Cambios en la epidemiología de neumococo en nuestro medio / Changes in pneumococcal epidemiology in our geographica area

conjugada heptavalente (PCV7), Streptococcus pneumoniae sigue siendo un importante problema de salud pública. Objetivo. Analizar la evolución de la enfermedad invasiva neumocócica en la era de la vacuna conjugada heptavalente con especial referencia a nuestra área geográfica. Método. Revisión no sistemática. Resultados. La introducción de la PCV7 se ha asociado con el fenómeno de reemplazo de serotipos en nasofaringe. El reemplazo implica que los serotipos no vacunales adquieren una ventaja ecológica para colonizar la nasofaringe. En consecuencia, aumenta su prevalencia como portadores y en una segunda etapa como productores de enfermedad. La neumonía con o sin empiema ha sido la presentación clínica principalmente relacionada con la enfermedad producida por serotipos no vacunales. El reemplazo de serotipos es un fenómeno multifactorial y otros factores distintos a la vacunación están también relacionados con este suceso. Conclusiones. Una nueva generación de vacunas conjugadas que incluyan un mayor rango de serotipos mejoraría la cobertura vacunal. Por otro lado, el desarrollo de vacunas proteicas que impidan la enfermedad invasiva pero que preserven la colonización, podría tener un impacto positivo de la vacunación antineumocócica a largo plazo(AU)

Introduction. Despite the use of pneumococcal conjugate vaccine (PCV7) Streptococcus pneumoniae remains a major public health problem. Objective. To highlight recent reports concerning invasive pneumococcal disease in the era of heptavalent conjugate vaccine in our geographical area. Method. Non-systematic review. Results. The introduction of PCV7 has been associated with the replacement phenomenon in nasopharynx. Replacement implies that non-vaccine serotypes acquire an ecological advantage for colonizing the nasopharynx and, consequently, increase their carriage prevalence and in a second step, the disease. Pneumonia with or without empyema has been the main clinical presentation related with the emergence of non-vaccine serotypes. Replacement is a multifactorial event and other factors unrelated to PCV7 are also responsible for this effect. Conclusions. A new generation of conjugate vaccines, which includes new serotypes and a wider spectrum of coverage, as well as the protein-based vaccines that may prevent invasion and preserve colonization, should help us achieve a positive long-term impact of pneumococcal vaccination(AU)

NMR structural studies of the ItchWW3 domain reveal that phosphorylation at T30 inhibits the interaction with PPxY-containing ligands.

In this work, we study the role of phosphorylation as a regulatory mechanism for the interaction between the E3 ubiquitin ligase ItchWW3 domain and two PPxY motifs of one of its targets, the Epstein-Barr virus latent membrane protein 2A. Whereas ligand phosphorylation only diminishes binding, domain phosphorylation at residue T30 abrogates it. We show that two ItchWW domains can be phosphorylated at this position, using CK2 and PKA kinases and/or with stimulated T lymphocyte lysates. To better understand the regulation process, we determined the NMR structures of the ItchWW3-PPxY complex and of the phosphoT30-ItchWW3 variant. The peptide binds the domain using both XP and tyrosine grooves. A hydrogen bond from T30 to the ligand is also detected. This hydrogen-bond formation is precluded in the variant, explaining the inhibition upon phosphorylation. Our results suggest that phosphorylation at position 30 in ItchWW domains can be a mechanism to inhibit target recognition in vivo.