The invention concerns polymeric media based on modified natural polysaccharides for removing one or both of Anti-A Antibodies and Anti-B Antibodies from human blood or plasma, the media comprising one or both of (i) a polymeric solid support with a blood group A Antigen ligand attached to the solid support at a ligand loading between 1-5 mg/mL of solid support, and wherein the media is stable under physiological pH conditions, and (ii) a polymeric solid support with a blood group B Antigen ligand attached to the solid support at a ligand loading between 1-5 mg/mL of solid support, and wherein the media is stable under physiological pH conditions.