为提高肌肉抑制素(Myostatin，MSTN)免疫原性，进行了乙肝核心抗原(HBcAg)作为分子佐剂可能性的研究。利用PCR方法获得了MSTN的C端片段，并分别在乙肝核心抗原的N端、C端及中间位点融合，构建了3个融合表达克隆：pET-30a-MSTN/HBcAg(N)、pET-30a-MSTN/HBcAg(C)和pET-30a-MSTN/HBcAg(M)，转化大肠杆菌后IPTG诱导表达，然后利用Ni2+亲和层析纯化融合蛋白。应用重组蛋白免疫小鼠后利用间接ELISA法检测抗血清效价。结果表明：融合蛋白免疫效果要显著优于MSTN(P＜0.05)；融合蛋白MSTN/HBcAg(M)的免疫效果最佳。乙肝核心抗原可以作为分子佐剂以增强肌肉抑制素免疫原性。
马毅
,
陈小强
,
王文杰
,
李晴
,
关宏
,
安晓荣
,
陈永福
. 应用乙肝核心抗原增强肌肉抑制素免疫原性的研究[J]. 华北农学报, 2009
, 24(5)
: 197
-200
.
DOI: 10.7668/hbnxb.2009.05.041
Myostatin is a member of the TGF-βsuperfamily that functions as a negative regulator of skeletal muscle development in mammals.Targeting the myostatin pathway may be an effective strategy for increasing muscle growth.To improve immunogenicity of myostatin,the possibility of hepatitis B core antigen as molecular adjuvant was studied.First,myostatin C-domain was amplified by PCR and fused to the gene of hepatitis B core antigen at the position of N-terminal,C-terminal and internal respectively.Then three expression vector pET-30a-MSTN/HBcAg (N),pET-30a-MSTN/HBcAg(C) and pET-30a-MSTN/HBcAg(M)was constructed.The fused proteins were expressed in E.coli. and were purified by Ni2+ affinity chromatography.Then male Kunming white mice were immunized with single fused protein or recombinant C-domain.The indirect ELISA assay was used to detect the titer of antiserum against myostatin.The results shown:The immune effect of fused proteins was significantly better than that of recombinant C-domain(P<0.05);The immune effect of fused protein MSTN/HBcAg(M)was the best in three fused protein.These results proved that HBcAg could be used as molecular adjuvant to improve the immunogenicity of myostatin.
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