Study of the planar membrane on the silica compounds and its application

我们研究了巨噬细胞与含有半抗原磷脂的平面脂质单层的抗体依赖性结合。巨噬细胞与平面DMPC或DPPC单层的结合依赖于IgG亚类和半抗原浓度。在“固体”和“流体”脂质单层膜上的结合效率如下：IgGl IgG2a IgG2b IgG3。接下来，我们用纳秒荧光法确定了半抗原（TNP和丹酰）在脂质双层膜中的位置。研究发现，脂质半抗原的TNP（或丹酚）残基在膜表面的垂直位置相似，即使它们具有不同长度的间隔。这些实验解释了间隔长度如何调节抗体分子与膜中脂质半抗原的结合亲和力。最后，我们研究了一种新型的免疫场效应晶体管，它在ISFET栅极（SI_3N_4/SiO_2）表面通过含有脂质半抗原的单链脂质体（TNP-Cap-DPPE）融合而形成脂质膜。将小鼠单克隆抗tnp IgGl加入到溶液中，通过pH/pCO_2监测仪观察到一个时间依赖性电位（5-10mV）向负方向变化。作为对照实验，在溶液中加入非特异性的缪斯IgGl，未观察到电位变化。

We have studied the antibody-dependent binding of macrophages to supported planar lipid monolayers containing haptented phospholipids. The binding of macrophages to planar DMPC or DPPC monolayers was dependent on IgG subclasses and hapten concentrations. The binding efficiencies were as follows on both 'solid' and 'fluid' lipid monolayer membranes; IgGl IgG2a IgG2b IgG3. Next, we determined the location of haptens (TNP and dansyl) in lipid bilayer membranes by nanosecond fluorometry. It was found that TNP (or dansyl) residues of lipid haptens locate at the similar vertical position on the membrane surfaces even if they have different length spacers. From these kinds of experiments it was explained how the spacer length can modulate the binding affinity of antibody molecules to the lipid hapten in the membrane. Lastly, we have studied a new type of immuno-FET which has lipid membranes on the surface of an ISFET gate (SI_3N_4/SiO_2) by the fusion of single unilamella liposomes containing lipid haptens (TNP-Cap-DPPE). When mouse monoclonal anti-TNP IgGl was added to the solution, a time-dependent potential change (5-10mV) towards negative was odsedved by a pH/pCO_2 monitor. As for a control experiment, non-specific muse IgGl was added to the solution, no potential change was observed.