Monoclonal Antibody Core Facility Department of Neuroscience Generation of Hybridoma Cell Lines Our hybridoma facility will generate hybridoma cell lines against a given antigen. The process is subdivided into four phases: Phase I: Immunization of Mice and Serum Screening (approx. 8 to 12 weeks) Immunization of five (5) mice (Balb/c) with antigen(s) provided by the investigator to stimulate antibody production. Typically, ELISA will be used to determine the highest titer mice and these will be used for cell fusion. Notes: 1. Approximately 2 mg of antigen is required for immunization. An immunogen can be provided as powder or in solution, though the immunogen must be soluble (no gel) for IV boosts at the end of the schedule. 2. The recommended concentration is ≥1 mg/ml (PBS). 3. An additional 4 mg of antigen in liquid for plate coating is required for screening by ELISA. 4. The screening strategy needs to be discussed with the core prior to the initiation of a monoclonal experiment. It is important that a screening strategy be defined beforehand which will result in the efficient detection of potentially useful hybridomas. Antibody-producing hybridomas need to be tested in the assay for which they will be used (i.e., if antibodies are to be used in Western blots, they need to be screened by Western blots) as soon as reasonably possible in the screening strategy. Phase II: Fusion and Screening of Hybridoma Supernatant (approx. 4-6 weeks) An antibody-producing mouse is selected for fusion of spleen cells with myeloma cells. Distribution of fusion product into several 96 well culture plates is performed. Screening of all wells containing fusion products will be assayed by ELISA, utilizing the antigen(s) provided by the investigator. The antibody secreting wells (up to 48 positives) with the higher titer (as determined by OD measurement) are grown in 24-well plates and retested by ELISA. Up to eight positive wells will be amplified and frozen for parental hybridomas. The investigator will be notified one or two days prior to supernatant harvest. Approximately 1 ml of supernatant will be given to the investigator for evaluation via their own specific assay. Results of the assay are required within 72 hours to insure that interesting hybriodmas are not lost to contamination or other unforeseen events. Notes: The Core can not guarantee that a mAb will be produced that will work in the investigator’s application. . 2 Standard Operating Procedure: Generate Hybridoma Cell Line Monoclonal Antibody Core Facility Department of Neuroscience Phase III: Cloning (approx. 4-6 weeks) Two of the best hybridomas will be selected and cloned by the limiting dilution method and screened by ELISA. Clones with the desired titer and specificity will be expanded, and the remaining antibody containing media (1 ml from up to 5 positive clones) from each of the subclones will be forwarded to the investigator for evaluation in the investigator’s specific assays. Positive clones with the highest titer (as determined by OD measurement) are temporarily frozen in duplicate vials. The investigator has two weeks to analyze and select the desired clones for recloning. Phase IV: Re-cloning (approx. 4-6 weeks) A clone (as chosen by the investigator from Phase III) will be re-cloned by limiting dilution technique and plated into five 96 well plates to generate a stable cell line. The growing cells are then screened for secretion of antigen specific antibody by ELISA. The media samples from up to 5 positive antibody-secreting clones (100-150 µl) will be given to the investigator for their evaluation. At this stage, the positive clones are transferred to a 24-well plate and kept in culture for 5 days, allowing the investigator to select a single clone for final expansion and subsequent cryopreservation. Otherwise, all 5 clones are expanded and temporarily frozen in duplicate vials. The investigator has 30 days to select final clone(s) for expansion and cell storage. Standard Operating Procedure: Generate Hybridoma Cell Line 3