Cell walls affinity chromatography

Protein A is a cell-wall protein of Staphylococcus aureus with a molecular weight of 42,000. Since protein A binds specifically to the Fc part of IgG from various animals, it has been widely used in immunoassay and affinity chromatography. We found that protein A could be spread over the water surface to form a monolayer membrane by the LB method [21]. On the basis of this finding, an antibody array on the solid surface can be obtained by the following two steps. The first step is fabrication of an ordered protein A array on the solid surface by the LB method. The second step is self assembly of antibody molecules on the protein A array by biospecific affinity between protein A and the Fc of IgG as shown in Fig.34. 

Four rabbits were immunized each with 0.3 mL of the nonviable suspension of cells administered daily intravenously for 3 days, followed by a rest period of 4 days. This schedule was repeated for 5 weeks. After a 1-week rest period, a second administration of vaccine was used following the foregoing schedule. Blood samples were drawn weekly and serum was obtained. In 6 weeks the sera of the rabbits showed a high titer of antibodies directed at the cell-wall polysaccharide. The antisera from each rabbit were maintained separately. The antibodies were isolated from the serum by an affinity-chromatography procedure employing adsorbtion on lactosyl-... 

Heparin is able to inhibit smooth-muscle cells (SMCs) proliferation in vitro. SMCs are present in blood vessel walls and may proliferate in the case of an internal injury. The antiproliferative action of heparin is due to its internalization in SMCs, which is probably mediated by membrane receptors. Heparin-based affinity chromatography of SMCs membrane extracts allowed the separation of a few proteins, which could be implicated in the growth inhibition [15]. 

---