The present invention provides nanoparticles comprising: (a) an amphiphilic polymer with a number average molecular weight (Mn) of 20,000 g/mol or less; and (b) a peptide that is covalently linked to the polymer, wherein the peptide comprises 8 to 50 amino acids, including an N-terminal linker sequence comprising at least one Arg amino acid residue and a sequence comprising an MHC binding sequence comprising a T cell receptor epitope. The present invention further comprises compositions comprising respective nanoparticles and a liquid or lyophilized carrier as well as nanoparticles and compositions of the invention for use in inducing tolerance to a therapeutic compound (protein, viral vector, lipid vesicle), an allergen or to an autoantigen or for treating an allergy, an autoimmune disease, an exogenous antigen (transplantation antigens, drugs) or a food intolerance.