Comparison of monoclonal antibodies produced by in vitro and in vivo methods

S138 Abstracts

J ALLERGY CLIN IMMUNOL FEBRUARY 2004

SUNDAY 452

Comparison of Monoclonal Antibodies Produced by In Vitro and In Vivo Methods

M. Abebe, V. Kumar, S. Sevinc, H. M. Vijay; Environmental Health, Health Canada, Ottawa, ON, CANADA. RATIONALE: The need for the production of large amounts of specific monoclonal antibodies (Mabs) to detect and quantify indoor aeroallergens

depends on the induction of ascites mice. Stringent animal regulations have restricted investigators from relying on this method. Various innovative in vitro production methods have been developed with varying degrees of success. We have compared the production of Mabs by in vitro method, using Animal Component Free Medium in the CL-1000 flask with that of in vivo induced ascites in Balb/C mice. METHODS: Monoclonal antibodies were produced by immunizing Balb/C mice with cloned Alt a1 which is the major allergen of Alternaria alternata. Immunized spleen cells were fused with the Sp2/O mouse myeloma cell line using a hybridoma cloning kit. A clone with strong reactivity to cloned Alt a 1 was selected by ELISA and immunoblotting and compared with the ascites. Three batches of antibody harvests were made from the in vitro culture at intervals of 7 days while ascites were collected within 10 days. RESULTS: The average amount of antibody produced in vitro from the three harvests was 2.65mg/ml while the ascites gave 2.3mg/ml. The amount of antibodies from the three individual harvests was 3.11mg/ml; 3.78mg/ml and 1.37mg/ml collected on days 7, 14, and 21, respectively. The antibodies produced by both methods were able to recognize Alt a 1 in both ELISA and immunoblotting. CONCLUSIONS: The findings suggest that the Mabs produced by in vitro method can reduce and/or eliminate the need for ascites induction Funding: Health Canada

Abstracts S139

SUNDAY

J ALLERGY CLIN IMMUNOL VOLUME 113, NUMBER 2