ELISA試劑盒的用途

<p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">1<font face="宋體">．抗 原</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">在</font>ELISA<font face="宋體">中應用的抗原要求有較高的特異性、親和力和純度。主要有</font><font face="Calibri">3</font><font face="宋體">類，即自然抗原、人工合成抗原和基因重組抗原。自然抗原的純度不高，特異性不強。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">合成抗原一般為多肽片段，缺乏天然抗原所具有的立體結構表位，親和力不高，可能導致相應表位的抗體漏檢；基因重組抗原具有安全、特異性強、親和力高、產量大等特點，是一種比較理想的抗原，但其純化比較困難。</span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">2<font face="宋體">．抗 體</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">在</font>ELISA<font face="宋體">中應用的抗體可分為多克隆抗體（多抗）和單克隆抗體（單抗）。多抗取白免疫動物的抗血清，制備較簡單，但抗血清成分復雜，除含針對抗原（多個表位）的抗體外，還含有多種其他抗體，親和力和特異性相對要低于單抗，且制備周期長，批間差異較大。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">而單抗僅針對抗體的單一表位，親和力和特異性均較多抗高，且制備技術成熟，產量大，批間差異小，但結合位點的單一也正是其弱點之所在，在雙抗體夾心法中，如包被和指示抗體使用同一單抗，則由于結合位點的缺乏，容易造成假陰．性結果。在使用雙單抗一步法時，應注意抗原過剩時的</font>&ldquo;鉤狀效應<font face="Calibri">&quot;</font><font face="宋體">。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">3<font face="宋體">．固相載體</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">固相載體是</font>ELISA<font face="宋體">中用以分離結合標記物和游離標記物的主要手段，應與各種免疫活性物質有良好的結合性能并且不改變其免疫活性。常用的固相載體有聚苯乙烯塑料和硝酸纖維素膜。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">4<font face="宋體">．包 被</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><font face="宋體">將免疫活性物質（抗原或抗體）結合于固相載體上的過程稱為包被。常用的材料有聚苯乙烯、硝酸纖維薄膜等；常用的方法有吸附法、化學交聯法及親和素</font>-<font face="宋體">生物素間接包被法，特別是后一方法，效率高，而且可用以包被不易吸附在固相上的各種免疫活性物質。</font></span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p> <p class="MsoNormal"><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;">具體做法是先將鏈霉親和素包被在固相載體上，然后使與生物素化的抗原或抗體與之結合。由于親和素與生物素之間的高親和力，抗原或抗體即間接結合在親和素包被的固相上。</span><span style="mso-spacerun:'yes';font-family:宋體;mso-ascii-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:'Times New Roman';font-size:9.0000pt;mso-font-kerning:1.0000pt;"><o:p></o:p></span></p>