Nomenclature and listing of celiac disease relevant gluten T-cell epitopes restricted by HLA-DQ molecules

Celiac disease is caused by an abnormal intestinal T-cell response to gluten proteins of wheat, barley and rye. Over the last few years, a number of gluten T-cell epitopes restricted by celiac disease associated HLA-DQ molecules have been characterized. In this work, we give an overview of these epitopes and suggest a comprehensive, new nomenclature

Evaluation of a novel real-time PCR test based on the ssrA gene for the identification of group B streptococci in vaginal swabs

<p>Abstract</p> <p>Background</p> <p>Despite the implementation of prevention guidelines, early-onset group B streptococci (GBS) disease remains a cause of neonatal morbidity and mortality worldwide. Strategies to identify women who are at risk of transmitting GBS to their infant and the administration of intrapartum antibiotics have greatly reduced the incidence of neonatal GBS disease. However, there is a requirement for a rapid diagnostic test for GBS that can be carried out in a labour ward setting especially for women whose GBS colonisation status is unknown at the time of delivery. We report the design and evaluation of a real-time PCR test (<it>RiboSEQ </it>GBS test) for the identification of GBS in vaginal swabs from pregnant women.</p> <p>Methods</p> <p>The qualitative real-time PCR <it>RiboSEQ </it>GBS test was designed based on the bacterial <it>ssrA </it>gene and incorporates a competitive internal standard control. The analytical sensitivity of the test was established using crude lysate extracted from serial dilutions of overnight GBS culture using the IDI Lysis kit. Specificity studies were performed using DNA prepared from a panel of GBS strains, related streptococci and other species found in the genital tract environment. The <it>RiboSEQ </it>GBS test was evaluated on 159 vaginal swabs from pregnant women and compared with the GeneOhm™ StrepB Assay and culture for the identification of GBS.</p> <p>Results</p> <p>The <it>RiboSEQ </it>GBS test is specific and has an analytical sensitivity of 1-10 cell equivalents. The <it>RiboSEQ </it>GBS test was 96.4% sensitive and 95.8% specific compared to "gold standard" culture for the identification of GBS in vaginal swabs from pregnant women. In this study, the <it>RiboSEQ </it>GBS test performed slightly better than the commercial BD GeneOhm™ StrepB Assay which gave a sensitivity of 94.6% and a specificity of 89.6% compared to culture.</p> <p>Conclusion</p> <p>The <it>RiboSEQ </it>GBS test is a valuable method for the rapid, sensitive and specific detection of GBS in pregnant women. This study also validates the <it>ssrA </it>gene as a suitable and versatile target for nucleic acid-based diagnostic tests for bacterial pathogens.</p

Group B Streptococcus vaccine development: present status and future considerations, with emphasis on perspectives for low and middle income countries.

Globally, group B Streptococcus (GBS) remains the leading cause of sepsis and meningitis in young infants, with its greatest burden in the first 90 days of life. Intrapartum antibiotic prophylaxis (IAP) for women at risk of transmitting GBS to their newborns has been effective in reducing, but not eliminating, the young infant GBS disease burden in many high income countries. However, identification of women at risk and administration of IAP is very difficult in many low and middle income country (LMIC) settings, and is not possible for home deliveries. Immunization of pregnant women with a GBS vaccine represents an alternate pathway to protecting newborns from GBS disease, through the transplacental antibody transfer to the fetus in utero. This approach to prevent GBS disease in young infants is currently under development, and is approaching late stage clinical evaluation. This manuscript includes a review of the natural history of the disease, global disease burden estimates, diagnosis and existing control options in different settings, the biological rationale for a vaccine including previous supportive studies, analysis of current candidates in development, possible correlates of protection and current status of immunogenicity assays. Future potential vaccine development pathways to licensure and use in LMICs, trial design and implementation options are discussed, with the objective to provide a basis for reflection, rather than recommendations