Han Lab

The human microbiome is a vast population of microbes that play an essential role in health and disease. Work in our laboratory is focused on the following aspects:

1. Investigating the role of oral bacteria in extra-oral infection and inflammation. Increasing evidence suggests that microbial communities specific to particular regions of the body are not isolated from each other but rather are mobile and interchangeable. For example, oral bacteria are not limited to the confines of the mouth and are frequently detected at extra-oral sites associated with infections and inflammation. We investigate the impact of the oral microbiome and oral health on pregnancy complications and gastrointestinal (GI) disorders.
2. Investigating the mechanisms of Fusobacterium nucleatum pathogenesis in pregnancy complications and colorectal cancer. F. nucleatum is a gram-negative anaerobic oral commensal prevalent in pregnancy complications including preterm birth, stillbirth, and neonatal sepsis. It has also been associated with GI disorders, including inflammatory bowel disease, colorectal cancer, and appendicitis. We have identified a unique adhesin, FadA, from F. nucleatum that plays an essential virulent role. FadA is thus a potential diagnostic and therapeutic target for disease detection and prevention. Our studies on FadA include continued analysis of its structure, function, regulation, as well as its clinical relevance in disease diagnoses, treatment, and prevention.
3. Developing genetic tools for mutant construction in bacteria. Studies of microbes are often hindered by the lack of genetic tools. My lab developed the technique to deliver DNA into bacteria by ultrasound, and we constructed the first double-crossover allelic exchange mutant in F. nucleatum. Developing bacterial genetic tools continues to be a focus in our lab.