兔抗大鼠神经甾体合成关键酶P450scc抗体的制备、特性鉴定及应用

目的: 制备兔抗大鼠神经甾体合成关键酶P450侧链裂解酶 (rP450sidechaincleavage, rP450scc)合成肽片段的抗体, 并检测rP450scc在大鼠脑组织及神经细胞中的表达。方法: 利用多肽固相合成法 (Fmoc法 )合成对称的 8分支 16肽rP450scc多重抗原肽片段 (rP450scc- 16), 并以其免疫雄性新西兰兔制备抗rP450scc -16抗体。采用ELISA、Westernblot和免疫细胞化学染色法鉴定抗rP450scc- 16抗体的特性。结果: 于末次免疫后 5d, 动脉放血分离血清, 用ELISA法检测抗rP450scc -16抗体的效价为 1∶6 400。Westernblot检测显示, 抗rP450scc- 16抗血清与大鼠的脑、睾丸及肾上腺组织蛋白于相对分子质量为 50 000处出现一条特异性的条带。用抗rP450scc -16抗体进行免疫细胞化学染色显示, 在正常大鼠的下丘脑、皮质、海马等区及培养的胶质细胞胞质中均可见棕色颗粒。结论: 制备出高特异性的兔抗rP450scc- 16抗体, 该抗体可检测rP450scc在正常大鼠脑组织中的表达和分布。

Preparation, identification and application of anti-P450scc antibody

AIM: To prepare rabbit anti-rat P450scc antibody, and to detect the expression of rP450scc in rat brain tissue and nerve cells. METHODS: An eight-branched polypeptide, rP450scc-16 was synthesized using solid phase synthesis (Fmoc) method. A Newzealand rabbit was immunized with rP450scc-16 and the serum was separated from the whole blood 5 days after the last immunization. The titer and specificity of the antiserum were evaluated, and the expression of rP450scc in normal rat brain and primary rat astrocytes was detected by using ELISA, Western blot and immunocytochemcal staining. RESULTS: The titer of the antiserum was 1:6,400. Western blot analysis showed that the rP450scc protein in rat brain, testis and adrenal gland homogenate was recognized by the antiserum as a single band at M(r) being 50,000, which indicated a high specificity of the antiserum. Hypothalamus, cerebral cortex, and hippocampus of rat brain and the cytoplasm of cultured rat astrocytes were positively stained by the antiserum. CONCLUSION: A highly specific anti-rP450scc antibody was prepared. The antibody can be used to study the expression and distribution of rP450scc in rat brain.