Microfluidic processing of synovial fluid for cytological analysis.

Cytological analysis of synovial fluid is widely used in the clinic to assess joint health and disease. However, in general practice, only the total number of white blood cells (WBCs) are available for cytologic evaluation of the joint. Moreover, sufficient volume of synovial aspirates is critical to run conventional analyses, despite limited volume of aspiration that can normally be obtained from a joint. Therefore, there is a lack of consistent and standardized synovial fluid cytological tests in the clinic. To address these shortcomings, we developed a microfluidic platform (Synovial Chip), for the first time in the literature, to achieve repeatable, cost- and time-efficient, and standardized synovial fluid cytological analysis based on specific cell surface markers. Microfluidic channels functionalized with antibodies against specific cell surface antigens are connected in series to capture WBC subpopulations, including CD4+, CD8+, and CD66b+ cells, simultaneously from miniscule volumes (100 µL) of synovial fluid aspirates. Cell capture specificity was evaluated by fluorescent labeling of isolated cells in microchannels and was around 90% for all three WBC subpopulations. Furthermore, we investigated the effect of synovial fluid viscosity on capture efficiency in the microfluidic channels and utilized hyaluronidase enzyme treatment to reduce viscosity and to improve cell capture efficiency (>60%) from synovial fluid samples. Synovial Chip allows efficient and standardized point-of-care isolation and analysis of WBC subpopulations in miniscule volumes of patient synovial fluid samples in the clinic.

Opportunities and risks of diagnostic lab-on-a-chip systems in healthcare from a health system stakeholder's perspective.

AIM: The aim of personalized medicine is to respond to the needs of individuals with appropriate treatment. Lab-on-a-chip systems (LOCs) can help to individualize therapeutic algorithms at the point of care. Herein, we discuss the perspectives, demands and concerns associated with LOCs. METHODS: Interviews with 30 experts in the field of personalized medicine were conducted, addressing the requirements, potentials and risks of LOCs. The interviews were transcribed and evaluated by means of qualitative content analysis. RESULTS: The majority of experts emphasize a considerable potential for the lab-on-a-chip industry with the largest potential in the context of point-of-care diagnostics. The direct-to-costumer use is regarded as risky, in particular with respect to the reliability of the results. CONCLUSION: In addition to a major potential of the implementation of LOCs, their impact on delivery of healthcare have to be considered, and early communication between physicians and LOC developers and manufacturers have to be ensured.