2018-2019

Breaking the Diagnostic Barrier for Hemoglobin Diseases in Low and Middle Income Countries

7% of the world’s population live with an inherited hemoglobin disease. One of the most austere and well- known hemoglobin diseases is sickle cell anemia that is caused by the recessively transmitted sickle hemoglobin gene. Hemoglobin diseases have the highest prevalence in sub-Saharan Africa, in Central India, and in Southeast Asia, mainly in low and middle income countries. In these regions, these diseases go mostly undiagnosed, which leads to early mortality. For example, up to 90% of the babies born with sickle cell anemia in sub-Saharan Africa die before age five due to lack of timely diagnosis. The World Health Organization estimates that at least 70% of these deaths are preventable with simple, cost-effective interventions, such as early point-of-care screening followed by widely available and affordable treatment and care. To break the diagnostic barrier and to improve treatment of these diseases worldwide, we develop new diagnostics. Our research primarily focuses on the fundamentals of red blood cell mechanics, biofluid mechanics, microfluidics, and electrophoresis. We apply our basic understanding in these areas to improve patients’ access to timely diagnosis and effective treatment. In this talk, I will provide an overview of our translational research activities and field-tests of new diagnostics in the US, and worldwide, including, Nigeria, India, and Thailand.

Microfluidics and Functional Genomics Related to Microbial Communities

Molecular tools related to specific functions of microbial communities are helpful in deciphering the presence and activity of harmful or beneficial microorganisms. Medium to high throughput microfluidic systems play a key role in the design and application of such tools. In this talk, I will highlight key attributes of selected microfluidic systems using examples related to microbial systems. Such examples will include harmful (e.g., antibiotic resistant bacteria, waterborne pathogens) as well as beneficial bacteria (e.g., organohalide respiring bacteria). Implications of various issues including sample matrix, target multiplexing, field deployability, reaction chamber volume, and need to recover amplified nucleic acids products for further analysis will be discussed.

Micro-playgrounds for motile bacteria

Flagellar motility is widespread in bacterial species living in diverse environments and plays an important role during complex processes such as plant root colonization, host infection, or collective migration. Even though the fundamental mechanisms of motility and chemotaxis are well characterized, especially in Escherichia coli, the specific adaptations of different bacterial species to their respective ecological niches has been difficult to investigate in controlled laboratory conditions. Natural environments are dynamic and often have a complex physical structure. I will discuss how microfluidics and single-cell tracking allowed for the identification of a fundamental tradeoff in the chemotactic performance of E. coli when faced with chemical gradients of different length-scales. Then, I will discuss our current efforts to characterize the behavior of human gut pathogens in intestinal mucus.