title: Prevalence and clonal distribution of pcpA, psrP and Pilus-1 among pediatric isolates of Streptococcus pneumoniae.
abstract: Streptococcus pneumoniae is the leading cause of vaccine-preventable deaths globally. The objective of this study was to determine the distribution and clonal type variability of three potential vaccine antigens: Pneumococcal serine-rich repeat protein (PsrP), Pilus-1, and Pneumococcal choline binding protein A (PcpA) among pneumococcal isolates from children with invasive pneumococcal disease and healthy nasopharyngeal carriers. We studied by Real-Time PCR a total of 458 invasive pneumococcal isolates and 89 nasopharyngeal pneumococcal isolates among children (total = 547 strains) collected in Barcelona, Spain, from January 2004 to July 2010. pcpA, psrP and pilus-1 were detected in 92.8%, 51.7% and 14.4% of invasive isolates and in 92.1%, 48.3% and 18% of carrier isolates, respectively. Within individual serotypes the prevalence of psrP and pilus-1 was highly dependent on the clonal type. pcpA was highly prevalent in all strains with the exception of those belonging to serotype 3 (33.3% in serotype 3 isolates vs. 95.1% in other serotypes; P<.001). psrP was significantly more frequent in those serotypes that are less apt to be detected in carriage than in disease; 58.7% vs. 39.1% P<.001. Antibiotic resistance was associated with the presence of pilus-1 and showed a negative correlation with psrP. These results indicate that PcpA, and subsequently Psrp and Pilus-1 together might be good candidates to be used in a next-generation of multivalent pneumococcal protein vaccine.
authors: Molecular Microbiology Department, University Hospital Sant Joan de Deu, Barcelona, Spain.
authors: Laura
authors: L
authors: Selva
authors: Pilar
authors: P
authors: Ciruela
authors: Krystle
authors: K
authors: Blanchette
authors: Eva
authors: E
authors: del Amo
authors: Roman
authors: R
authors: Pallares
authors: Carlos J
authors: CJ
authors: Orihuela
authors: Carmen
authors: C
authors: Muñoz-Almagro
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D002352:Carrier Proteins / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D009296:Nasal Cavity / Q000382:microbiology; D010612:Pharyngitis / Q000235:genetics / Q000382:microbiology / Q000517:prevention & control; D010614:Pharynx / Q000382:microbiology; D011008:Pneumococcal Infections / Q000235:genetics* / Q000378:metabolism / Q000517:prevention & control; D022242:Pneumococcal Vaccines / Q000235:genetics / Q000627:therapeutic use; D012220:Rhinitis / Q000235:genetics / Q000382:microbiology / Q000517:prevention & control; D013030:Spain; D013296:Streptococcus pneumoniae / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism / Q000472:pathogenicity*
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; C113653:PcpA protein, Streptococcus; D022242:Pneumococcal Vaccines