[Development and application of polysaccharide conjugate vaccine carrier protein].

The development of polysaccharide conjugate vaccines, which convert polysaccharide antigens into T-cell-dependent immunogens through covalent conjugation with protein carriers, represents a critical strategy for enhancing immune protection in infants and young children. Globally licensed conjugate vaccines currently employ carrier proteins including Tetanus Toxoid (TT), Diphtheria Toxoid (DT), and Cross-Reacting Material 197 (CRM197). Recent advances have focused on three key areas: novel carrier protein discovery, optimized conjugation strategies, and evaluation of immune interference during co-administration of multivalent formulations. These efforts aim to achieve broader serotype coverage, prolonged protective efficacy, and simplified immunization schedules. This review synthesizes recent progress in carrier protein development, encompassing vaccine design principles, manufacturing processes, safety profiles, and epidemiological effectiveness. Furthermore, it critically examines current selection criteria for carrier proteins, their clinical applications, and persistent challenges, providing strategic insights to inform future conjugate vaccine development and immunization policy optimization in China.