トラガカントガムベースのバイオインクによる3Dプリント：バイオプリンティング材料の新たなフロンティア

Extrusion-based bioprinting is widely used for fabricating cell-laden constructs; however, its success is highly dependent on the rheological and biological performance of the bioink. Natural polysaccharide gums have emerged as promising bioink components due to their biocompatibility and tunable properties. Among them, tragacanth gum (TG), a complex anionic heteropolysaccharide composed of tragacanthin and bassorin fractions, has gained increasing attention for extrusion bioprinting applications. TG exhibits pronounced shear-thinning behavior, high water uptake, and spontaneous gel-forming ability, which collectively enhance the printability, shape fidelity, and structural stability of bioinks. This review critically summarizes recent advances in TG-based hydrogels and bioinks, with emphasis on their molecular characteristics, rheological and physicochemical properties, and biological performance in extrusion bioprinting systems. The role of TG as a functional component in composite bioinks, particularly in improving mechanical integrity, extrusion consistency, and cytocompatibility, is discussed. Finally, current challenges and future research directions are highlighted to support the development and clinical translation of TG-based bioinks for tissue engineering applications.