Neisseria meningitidis serogroup Y capsular polysaccharide-CRM197 conjugate (MenY-CRM197)

Neisseria meningitidis serogroup Y capsular polysaccharide-CRM197 conjugate is a vaccine antigen designed to elicit protective immunity against invasive meningococcal disease caused by serogroup Y. The target consists of the bacterial capsular polysaccharide, a critical virulence factor that allows the pathogen to evade the host immune system by inhibiting phagocytosis (CDC, 2022). Because pure polysaccharides are T-cell independent antigens that fail to induce long-term memory or effective responses in infants, they are covalently linked to CRM197, a non-toxic mutant of the diphtheria toxin (Pichichero, 2013). This conjugation transforms the polysaccharide into a T-cell dependent antigen, facilitating the recruitment of T-helper cells and the generation of high-affinity IgG antibodies and memory B-cells. Upon subsequent exposure to the bacteria, these vaccine-induced antibodies trigger complement-mediated lysis, effectively preventing life-threatening conditions such as meningitis and septicemia. This conjugate is a primary component of quadrivalent meningococcal vaccines like Menveo, which are used globally to reduce the burden of meningococcal disease (FDA, 2020).

Other names

Meningococcal group Y polysaccharide-CRM197 conjugateSerogroup Y capsular polysaccharide-CRM197 conjugateNeisseria meningitidis group Y oligosaccharide conjugateMenY-CRM

The conjugate induces the production of serogroup-specific bactericidal antibodies (primarily IgG) that recognize the capsular polysaccharide of Neisseria meningitidis serogroup Y, leading to complement-mediated lysis and opsonophagocytosis of the bacteria (FDA, 2020; Pichichero, 2013).