Site specific ligation of proteins to synthetic particles

Abstract

The present invention relates to site-specific conjugation of synthetic particles to proteins.

We claim:  
     
         1 . A substantially homogenous conjugate composed of a synthetic particle attached to the N-terminous of a protein.  
     
     
         2 . The conjugate of  claim 1  wherein the synthetic particle is a monodisperse synthetic particle.  
     
     
         3 . The conjugate of  claim 1  wherein the synthetic particle is a monodisperse nanoscale particle.  
     
     
         4 . The conjugate of  claim 1  wherein the synthetic particle is a dendrimer.  
     
     
         5 . The conjugate of  claim 1  wherein the synthetic particle is a PAMAM dendrimer.  
     
     
         6 . The conjugate of  claim 1 ,  2 ,  3  or  4  wherein the protein is a four-helical bundle protein.  
     
     
         7 . The conjugate of  claim 1 ,  2 ,  3  or  4  wherein the protein is a cytokine.  
     
     
         8 . A pharmaceutical composition of the conjugate of  claim 1 ,  2 ,  3 ,  4 ,  5 ,  6  or  7 .  
     
     
         9 . A method for site specifically attaching a synthetic particle to the N-terminus of a protein, said method comprising the steps of: 
 a) attaching a spacer on the N-terminus of a protein;    b) forming a sulfhydryl on a synthetic particle at the amine; and    c) combining said sulfhydrylized synthetic particle to said spacer on the protein.    
     
     
         10 . A method for site specifically attaching a synthetic particle to the N-terminus of a protein, said method comprising the steps of: 
 a) converting a ser-terminated protein to an aldehyde;    b) converting the amine of a synthetic particle to a oxiamine; and    c) combining said aldehyde ser-terminated protein to said synthetic particle at said oxiamine.    
     
     
         11 . The method of  claim 9  or  10  wherein the synthetic particle is a monodisperse synthetic particle.  
     
     
         12 . The method of  claim 9  or  10  wherein the synthetic particle is a PAMAM dendrimer.  
     
     
         13 . The method of  claim 9  or  10  wherein the synthetic particle is a highly monodisperse nanoscale particle.  
     
     
         14 . The method of  claim 9  or  10  wherein the synthetic particle is a dendrimer.  
     
     
         15 . The method of  claim 9 ,  10 ,  11 ,  12 ,  13  or  14  wherein the protein is a four-helical bundle protein.  
     
     
         16 . The method of  claim 9 ,  10 ,  11 ,  12 ,  13  or  14  wherein the protein is a cytokine.