抗原:BALB/c mice were immunized intraperitonally with COS cells transfected DQP (Domain 4 of the common beta-chain) expression constructs. The immunizations were repeated 4 times at 2-week intervals. Four weeks after the final immunization, a mouse was boosted with COS transfectants intravenously. Three days later, splenocytes were harvested and fused with NS-1 myeloma cells. Hybridoma supernatants were screened on CHO DQP cells by flow cytometry, with untransfected CHO cells as a control. All antibodies were from single hybridoma clones as selected by a limiting dilution method. MoAbs were purified from ascites fluid or hybridoma supernatant by a protein A sepharose column.