Affinity support and method for trapping substance using the same

Abstract

Problems to be SolvedThe present invention provides an affinity support capable of trapping a substance by cooperative binding that is less likely to cause dissociation even when the substance is a molecule other than an antibody, and a trapping method using the same.Means to Solve the ProblemsA method of trapping a substance comprising the step of contacting an objective to be trapped with an affinity support comprising a support, a spacer bound to the support and an affinity substance bound to the spacer, so as to bind the objective to be trapped to the affinity substance, wherein each one of the objective to be trapped has a plural of affinity sites and the affinity substance binds to at least two of the affinity sites simultaneously.

1 - 9 . (canceled) 
     
     
         10 . A method of trapping amyloid β comprising contacting a sample containing amyloid β (1-28) or amyloid β (1-42) with an affinity support which comprises (a) a solid support, (b) a plurality of spacers directly covalently bound to the solid support, (c) and a plurality of immunoglobulins, immunoglobulin F(ab′) fragments, or F(ab) fragments comprising the F(ab′) or F(ab) region of a 6E10 antibody molecule, each bound directly covalently to a spacer, wherein the length of the spacer is 1 to 20 nm and wherein the interval between affinity substance-binding positions is 1 to 50 angstrom (Å), wherein the amyloid β has a plurality of affinity sites and at least two of the affinity sites of the amyloid β are bound by the immunoglobulins, immunoglobulin F(ab′) fragments, or F(ab) fragments simultaneously such that the amyloid β (1-28) or amyloid β (1-42) is trapped by the immunoglobulin F(ab′) or F(ab) fragments via cooperative binding. 
     
     
         11 . The method of trapping amyloid β of  claim 10 , wherein the amyloid β (1-28) or amyloid β (1-42) exists as a multimer or aggregate of a plurality of molecules, and the plurality of affinity sites exists on each multimer or aggregate. 
     
     
         12 . The method of trapping amyloid β (1-28) of  claim 10 , wherein the affinity support additionally comprises a plurality of immunoglobulins, immunoglobulin F(ab′) fragments, or F(ab) fragments comprising the F(ab′) or F(ab) region of a 4G8 antibody molecule, each bound directly covalently to a spacer such that two kinds of the immunoglobulin, immunoglobulin F(ab′) fragment, or F(ab) fragment are bound to the support in a mixed state. 
     
     
         13 . A method of analyzing the amyloid β (1-28) or amyloid β (1-42) trapped according to  claim 10  further comprising the steps of: (1) washing the surface of the affinity support to remove substances non-specifically adsorbed to the affinity support, (2) eluting the amyloid β bound to the immunoglobulin F(ab′) or F(ab) fragments from the affinity support; (3) collecting the amyloid β so eluted; and (4) analyzing the eluted amyloid β by surface plasmon resonance (SPR) or mass spectrometry. 
     
     
         14 . The method of trapping amyloid β (1-28) or amyloid β (1-42) of  claim 10 , wherein the interval between affinity substance-binding positions is 1.5 to 30 angstrom (Å).