Dr. Harkinsí research is in biofilm growth of pathogenic fungi. Biofilms are highly organized communities of microorganisms that are able to adhere to surfaces, proliferate and produce an extracellular matrix for protection. It is estimated that 70% of all infections of the human body are caused by a biofilm. The yeast Candida albicans is now the 3rd most common cause of blood stream infections in hospitalized patients. C. albicans can form efficient biofilms on medical devices that are inserted into the human body, which allow it to gain entry into the bloodstream. Once a biofilm is formed, it is very difficult to treat since the biofilm can be up to 1000 times more resistant to antimicrobial therapy.
The labís focus is in understanding the adherence of the organism to different types of plastics that are used in many of the medical devices, such as catheters. We have studied the role of certain enzymes that are involved in adherence and mature biofilm growth of clinical isolates of C. albicans and other species. A goal of the lab is to help determine and define signaling proteins needed by the isolates for biofilm formation, which may ultimately lead to new targets of antimicrobial therapy.
Dr. Harkins also has many collaborative projects with faculty in the Exercise Science Program, Physical Therapy and Chemistry departments including genotyping, measuring cytokines, chemistries, hormones and performing microbiological assays.
Analyzing cellular elements in saliva is currently one of the projects in Dr. Hou’s laboratory. While most scientists in saliva research look at cell-free supernatant, his focus is on cells in order to study the oral mucosal immunity. His hypothesis is that there are immune cells in the oral cavity and those cells could come from local lymphoid tissues and migrate from the circulation. Using saliva as a model, Dr. Hou would like to study the potential impact of stress on immune cells in saliva.
Although it is very convenient to collect saliva samples from subjects, there are multiple variables affecting the sample itself, e.g., time of the day, duration after the most recent meal/drinks, and method of collection. Dr. Hou has compared several collection protocols to establish optimized and standardized protocols for future projects. The presence of CD45 positive leukocytes in saliva from normal subjects, collected by various methods, provides a foundation for further investigation. Dr. Hou plans to continue phenotyping these leukocytes with other CD markers. In addition, subcellular microparticles from these leukocytes may also provide critical information in the oral cavity. Once the protocols are available in the lab, we will be able to test other hypotheses related to dynamics and functions of these immune cells in the oral mucosal environment. In the near future, we may contribute our knowledge to the development of saliva diagnostics. Other projects in my laboratory include the development of high content cellular analysis to look at these immune cells, an efficient separation / identification methodology for cellular elements in saliva, and software-assisted cluster identification to analyze flow cytometry data.
Clinical Laboratory Science (CLS) students have numerous opportunities to participate in research projects. Some choose to take CLLS 4995 (Independent Study course) which enables them to work with a CLS faculty member in his/her research laboratory. Others participate in the College of Health Sciences Summer Research program. Still others choose to do a research study for their senior project – they either do research in a CLS faculty member’s laboratory or at the student’s clinical site.