The mucosal immune system must initiate and regulate protective immunity, while balancing this immunity with tolerance to harmless antigens and bacterial commensals. We have explored the hypothesis that mucosal dendritic cells (DC) control the balance between regulation and immunity, by studying the responses of human tonsil-derived DC to Neisseria meningitidis as a model organism. We show that...

Despite advances in medicine, infectious diseases remain major causes of death and disability worldwide. Acute or chronic infectious agents mediate host tissue damage and cause a spectrum of disease as diverse as overwhelming sepsis and shock within hours to persistent tissue inflammation causing organ failure or even cancer over years. Although pathogen exposure can cause disease via host-deri...

Mucosal immune responses to pathogenic gut bacteria and the mechanisms that govern disease progression and outcome have been researched intensely for decades. More recently, the influence of the resident non-pathogenic or 'commensal' microflora on mucosal immune function and gut health has emerged as an area of scientific and clinical importance. Major differences occur in the mucosal immune re...

The parasite fauna in cetaceans from Puerto Rico, the Virgin Islands, and the larger Caribbean region is poorly known. We provide the first records for parasite biodiversity among a diverse assemblage of cetaceans from the Caribbean Sea. Internal and external parasites and commensals were collected from stranded whales and dolphins salvaged in Puerto Rico, the United States and British Virgin I...

Respiratory infectious diseases are mainly caused by viruses or bacteria that often interact with one another. Although their presence is a prerequisite for subsequent infections, viruses and bacteria may be present in the nasopharynx without causing any respiratory symptoms. The upper respiratory tract hosts a vast range of commensals and potential pathogenic bacteria, which form a complex mic...

Biosynthesis of butyrate by commensal bacteria plays a crucial role in maintenance of human gut health while dysbiosis in gut microbiome has been linked to several enteric disorders. Contrastingly, butyrate shows cytotoxic effects in patients with oral diseases like periodontal infections and oral cancer. In addition to these host associations, few syntrophic bacteria couple butyrate degradatio...

Bacteria belonging to the genus Pantoea are common colonizers of plant leaf surfaces. Here, we present the draft genome sequence of Pantoea agglomerans 299R, a phyllosphere isolate that has become a model strain for studying the ecology of plant leaf-associated bacterial commensals.