Immunology and Infectious Diseases

Jos van der Vossen completed his PhD at Groningen University in 1988. During Postdoctoral Position he was involved in development of host-vector systems for optimizing bacterial strains for fermentation. Currently, he is about 30 years Scientist/Project Leader at TNO where, he is focussing on microbiome targeting interventions supporting human and animal heatlh.

TNO’s intestinal screening platform, the i-screen, is a versatile preclinical model allowing for determining modulatory effects of substances including prebiotics on the gut microbiota composition and activity. The presentation will elaborate on how this ex-vivo platform directs new opportunities for selection of beneficial susbstances like prebiotics that promote a healthy gut microbiota. The established protocols for collecting, handling and maintenance of fecal microbiota under anaerobic conditions ensuring viabilitiy and activity of bacteria are the elementary prerequisites for success of the i-screen. The gut microbiota from diverse population groups, e.g. adults, infants, obese, elderly as well as from diseased individuals support a tailored and if required a personalized approach. In addition, pathogenic species such as Clostridium difficile, C. perfringens, and other enteropathogens can be included in the microbiota to study ecological effects and potential interventions. The read out of the system is highly informative and a basis for decision making with regard to follow-up intervention studies. Effects on the composition of the microbiota, effects on pathogenic bacteria, metabolic activity as well as gene expression can be determined successfully. Such allows also for mode of action studies. By using the i-screen platform, effects of inulin, XOS, GOS, lactulose, HMO and hemp extracts on the gut microbiota were studied. Effects of prebiotics on extended spectrum beta-lactamase (ESBL) E. coli in the presence of antibiotics will also be discussed. Personal differences in microbiota composition and responses to antibiotics and prebiotics will also be highlighted.