Clinical Lab News of the Day: Cell Sorting Chip Technology May Pave the Way to POC Immune Profiling – Immunology
Cell sorting chip technology could pave the way for immune profiling of POCs
Author: LabMedica Editorial in Spanish
Updated February 22, 2024
Monitoring the immune system response of cancer patients during illness and treatment is important to achieve favorable outcomes. To do this, laboratories use flow cytometry to create an immune profile, which involves identifying and quantifying a patient’s immune cells at a specific time. This information is vital in determining the most effective treatment for a cancer patient. Continuing this profile throughout treatment helps doctors understand how well the treatment is working. Although immune profiling to guide therapy is an emerging area of cancer research and treatment, it has not been widely used in clinical practice due to the high cost, large size, and complexity of cytometric equipment. These machines are used only in specialized laboratories, and transporting blood samples to these institutions requires a lot of time and special conditions to preserve cell viability, making regular monitoring of cancer patients difficult. Now, new cell sorting chip technology could bring immune system monitoring into clinical practice and create a truly personalized cancer treatment plan.
Researchers at IMEC (Leuven, Belgium) have developed a cytometry and cell sorting technology that passes a sample of fluorescently labeled cells through microfluidic channels on a chip. The cells are directed to the excitation laser, detection unit and sorting junction, where the target cells are directed into the side channel using steam bubbles created by microheaters in a water-filled microchamber. Target cells can then be collected and quantified at the end of this fluid side channel. The technology could allow oncologists to use a portable, lunchbox-sized instrument in their office or daycare to periodically monitor a patient’s immune system.
Image: Cytometry setup using the IMEC cell sorting chip (photo courtesy of IMEC)
The process will involve drawing a drop of blood and inserting a chip cartridge into a benchtop testing tool, with results available within minutes. The chip, manufactured using standard technology on 200mm diameter silicon wafers, can be mass produced at an affordable cost, making it disposable if necessary to avoid cross-contamination of samples. Additionally, the manufacturing process allows for multiple microfluidic channels on a chip, providing high throughput without sacrificing sensitivity. This could mean a complete immune signature in just 10 minutes. By comparing these immune signatures to larger data sets, oncologists can quickly determine whether a therapeutic effect is being achieved.
In the first clinical trial of cell sorting chip technology, IMEC researchers together with colleagues at KU Leuven (Leuven, Belgium) set out to find out whether it could identify and quantify immune cells as efficiently as flow cytometry equipment. They decided to study CD8+PD-1+ T cells, a type of cell that has CD8 and PD-1 proteins on its surface. CD8 identifies cells as cytotoxic T cells, essential for recognizing and killing targets such as cancer cells. PD-1 is a protein that regulates T cell activity to maintain immune balance after attack by an invader. However, cancer cells can manipulate this pathway by overexpressing PD-1 ligands, suppressing the immune response and allowing uncontrolled growth. Analyzing PD-1-positive T cells in the blood of a cancer patient can indicate whether the cancer is using this immune evasion strategy.
In such cases, immune checkpoint inhibitor drugs can be used to prevent PD-1 proteins on T cells from binding to PD-1 ligands produced by tumors, restoring the T cells’ ability to attack cancer cells. The chip accurately identified PD-1-positive T cells in blood samples from 15 ovarian cancer patients, matching the accuracy of expensive conventional flow cytometry equipment such as FACS. This achievement marks an important step toward the development of an immune profiling tool, an innovative advance in cancer therapy that aims to personalize treatment plans for each patient.
“When you have cancer, you don’t want to waste precious time on expensive treatment that doesn’t help. This is actually true for ovarian cancer. “This type of cancer is mostly detected at a very late stage because the tumor has a lot of ‘free’ space to grow in the abdomen before the patient feels it as pain,” said Dr. An Koosmans, Ph.D. Professor at the University of Leuven and heads the Laboratory of Immunology and Tumor Immunotherapy. “Imec’s cell sorting technology has the potential to provide oncologists with a tool to perform initial and repeat immune profiling to select the most effective treatment.”
Related links:
IMEK
KU Leuven