Leena Mansperger
Research Mentor: Sharon Singh
Mentor Department: Pediatrics, Medicine
Author(s): Not Available
Session: Session 7 (4:00 PM – 4:50 PM)
Presentation Type: Poster 120
Abstract
Patients with sickle cell disease (SCD) are functionally asplenic, meaning their spleen was either removed or does not work properly, and have immune dysregulation early in life and therefore remain at high risk for invasive pneumococcal disease (IPD) caused by Streptococcus pneumoniae. The widespread use of pneumococcal conjugate vaccines such as PCV7, PCV13, and PCV15, and pneumococcal polysaccharide vaccines such as PPSV23, has significantly reduced IPD occurrence. However, individuals with sickle cell disease still experience infections due to a lack of antibody responses to these vaccines. The recently approved 20-valent pneumococcal conjugate vaccine (PCV20) expands coverage to include strains that are associated with IPD. PCV20, a newer protein-conjugated vaccine, may generate stronger, longer-lasting immune responses than the other vaccines, which are carbohydrate-based, making it a potentially more effective option for individuals with sickle cell disease. This observational study aims to evaluate both the strength and persistence of serotype-specific antibody responses after PCV20 immunization among patients with sickle cell disease at Michigan Medicine and Mott Children’s Hospital. Eligible participants include patients aged 1-99 years with HbSS, HbSC, or HbS-ß-thalassemia and a documented history of prior pneumococcal vaccination. Baseline pneumococcal IgG titers are obtained prior to vaccination, with follow-up lab testing performed 4-6 weeks, 12 months, and annually for up to 60 months post-vaccination. An adequate immunogenic response is defined as IgG concentrations = 1.3µg/mL for at least 12 of the PCV20-covered serotypes. By characterizing the durability of the immune response to PCV20 in patients with SCD, this study seeks to address critical gaps in knowledge about pneumococcal vaccination for this high-risk population. Findings may inform future vaccine scheduling and booster recommendations, while contributing evidence to support updates to vaccination guidelines for individuals with sickle cell disease.
