The silence of silk: tolerance of foreign proteins
 
                                        
                                    Immune reactions are a hazard of protein drug development. Why are some foreign proteins such as silk and botulinum toxin (Botox) tolerated when other proteins are not?
 
                         
                                        
                                     
                                        
                                     
                                        
                                     
                                        
                                     
                                        
                                     
                                        
                                     
                                        
                                     
                                        
                                    