Objective To compare the preparation efficiency of mouse pox and mouse hepatitis antibodies between two substrains of BALB/c and Big-BALB/c (B-BALB/c) mice, and to provide a theoretical basis and reference for the selection of laboratory animals in the preparation of monoclonal antibodies induced in vivo through hybridoma. Methods Individuals weighing more than 5% of the weight of normal animals at 4 weeks of age (the criterion for late selection is more than 10%) were selected from a population of conventionally bred BALB/c mice and bred individually, and a subline of B-BALB/c mice was prepared after 10 generations of selection. A total of 40 BALB/c mice and 40 B-BALB/c mice aged 10 to 11 weeks, half male and half female, were selected and inoculated with the mousepox monoclonal antibody hybridoma cell line G23 or the murine hepatitis monoclonal antibody hybridoma cell line Y15 pre-treated with liquid paraffin, respectively. Mice ascites containing monoclonal antibodies were obtained by in vivo induction. The antibody titer was tested by indirect ELISA. The mice were grouped based on the sub-strains, gender and inoculation type of hybridoma to analyze the ascites production, antibody titer and antibody production, and to evaluate the antibody preparation efficiency of the two BALB/c mouse sub-strains. Results After 10 generations of breeding, the body weight of 10-week-old male and female B-BALB/c mice increased by 22.3% and 12.8%, respectively, compared with BALB/c mice of the same age. Compared with BALB/c mice, B-BALB/c mice had better tolerance and adaptation to secondary ascites collection. Compared with BALB/c mice, the ascites production and antibody titer during the preparation of antibodies in B-BALB/c mice were significantly increased, especially in the hybridoma cell line G23 vaccination group (both P＜0.000 1) . After inoculation with the hybridoma cell lines G23 or Y15, the average antibody production of B-BALB/c mice (14.99×104 U and 33.22×104 U) was higher than that of BALB/c mice (5.33×104 U and 19.31×104 U) (both P＜0.01). After inoculation with hybridoma cell line G23, the average antibody production per unit body weight of B-BALB/c mice (0.55×104 U/g) was higher than that of BALB/c mice (0.23×104 U/g) (P＜0.000 1). And the antibody production per unit body weight of female B-BALB/c or BALB/c mice was higher than that of male B-BALB/c or BALB/c mice (both P＜0.01). Conclusion B-BALB/c mice can be used as an alternative to BALB/c mice in the in vivo induction of monoclonal antibody preparation, which can achieve the purpose of reducing the number of experimental animals used, lowering the labor cost, and improving the efficiency of antibody preparation.
