圖1展示了免疫共沉淀(Co-IP)的操作方法。可以根據(jù)抗體類型和靶蛋白進(jìn)行進(jìn)一步的優(yōu)化。Protein A/G免疫磁珠是進(jìn)行Co-IP實(shí)驗(yàn)的最佳方案。
表1 免疫共沉淀(IP)的操作方法
推薦的緩沖液配方
表2. 推薦的緩沖液配方
| 緩沖液 |
推薦配方(自備) |
| Binding buffer |
50 mM Tris, 150 mM NaCl, 0.1%-0.5% detergent (TritonX-100, Tween 20 or NP40), pH 7.5 |
| Wash buffer |
50 mM Tris, 150 mM NaCl, 0.1%-0.5% detergent, pH 7.5 |
| Elution buffer |
0.1 M -0.2 M Glycine, 0.1%-0.5% detergent, pH 2.5-3.1
(or 0.1 M citric acid, 0.1%-0.5% detergent, pH 2.5-3.1)
|
| Neutralize buffer |
1M Tris, pH8.0 |
實(shí)驗(yàn)之前的注意事項(xiàng)
1 進(jìn)行Co-IP實(shí)驗(yàn)之前,請仔細(xì)閱讀操作說明;
2 該產(chǎn)品需要使用磁力架
3 使用之前,請將Protein A/G免疫磁珠混勻;
4 Protein A/G免疫磁珠應(yīng)該保持在儲存液中避免干掉;
5 Protein A/G免疫磁珠應(yīng)避免凍融或離心;
6 為保證最佳結(jié)果,請選擇特異性好的抗體;
7 根據(jù)不同的抗體和抗原僅進(jìn)行實(shí)驗(yàn)方法的優(yōu)化;
表1. 抗體與Protein A/G及Protein A的結(jié)合能力比較
| Species |
Antibody class |
sProtein A/G |
sProtein A |
| Human |
Total IgG |
+++++ |
+++++ |
| IgG1, IgG2 |
+++++ |
+++++ |
| IgG3 |
+++++ |
+ |
| IgG4 |
+++++ |
+++++ |
| IgM |
+ |
+ |
| IgD |
- |
- |
| IgA |
+ |
+ |
| IgA1, IgA2 |
+ |
+ |
| IgE |
+++ |
+++ |
| Fab |
+ |
+ |
| ScFv |
+ |
+ |
| Mouse |
Total IgG |
+++++ |
+++++ |
| IgM |
- |
- |
| IgG1 |
+++ |
+ |
| IgG2a |
+++ |
+++ |
| IgG2b |
+++ |
+++ |
| IgG3 |
+++ |
+++++ |
| Rat |
Total IgG |
+++ |
+ |
| IgG 1 |
+++ |
+++ |
| IgG2a |
+++++ |
+++ |
| IgG2b |
+ |
+++ |
| IgG2c |
+++++ |
+++ |
| Cow |
Total IgG |
+++++ |
+ |
| IgG1 |
+++++ |
+ |
| IgG2 |
+++++ |
+++++ |
| Goat |
Total IgG |
+++++ |
+ |
| IgG1 |
+++++ |
+ |
| IgG2 |
+++++ |
+++++ |
| Sheep |
Total IgG |
+++++ |
+ |
| IgG1 |
+++++ |
+ |
| IgG2 |
+++++ |
+++++ |
| Horse |
Total IgG |
+++++ |
+ |
| IgG(ab), IgG(c) |
+ |
- |
| IgG(T) |
+++++ |
+ |
| Rabbit |
Total IgG |
+++++ |
+++++ |
| Guinea pig |
Total IgG |
+++++ |
+++++ |
| Hamster |
Total IgG |
+++ |
+++ |
| Pig |
Total IgG |
+++++ |
+++++ |
| Donkey |
Total IgG |
+++++ |
+++ |
| Cat |
Total IgG |
+++++ |
+++++ |
| Dog |
Total IgG |
+++++ |
+++++ |
| Monkey |
Total IgG |
+++++ |
+++++ |
| Chicken |
Total IgG |
- |
- |
Notes: "+"= weak binding, "+++"=medium binding, "+++++"=strong binding, "-"=no binding