The number of study participants that maintained this twofold or greater increase above baseline levels 1 year following revaccination had diminished somewhat for all of the serotypes tested. for at least 5 years after vaccination. Revaccination induces a secondary surge in antibody concentration and opsonophagocytic activity Mogroside III-A1 that varies according to serotype but may be of lesser magnitude than the primary response. Revaccination of persons with SCI is not associated with significant adverse effects. Whether revaccination is needed beyond 5 years will require additional investigation. Keywords: Spinal cord injuries, complications; is the most common cause of community-acquired pneumonia and is the most common pathogen Rabbit polyclonal to ADRA1B leading to hospitalization for pneumonia (6). The risks of developing invasive pneumococcal bacteremic disease and dying from it increase with age (7). The 23-valent pneumococcal polysaccharide vaccine, licensed in the United States in 1983, has been shown to reduce the occurrence of pneumococcal pneumonia and bacteremia, especially in young adults (8). Our previous study (6) shown that an immune response was managed for at least 1 year following vaccination inside a cohort of individuals with SCI, and we recommended that administration of pneumococcal vaccine be part of standard care soon after injury. Studies of additional patient populations have shown that postvaccination antibody levels and protective effectiveness decline over time, suggesting that vaccine-induced safety may not be lifelong because the vaccine does not induce significant T-cell activation or immune memory (8C14). Since SCI happens most often in young individuals, the need for studies on long-term immunogenicity of the current 23-valent pneumococcal vaccine and the risks and benefits of revaccination is apparent. In the present investigation, we wanted to quantify and determine practical activities of antibodies directed against multiple representative pneumococcal serotypes, the effect of revaccination within the Mogroside III-A1 immune response, and the rate of recurrence of adverse reactions in a group of individuals with SCI who received 0.5 mL of the 23-valent pneumococcal vaccine PNEUMOVAX 23 (Merck and Co, West Point, PA) in the deltoid or lateral mid-thigh at least 5 years after primary vaccination. This study was performed with authorization of the Institutional Review Table for Human being Use, and educated consent was from all participants. METHODS Patient Populace and Specimen Collection The study population consisted of 23 community-residing adults with SCI who received main pneumococcal immunization from 1993 through 1998. Most participants were young to middle-aged males of either white or African American ethnicity who have been either tetraplegic or paraplegic, none of whom was more than age 65 years Mogroside III-A1 (Table 1). None of the participants experienced significant chronic underlying conditions or immunosuppressive ailments that would make them unlikely to mount an immune response following vaccination. Participants were revaccinated when 5 years (one month) experienced elapsed following a main vaccination. Sera were acquired just prior to, one month, and 1 year following revaccination. All sera were stored freezing at ?70C until tested. All serum samples from each individual were tested at the same time to assure comparability of results. Table 1 Characteristics of the Study Populace (N = 23) Open in a separate window Measurement of Anticapsular Antibody Concentrations Antibody concentrations against 5 pneumococcal serotypes (3, 4, 14, 19F, and 23F) included in the 23-valent vaccine and known to cause pneumococcal infections in adults were measured spectrophotometrically in microtiter plates coated with 100 L of serotype-specific pneumococcal polysaccharide antigens (American Type Tradition Collection, Manassas, VA) using an enzyme-linked immunosorbent assay (ELISA) (15). Data were imported into a desktop computer and stored as an ASCII text file. The Centers for Disease Control and Prevention (CDC) ELISA software program (15) abstracted the standard series, individual serum samples, and quality control samples from this file and calculated a standard curve using.