CpG-OLIGODEOXYNUCLEOTIDE, IMMUNOGENIC COMPOSITION COMPRISING THE SAME, AND METHODS FOR PREPARING THE COMPOSITION AND STIMULATING IMMUNE RESPONSE THEREBY
CpG-oligodeoxynucleotides (CpG-ODN), as potent immune stimuli developed for using as adjuvant in different species, are disclosed herein. TLR9 is the cellular receptor for CpG-ODN, and current developed CpG-ODN has low activity to rabbit TLR9. Here, a type of CpG-ODN containing a GACGTT or AACGTT motif in about 11-14 deoxynucleotides was demonstrated to have potent immunostimulatory activity to rabbit TLR9, and capable of boosting a less toxic and potent antibody response in rabbits.
1 . A CpG-oligodeoxynucleotides (CpG-ODN) for eliciting a TLR9-activated immune response in a host, comprising GACGTT or AACGTT motif in 11-14 nucleotides.
2 . The CpG-ODN of claim 1 , wherein the CpG-ODN consists of 11-12 nucleotides.
3 . The CpG-ODN of claim 2 , wherein the CpG-ODN is selected from the group consisting of the nucleotide sequences of SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5 and SEQ ID NO: 6.
4 . The CpG-ODN of claim 1 , wherein the CpG-ODN is the nucleotide sequence of SEQ ID NO: 1.
5 . The CpG-ODN of claim 1 , wherein the host is mouse or rabbit.
6 . The CpG-ODN of claim 1 , wherein the GACGTT or AACGTT motif is not located at N-terminal or C-terminal of the CpG-ODN.
7 . An immunogenic composition for eliciting a TLR9-activated immune response in a host, comprising an antigen and the CpG-ODN of claim 1 .
8 . The immunogenic composition of claim 7 , wherein the host is mouse or rabbit.
9 . The immunogenic composition of claim 7 , wherein a ratio between the antigen and the CpG-ODN of claim 1 is in a range from 3:50 to 10:50.
10 . The immunogenic composition of claim 7 , further comprising an aluminum hydroxide gel.
11 . The immunogenic composition of claim 10 , wherein a concentration of the aluminum hydroxide gel is in a range of 0.2-1% (V/V).
12 . A method of preparing an immunogenic composition for stimulating a TLR9-activated immune response or enhancing a TLR9-activated immune response to an antigen, comprising mixing an effective amount of the CpG-ODN of claim 1 with an antigen and a suitable excipient.
13 . The method of claim 12 , wherein a ratio between the antigen and the CpG-ODN is in a range from 3:50 to 10:50.
14 . The method of claim 12 , further comprising mixing the CpG-ODN with an aluminum hydroxide gel.
15 . The method of claim 14 , wherein a concentration of the aluminum hydroxide gel is in a range of 0.2-1% (V/V).
16 . A method of stimulating a TLR9-activated immune response or enhancing a TLR9-activated immune response to an antigen, comprising administering to a host an effective amount of the immunogenic composition of claim 7 .
17 . The method of claim 16 , wherein the host is mouse or rabbit.
18 . The method of claim 16 , wherein the administering comprises subcutaneous injection.