A 13-month-old girl with no fever (37.2°C), normal vital signs (HR 110/min, RR 28/min, BP 95/60 mmHg), and normal oxygen saturation receives a Haemophilus influenzae type b conjugate vaccine. She has no active infection and normal lymphocyte count (4,500/μL). Linking the capsular polysaccharide to a protein carrier most directly improves immunogenicity by inducing which of the following?
- A)Cytotoxic T cell killing of infected epithelial cells
- B)Complement activation through the alternative pathway
- C)Purely T independent B cell activation with no memory formation
- D)Immediate passive immunity through preformed antibodies
- E)T cell dependent class switching and memory B cell formationGABARITO
Explicação
Polysaccharide antigens alone are poorly immunogenic in young children because they stimulate mainly T independent B cell responses. Conjugating the polysaccharide to a protein carrier recruits helper T cell participation, allowing class switching, affinity ma... Ver explicação completa e trilha adaptativa →