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The development of point-of-care, cost-effective, and easy-to-use assays for the accurate counting of CD4+ T cells remains an important focus for HIV-1 disease management. The CD4+ T cell count provides an indication regarding the overall success of HIV-1 treatments. The CD4+ T count information is equally important for both resource-constrained regions and areas with extensive resources. Hospitals and other allied facilities may be overwhelmed by epidemics or other disasters. An assay for a physician’s office or other home-based setting is becoming increasingly popular. We have developed a technology for the rapid quantification of CD4+ T cells. A double antibody selection process, utilizing anti-CD4 and anti-CD3 antibodies, is tested and provides a high specificity. The assay utilizes a microfluidic chip coated with the anti-CD3 antibody, having an improved antibody avidity. As a result of enhanced binding, a higher flow rate can be applied that enables an improved channel washing to reduce non-specific bindings. A wide-field optical imaging system is also developed that provides the rapid quantification of cells. The designed optical setup is portable and low-cost. An ImageJ-based program is developed for the automatic counting of CD4+ T cells. We have successfully isolated and counted CD4+ T cells with high specificity and efficiency greater than 90%.
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This content will become publicly available on January 1, 2026
Microfluidic Assays for CD4 T Lymphocyte Counting: A Review
CD4 T lymphocytes play a key role in initiating the adaptive immune response, releasing cytokines that mediate numerous signal transduction pathways across the immune system. Therefore, CD4 T cell counts are widely used as an indicator of overall immunological health. HIV, one of the leading causes of death in the developing world, specifically targets and gradually depletes CD4 cells, making CD4 counts a critical metric for monitoring disease progression. As a result, accurately counting CD4 cells represents a pressing challenge in global healthcare. Flow cytometry remains the gold standard for enumerating CD4 T cells; however, flow cytometers are expensive, difficult to transport, and require skilled medical staff to prepare samples, operate the equipment, and interpret results. This highlights the critical need for novel, rapid, cost-effective, and portable methods of CD4 enumeration that are suitable for deployment in resource-limited countries. This review will survey and analyze emerging research in CD4 counting, with a focus on microfluidic systems, which represent a promising area of investigation.
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- Award ID(s):
- 1846740
- PAR ID:
- 10591741
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Biosensors
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2079-6374
- Page Range / eLocation ID:
- 33
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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