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A sample-preparation-free, automated, sample-to-answer system for cell counting in human body fluids


While many clinical laboratory tests are now highly automated, body fluid cell counting, particularly in low-cellularity samples such as cerebral spinal fluid (CSF), is often performed manually. Here, we report a simple, cost-effective method to obtain white and red blood cell counts from human body fluids such as CSF. The method consists of a compact, automated, and low-cost fluorescence microscope system, coupled to a sample chamber containing all of the necessary reagents in dry form to stain and prepare the sample. Sample focus and scanning are handled automatically, and the acquired multimodal images are automatically analyzed to extract cell counts. Comparison with manual counting on over 200 clinical samples shows excellent agreement. As the system counts a substantially larger image region than a standard manual cell count, we find our sensitivity to extremely low cellularity samples to potentially be higher than the manual gold standard, evidenced by our system recording images of cells in samples whose cell count was registered as “0” by a trained user. Thus, our system holds promise for routine, automated, and sensitive analysis of body fluids whose cellularity extends across a wide dynamic range.

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This research was funded by the Ministry of Science and Technology of China’s National Key Research and Development Program, Grant number 2016YFA0201300 (ZJS) and the Chongqing Municipal Science and Technology Commission, grant number cstc2017shmsA130083 (HD, ZJS), whose support is gratefully acknowledged.

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Correspondence to Hu Dou or Zachary J. Smith.

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Ethics approval

This study was approved by the Ethics Committee of the Children’s Hospital of Chongqing Medical University, approval number:(2016)年伦审(研)第(67)号 (Translation: 2016 IRB Research approval number 67).

Source of biological material

The samples utilized in this study were anonymized discarded patient samples from the Clinical Laboratory of the Children’s Hospital of Chongqing Medical University, which were not collected for the purposes of this study.

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The authors declare no competing interests.

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Lu, Q., Chu, K., Dou, H. et al. A sample-preparation-free, automated, sample-to-answer system for cell counting in human body fluids. Anal Bioanal Chem 413, 5025–5035 (2021).

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  • Clinical/biomedical analysis
  • Microscopic imaging
  • Point of care testing
  • Cell counting