copies of the host cell (See figure 1).
Figure 1
Mitosis: once cell becoming two cells.
  1. WHAT IS MITOSIS?
    Mitosis is the natural process by which a eukaryotic cell separates it’s DNA into two identical structures and divides into two separate individual cells with the same genetic structure (DNA).  
  2. WHAT IS XENOGRAFTING?
    Also referred to as “xenotransplantation”, xenografting is when tissue from one species is grafted, or inserted, into a different species. There are many practical implications of xenografting, whether it be for scientific research or potential treatments of various health problems, including but not limited to cancer, diabetes, liver failure, and Parkinson’s disease. The potential for xenografting to save lives is great, but it can be difficult for the tissue of one species to accept the tissue of another species. Sometimes the new tissue is seen as a foreign invader, and the body rejects it. Despite this, xenografting is an exciting new field of biology and progress is constantly being made. Altogen Labs offers over 50 validated cancer xenograft models.

DEFINITION
Xenografting: A surgical graft of tissue from one species to an unlike species (or genus or family). A graft from a baboon to a human is a xenograft. The prefix “xeno-” means foreign. It comes from the Greek word “xenos” meaning stranger, guest, or host. (Xeno- and xen- are variant forms of the same prefix.)

A cell culture.
  1. WHAT IS A STABLE CELL LINE?
    A stable cell line is sometimes synonymous with cell stock. It is a successfully grown and copied series of identical cells, which is specifically chosen for its cell type. There is a need to call certain cell lines “stable” because it can be a difficult process to successfully copy certain cells due to random mutations, transcription errors, and other factors. Often it requires completely sterile conditions to avoid contamination, and complex and/or expensive scientific equipment in order to ensure success, especially for certain cell types. Companies now provide a 28-day stable cell line development services, the common cell lines are readily available for generation of stably expressing custom cell line.
  1. WHAT IS TRANSFECTION?
    Transfection is a process of artificial introduction of genetic material into cells. A combination of the words transformation and infection, transfection was born. Unfortunately, there is no single reagent, kit, or transfection method that can be applied to all types of cells; transfection efficiencies vary dramatically depending on transfection method, reagent, protocol, and cell type being used. Altogen Biosystems developed cell line-specific transfection kits:

Each kit contains cell type specific Transfection Reagent, Transfection Enhancer Reagent, and recommended transfection protocol, making the whole process relatively simpler and more accessible.

  1. WHAT DOES IN-VIVO/IN-VITRO MEAN?
    In vivo (Latin for “within the living”) is experimentation using a whole, living organism as opposed to a partial or dead organism, or an in vitro (“within the glass”, i.e., in a test tube or petri dish) controlled environment. Animal testing and clinical trials are two forms of in vivo research. In vivo testing is often employed over in vitro because it is better suited for observing the overall effects of an experiment on a living subject. This is often described by the maxim in vivo veritas.   In vitro (Latin for “within glass”) refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments are commonly referred to as “test tube experiments”. In contrast, the term in vivo refers to work that is conducted with living organisms in their normal, intact state, while ex vivo refers to studies on functional organs that have been removed from the intact organism. Common examples of in vitro experiments include:
    a.Cells derived from multicellular organisms (cell culture or tissue culture)
    b.Subcellular components (e.g. mitochondria or ribosomes)
    c.Cellular or subcellular extracts (e.g. wheat germ or reticulocyte extracts)
    d.Purified molecules in the test tube (often proteins, DNA, or RNA, either individually or in combination)
    — Source: Wikipedia
  1. WHAT ARE RNAI SERVICES?
    RNAi services can be found at Altogen Labs
  1. WHAT IS THE DIFFERENCE BETWEEN A WORKING CELL BANK (WCB) AND A MASTER CELL BANK (MCB)?
    A Master Cell Bank represents cells “frozen in time”. At some point in recent history, a type of cell was seen as desirable for study, cloned, processed, and stored in extremely cold conditions, effectively freezing exact copies of that cell type. The storing process is usually done using small cryovials stored in liquid nitrogen (LN2) using a technique called cryopreservation. A working Cell Bank is the stock of cells that have been or are being thawed out, and grown in a cell culture (effectively cloned), taken from a sample of the MCB that is considered pure. Using a WCB one can create any number of copies of a specific cell line. Note that the sample of cells in the MCB does not get used up once this is done, only one copy of the cell in a MCB is needed to make more copies, so the MCB is preserved. WCB and MCB are not physical locations like Fort Knox where a large amount of cells are kept under guard, but rather terms used to describe the work of many scientists and organizations world-wide who have established their own independent cell banks. Different techniques are used to determine the relative purity of a cell culture, for example, there are ways to test its purity, identity, and genetic stability. Please note that not all Contract Research Organizations (CROs) follow the same guidelines, or perform the same types of tests.  
  2. WHERE CAN I FIND CELL BANKING SERVICES?
    Products and services related to cell banking, cryopreservation, cancer cell lines and primary cells, MCB, WCB, transfection products and services, CRO services, xenograft animal models, pharm/tox services, development of stable cell lines, and other topics discussed on this website can be found in our Links section.