Disclosed herein is an anti-CD22 heavy-chain variable domain (anti-CD22 VHH) antibody including an amino acid sequence as set forth in at least one of SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3, SEQ ID NO. 4, SEQ ID NO. 5, SEQ ID NO. 6, SEQ ID NO. 7, SEQ ID NO. 8, and combinations thereof.L'invention concerne un anticorps anti-CD22 à domaine variable de chaîne lourde (VHH anti-CD22) comprenant une séquence d'acides aminés telle que présentée dans au moins l'une des SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3, SEQ ID NO. 4, SEQ ID NO. 5, SEQ ID NO. 6, SEQ ID NO. 7, SEQ ID NO. 8, et des combinaisons de celles-ci.