The present invention is directed to a peptide for the delivery of anionic materials, such as anionic therapeutic agents, across a biological barrier, and methods of use thereof. The invention relates to a peptide comprising, or consisting of: X-(Xaa1)a-(Xaa2)b-Y-(Xaa3)c-(Xaa4)d-Z, in which each of X and Z is independently selected from Asn, Cys, Gln, Gly, Ser, Thr and Tyr； in which one of Xaa1 and Xaa2 is His and the other of Xaa1 and Xaa2 is Arg； in which one of Xaa3 and Xaa4 is His and the other of Xaa3 and Xaa4 is Arg； in which the amino functional group of X is, optionally, acylated； in which the carboxylate functional group of Z is, optionally, amidated； in which Y is selected from Ala and Trp； in which each of a and d is independently 2 to 4； and each of b and c is independently 2 to 4, or a salt or amide thereof. The invention also relates to a peptide for use in inducing an immune response in a subject in need thereof or a method for inducing an immune response in a subject comprising the administration of the peptide to a subject in need thereof. The invention also relates to a peptide for use in the treatment and/or prophylaxis of an infection, cancer, wounds in a subject in need thereof or a method for the treatment and/or prophylaxis of an infection, cancer, wounds comprising the administration of the peptide of the first aspect of the invention to a subject in need thereof.La présente invention concerne un peptide pour l'administration de matériaux anioniques, tels que des agents thérapeutiques anioniques, à travers une barrière biologique, et des procédés d'utilisation de celui-ci. L'invention concerne un peptide comprenant, ou consistant en : X-(Xaa1)a-(Xaa2)b-Y-(Xaa3)c-(Xaa4)d-Z, dans laquelle chacun de X et Z est indépendamment choisi parmi Asn, Cys, Gln, Gly, Ser, Thr et Tyr； l'un de Xaa1 et Xaa2 étant His et l'autre parmi Xaa1 et Xaa2 étant Arg； l'un de Xaa3 et Xaa4 étant His et l'autre parmi Xaa3 et Xaa4 étant Arg； le groupe fonctionnel amino de
