The disclosure relates to a glycoconjugate vaccine conferring protection against Francisella tularensis infections and a method to manufacture a glycoconjugate antigen. A particular embodiment refers to a vaccine or immunogenic composition comprising: a carrier polypeptide comprising one or more T-cell dependent epitopes and one or more amino acid sequences having the amino acid motif D/E- X-N-X-S/T wherein X is any amino acid except proline and crosslinked to said carrier polypeptide is an antigenic polysaccharide wherein the polysaccharide is isolated from Francisella and is an O-antigen.
