This is a critical stage in hybridoma production. An appropriate screening assay is vital for the efficient detection of hybridoma clones producing Mabs suitable for the end-users purpose. Screening strategies will be discussed prior to the start of the project.

The primary screening assay must handle 960 supernatants within a comparatively short time (1-2 days). Therefore we like to use 125I-antigen capture methods. These are run under antigen-limiting conditions and hence favor the selection of Mabs with high affinity. Under certain circumstances more involved primary screening methods may be required.

The secondary screening of 30-40 positive supernatants from the primary screen is then undertaken in end-use type formats (eg ELISA, western blot, immunocytochemistry or flow cytometry).

Approximately 2 mL of supernatant from the secondary screening will be given to the end user for evaluation in their own specific assay. Alternatively, and preferably, investigators may choose to perform both the primary and secondary screening in their own laboratory.