Immunization with Bivalent Flagellin Protects Mice against Fatal Pseudomonas aeruginosa Pneumonia

Pseudomonas aeruginosa lung infections present a major challenge to healthcare systems worldwide because they are commonly associated with high morbidity and mortality. Here, we demonstrate the protective efficacy of type a and b flagellins (bivalent flagellin) against acute fatal pneumonia in mice. Mice immunized intranasally with a bivalent flagellin vaccine were challenged by different flagellated strains of P. aeruginosa in an acute pneumonia model. Besides the protective effect of the vaccine, we further measured the host innate and cellular immunity responses. The immunized mice in our study were protected against both strains. Remarkably, active immunization with type a or b flagellin significantly improved survival of mice against heterologous strain compared to flagellin a or b antisera. We also showed that after an intranasal challenge by P. aeruginosa strain, neutrophils are recruited to the airways of vaccinated mice, and that the bivalent flagellin vaccine was proved to be protective by the generated CD4+IL-17+ Th17 cells. In conclusion, bivalent flagellin vaccine can confer protection against different strains of P. aeruginosa in an acute pneumonia mouse model by eliciting effective cellular and humoral immune responses, including increased IL-17 production and improved opsonophagocytic killing

Rapid Detection of Rifampicin- and Isoniazid-Resistant Mycobacterium tuberculosis using TaqMan Allelic Discrimination

Objectives: Multidrug-resistant tuberculosis (MDR-TB) is a global problem that many countries are challenged with. Rapid and accurate detection of MDR-TB is critical for appropriate treatment and controlling of TB. The aim of the present study was to evaluate the TaqMan allelic discrimination without minor groove binder (MGB) as a rapid, efficient, and low-cost method for detection of drug resistant strains of Mycobacterium tuberculosis. Methods: A total of 112 M. tuberculosis isolates from cases with diagnosed TB were subjected to drug susceptibility testing (DST), using the proportion method. Resistant isolates were tested for characterization of mutations in the rpoB and KatG genes by TaqMan genotyping. Results: Of 112 M. tuberculosis isolates for which DST was performed, three, one, and two isolates were MDR, rifampin (RIF) resistant, and isoniazid (INH) resistant, respectively. According to the threshold cycle (Ct) and curve pattern of mutants, TaqMan probes detect all of the mutations in the analyzed genes (katG 315, AGC�ACC, rpoB 531, TCG�TTG, and rpoB 531, TCG�TGG). Conclusion: The present study suggests that drug-resistant strains of M. tuberculosis can be detected by pattern's curve or Ct with TaqMan probes without MGB in real-time polymerase chain reaction (PCR). © 2016

Erratum: Corrigendum to �katG Ser315 and rpoB 81-bp hotspot region substitutions: Reliability for detection of drug-resistant strains of Mycobacterium tuberculosis� (J. Global Antimicrob. Resist. (2016) 5 (92�93) (S2213716515001332) (10.1016/j.jgar.2015.12.001))

The authors regret that the following sentence in this article was incorrect, �In this study, 205 clinical isolates of M. tuberculosis were collected from TB patients hospitalised in Baqiyatallah Hospital, which is one of the TB centers in Tehran, during January 2012 to December 2013.� The text �January 2012 to December 2013� should have read �December 2013 to January 2015�. The authors would like to apologise for any inconvenience caused. �© 2016 International Society for Chemotherapy of Infection and Cance

High rates of nontuberculous mycobacteria isolation from patients with presumptive tuberculosis in Iran

Nontuberculous mycobacteria (NTM) can cause disease which can be indistinguishable from tuberculosis (TB), posing a diagnostic and therapeutic challenge, particularly in low- and middle-income settings. We aimed to investigate the mycobacterial agents associated with presumptive clinical pulmonary TB in Iran. A total of 410 mycobacterial isolates, obtained between March 2014 and January 2016, from 7600 clinical samples taken from consecutive cases of presumptive diagnosis of TB were identified. Phenotypic and molecular tests were used to identify the isolated organisms to the species level. Single-locus and multilocus sequence analysis based on 16S rRNA, rpoB, hsp65 and ITS locus were used to confirm the results. Of 410 consecutive strains isolated from suspected TB subjects, 62 isolates (15.1%) were identified as NTM. Patients with positive NTM cultures met American Thoracic Society diagnostic criteria for NTM disease. Mycobacterium simiae was the most frequently encountered (38.7%), followed by Mycobacterium fortuitum (19.3%), M. kansasii (17.7%) and M. avium complex (8.0%). Isolation of NTM, including M. simiae, from suspected TB cases is a serious public health problem and merits further attention by health authorities, physicians and microbiologists Keywords: Iran, mycobacterium, Mycobacterium simiae, nontuberculous, tuberculosi