| abstract |
The present invention provides the application of nucleic acid molecules in the preparation of nucleic acid molecules and single domain antibodies. The nucleic acid molecule containing an immunoglobulin gene of a host animal or a fragment thereof, which comprises an IgH 5'-end enhancer of the host animal, an IgM switch region (Sμ) and an IgM sequence, all of which are of the host animal. IgM sequence, IgM lacks the CH1 sequence (IgM-dCH1), the IgG expression regulatory element is derived from the host animal, contains sequences such as Sγ, TM1, TM2 and PolyA, and contains the Cγ sequence of IgG (Hinge). , CH2 and CH3) are derived from the human sequence (Igγ-dCH1). The present invention ensures the normal development of B cells in transgenic animals, and it is the human single domain antibody that is expressed in the transgenic animal, which reduces artificial modification in the late stage and opens up the potential of the antibody as a drug. Can be enhanced. [Selection diagram] Fig. 1 |