Last data update: Jun 11, 2024. (Total: 46992 publications since 2009)
Records 1-3 (of 3 Records) |
Query Trace: Sacchi CT [original query] |
---|
Triplex real-time PCR assay for the detection of Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae directly from clinical specimens without extraction of DNA
Ouattara M , Whaley MJ , Jenkins LT , Schwartz SB , Traore RO , Diarra S , Collard JM , Sacchi CT , Wang X . Diagn Microbiol Infect Dis 2018 93 (3) 188-190 This study presents a triplex real-time PCR assay that allows for the direct detection of Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae in one reaction without DNA extraction, with similar sensitivity and specificity to singleplex assays. This approach saves time, specimen volume and reagents while achieving a higher testing throughput. |
Triplex Real-Time PCR without DNA Extraction for the Monitoring of Meningococcal Disease.
Whaley MJ , Jenkins LT , Hu F , Chen A , Diarra S , Ouedraogo-Traore R , Sacchi CT , Wang X . Diagnostics (Basel) 2018 8 (3) ![]() Detection of Neisseria meningitidis has become less time- and resource-intensive with a monoplex direct real-time PCR (drt-PCR) to amplify genes from clinical specimens without DNA extraction. To further improve efficiency, we evaluated two triplex drt-PCR assays for the detection of meningococcal serogroups AWX and BCY. The sensitivity and specificity of the triplex assays were assessed using 228 cerebrospinal fluid (CSF) specimens from meningitis patients and compared to the monoplex for six serogroups. The lower limit of detection range for six serogroup-specific drt-PCR assays was 178(-)5264 CFU/mL by monoplex and 68(-)2221 CFU/mL by triplex. The triplex and monoplex showed 100% agreement for six serogroups and the triplex assays achieved similar sensitivity and specificity estimates as the monoplex drt-PCR assays. Our triplex method reduces the time and cost of processing CSF specimens by characterizing six serogroups with only two assays, which is particularly important for testing large numbers of specimens for N. meningitidis surveillance. |
Sequence diversity of the factor H binding protein vaccine candidate in epidemiologically relevant strains of serogroup B Neisseria meningitidis
Murphy E , Andrew L , Lee KL , Dilts DA , Nunez L , Fink PS , Ambrose K , Borrow R , Findlow J , Taha MK , Deghmane AE , Kriz P , Musilek M , Kalmusova J , Caugant DA , Alvestad T , Mayer LW , Sacchi CT , Wang X , Martin D , von Gottberg A , du Plessis M , Klugman KP , Anderson AS , Jansen KU , Zlotnick GW , Hoiseth SK . J Infect Dis 2009 200 (3) 379-89 ![]() BACKGROUND: Recombinant forms of Neisseria meningitidis human factor H binding protein (fHBP) are undergoing clinical trials in candidate vaccines against invasive meningococcal serogroup B disease. We report an extensive survey and phylogenetic analysis of the diversity of fhbp genes and predicted protein sequences in invasive clinical isolates obtained in the period 2000-2006. METHODS: Nucleotide sequences of fhbp genes were obtained from 1837 invasive N. meningitidis serogroup B (MnB) strains from the United States, Europe, New Zealand, and South Africa. Multilocus sequence typing (MLST) analysis was performed on a subset of the strains. RESULTS: Every strain contained the fhbp gene. All sequences fell into 1 of 2 subfamilies (A or B), with 60%-75% amino acid identity between subfamilies and at least 83% identity within each subfamily. One fHBP sequence may have arisen via inter-subfamily recombination. Subfamily B sequences were found in 70% of the isolates, and subfamily A sequences were found in 30%. Multiple fHBP variants were detected in each of the common MLST clonal complexes. All major MLST complexes include strains in both subfamily A and subfamily B. CONCLUSIONS: The diversity of strains observed underscores the importance of studying the distribution of the vaccine antigen itself rather than relying on common epidemiological surrogates such as MLST. |
- Page last reviewed:Feb 1, 2024
- Page last updated:Jun 11, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure