Screening
The screening of the fusion is an important step. It must be performed quickly to avoid the loss of new hybridomas, specifically so that hybridomas that are taken forwards are in all probability what the client has ordered and lastly efficiently so that no potentially specific reagents are missed.
Screening will usually commence 7-10 days after the fusion date and on average lasts about 2 weeks.
Methods of screening
- ELISA
You can screen by ELISA against the immunising antigen.
- Staining of cell lines or tissues
If the distribution of the antigen in tissues or cell lines is known then using the supernatants to stain them can give an indication as to whether they are against the required protein. See more information under further characterisation.
- Staining of transfected cells
Using the supernatants to screen cells that have been transfected with the target protein of interest is a very accurate method for determining if the reagent made is specific.
See more information under further characterisation.
Cloning
The purpose of cloning a cell line is to make sure that each established culture comes from one parent cell. This ensures that the cell line is stable and will produce a steady quantity of antibody throughout its lifetime. If cell lines are not cloned efficiently the cell stock can be overwhelmed by a non-producing variant and antibody production can be lost.
Cloning can be performed as soon as the specificity of the cell line has been confirmed. It takes about one month from the start of cloning to the point where six vials of the cloned cell line are frozen down and stored in liquid nitrogen.
It is advisable to deposit important cell lines with another reputable cell storage facility to insure against catastrophic loss.