Abstract: Disclosed herein are isolated peptides having nuclear localization activity and derived from the VP2 protein of chicken anemia virus (CAV). The isolated peptides are proven to be useful and effective in the nuclear delivery of a selected target substance, such as proteins, peptides, nucleic acids, pharmaceutically active agents, chemical substances, etc. The isolated peptide can transport a target substance, in particular a protein, into the nucleus of a mammalian cell by forming a conjugate with the target substance, or via an expression cassette capable of expressing a fusion protein having the isolated peptide and the target protein.

Abstract: Disclosed herein is an expression cassette adapted to be expressed in an E. coli host cell and having a first nucleic acid fragment encoding a full-length chicken anemia virus (CAV) VP1 protein. In particular, the first nucleic acid fragment has a 5?-region that encodes a N-terminal amino acid sequence of the full-length CAV VP1 protein and is codon-optimized as compared to a corresponding 5?-region of a wild-type CAV vp1 gene, thus to encode the full-length VP1 protein. Specifically, the optimized codons are introduced into the corresponding 5?-region of the wild-type CAV vp1 gene by codon replacements.

Abstract: A CpG DNA adjuvant in avian vaccines is disclosed, which includes an immunostimulatory oligodeoxynucleotide (ODN) having a sequence of SEQ ID NO: 2. The CpG DNA adjuvant in avian vaccines is advantageous to carry out large-scale production, specifically enhance avian innate and adaptive immune responses, and the CpG DNA adjuvant is hardly to be digested by DNase due to its particular structures.

Abstract: A CpG DNA adjuvant in avian vaccines is disclosed, which includes an immunostimulatory oligodeoxynucleotide (ODN) having a plurality of TCG tandem repeats at a 5?end, a poly-G structure at a 3? end, and at least one unmethylated CpG motif with avian specific flanking sequences at two ends thereof between the 5? end and the 3? end. The CpG DNA adjuvant in avian vaccines is advantageous to carry out large-scale production, specifically enhance avian innate and adaptive immune responses, and the CpG DNA adjuvant is hardly to be digested by DNase due to its particular structures.