Antigen-specific B-cell response to 13-valent pneumococcal conjugate vaccine in asplenic individuals with ß-thalassemia previously immunized with 23-valent pneumococcal polysaccharide vaccine.

Current guidelines recommend a combined schedule of a 13-valent pneumococcal conjugate vaccine (PCV13) and PPSV23 (23-valent polysaccharide vaccine) for asplenic individuals. We show that PCV13 induces a T-dependent immune response in asplenic individuals with ß-thalassemia, but previous PPSV23s affect the memory B-cell response in a dose- and time-dependent manner. Clinical Trials Registration. NCT01846923.