[Animal modeling] - Establishment of transgenic humanized ACE2 nude mouse model

  Objective To establish a human derived ACE2 (hACE2) transgenic nude mouse model with BALB/c-Nude nude mice as the background.

  Methods F1 generation was obtained by hybridizing hACE2 transgenic mice with male BALB/c Nude nude mice, F2 generation was obtained by backcrossing F1 generation hACE2 mice with BALB/e Nude nude mice, and F3 generation hACE2 transgenic nude mice were obtained by intercrossing F2 generation hACE2 mice. The growth and development, physiological indexes and immune indexes of hACE2 transgenic nude mice in F3 generation were compared with those of C57BL/6J wild-type mice, HACE2 mice and BALB/c Nude nude mice.

  Results (1) There was no significant difference in the growth and development indexes between hACE2 transgenic nude mice and C57BL/6J wild-type mice, hACE2 mice and BALB/e-Nule nude mice. (2) In the physiological indicators of hACE2 transgenic nude mice, the established hACE2 transgenic nude mice were similar to BALB/e-Nude nude mice. Pathological anatomy observation showed that there was no thymus in the mice. Compared with BALB/e Nude nude mice, the results of organ coefficient showed significant difference in spleen coefficient and liver coefficient (P<0.05). Compared with C57BL/6J wild-type mice and hACE2 mice, the percentage of neutrophils (NEU), percentage of lymphocytes (LYM) and percentage of monocytes (MONO) in blood routine examination showed significant differences (P<0.01). among="" the="" immune="" indexes="" of="" hace2="" transgenic="" nude="" there="" is="" no="" significant="" difference="" between="" c57bl="">d) white and greasy tongue coating+Stally+3N+StION14+8TICO+StalD+ECD+ECD+SKO+StaD+StalD-24-CEDVIIIIIIIIIIIANATE 0.01 and BALB/c-Nule nude mice.

  Conclusion The nude mice model of hACE2 transgenic immunodeficiency with BALB/e-Nude as background has been successfully established.