Acquired, but not innate, immune responses to Streptococcus pneumoniae are compromised by neutralization of CD40L.
Infect Immun
; 68(2): 511-7, 2000 Feb.
Article
in En
| MEDLINE
| ID: mdl-10639411
ABSTRACT
Streptococcus pneumoniae is a significant pathogen of young children and the elderly. Systemic infection by pneumococci is a complex process involving several bacterial and host factors. We have investigated the role of CD40L in host defense against pneumococcal infection. Treatment of mice with MR-1 antibody (anti-CD154/CD40L) markedly reduced antibody responses to the pneumococcal protein PspA, elicited by immunization of purified protein or whole bacteria. In mice immunized with whole bacteria, MR-1 treatment reduced antibody responses to capsular polysaccharides but not cell wall polysaccharides. MR-1 did not suppress antibody responses to isolated capsular polysaccharides but did reduce the production of antibody to a capsular polysaccharide-protein conjugate, indicating that when presented in the context of whole bacteria, the humoral response to capsular polysaccharides is partially T-cell dependent. Despite the reduction of the protective humoral responses to pneumococcal infection, administration of MR-1 had no effect on sepsis, lung infection, or nasal carriage in nonimmune mice inoculated with virulent pneumococci. Thus, short-term neutralization of CD40L does not compromise innate host defenses against pneumococcal invasion.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Streptococcus pneumoniae
/
Membrane Glycoproteins
Limits:
Animals
Language:
En
Journal:
Infect Immun
Year:
2000
Document type:
Article
Affiliation country:
Estados Unidos