We measured bactericidal antibodies against meningococci by a method which depends on the inhibition of [3H]thymidine uptake by bacteria in the presence of antibody and complement. A significant increase in antibody activity was found in sera from patients who had recovered from group A meningococcal meningitis (mean inhibition, 38.9 +/- 4.4%) compared with antibody activity present in sera fro...

Serogroup C meningococcal conjugate vaccines generally use diphtheria or tetanus toxoids as the protein carriers. The use of alternative carrier proteins may allow multivalent conjugate vaccines to be formulated into a single injection and circumvent potential problems of immune suppression in primed individuals. Bordetella pertussis fimbriae were assessed as carrier proteins for Neisseria meni...

Streptococcus pneumoniae is a major respiratory pathogen responsible for many diseases in young children and elderly. Because of the increasing antibiotic resistance of pneumococci recently, the need for development of an effective vaccine is more and more urgent. Since the 7-valent conjugate vaccine was licensed in the United States in 2000, its efficacy has been widely recognized. Effort on r...

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 β-thalassemia, but previous PPSV23s affect the memory B-cell response in a dose- and time-dependent manner. Clinical Trials Registration...

Meningococci have historically caused extensive illness among members of the United States military. Three successive meningococcal vaccine types were used from 1971 through 2010; overall disease incidence dropped by >90% during this period. During 2006-2010, disease incidence of 0.38 (cases per 100,000 person-years) among members of the US military was not significantly different from the inci...

During an etiology study of adults hospitalized for pneumonia, in which urine specimens were examined for serotype-specific pneumococcal antigen detection, we observed that some patients received 23-valent pneumococcal polysaccharide vaccine before urine collection. Some urine samples became positive for specific vaccine pneumococcal serotypes shortly after vaccination, suggesting false-positiv...

Background. The burden of pneumococcal disease in patients (pts) with end stage renal disease (ESRD) is high, with S. pneumoniae accounting for more than half of the reported cases of pneumonia in dialysis pts. A diminished immune response to pneumococcal polysaccharide vaccine can be observed in pts with chronic renal failure requiring dialysis. The response to 13-valent conjugate pneumococcal...

BACKGROUND The capsular polysaccharide of Salmonella enterica serovar Typhi, Vi antigen, is an essential virulence factor and a protective antigen. Similar to other polysaccharide vaccines, the protective action of Vi, both to the polysaccharide alone or when presented as a conjugate, is mediated by serum IgG Vi antibodies. The evaluation of Vi capsular polysaccharide based vaccines to prevent ...

Vi polysaccharide from Salmonella enterica serotype Typhi is used as one of the available vaccines to prevent typhoid fever. Measurement of Vi-specific serum antibodies after vaccination with Vi polysaccharide by enzyme-linked immunosorbent assay (ELISA) may be complicated due to poor binding of the Vi polysaccharide to ELISA plates resulting in poor reproducibility of measured antibody respons...

BACKGROUND Infections with some bacteria, including Streptococcus pneumoniae, have been associated with a reduced incidence of asthma. Components of S pneumoniae may have the potential to modulate allergic inflammatory responses and suppress the development of asthma. OBJECTIVES To determine if human S pneumoniae vaccines have the potential to suppress asthma by elucidating their effect on al...