Chip-based Blood Test Might Replace Bone Marrow Biopsies for Myeloma, Scientists Say
Researchers say they have developed a low-cost, reliable, chip-based blood test to detect multiple myeloma, which could replace the painful bone marrow biopsy.
Their study, “Isolation of Circulating Plasma Cells from Blood of Patients Diagnosed with Clonal Plasma Cell Disorders using Cell Selection Microfluidics,” was published in the journal Integrative Biology.
Multiple myeloma belongs to a group of conditions called plasma cell disorders (PCDs), which also includes monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM), which are considered precursor stages of multiple myeloma.
Smoldering multiple myeloma has a higher risk of progression to malignancy (myeloma) than MGUS.
Plasma cell disorders are characterized by an abnormal proliferation of plasma cells — a type of white blood cell that produces antibodies. As the malignant cells multiply uncontrollably, they produce large amounts of a specific antibody called the myeloma protein, or M-protein.
Circulating plasma cells (CPCs) in peripheral blood are considered an important prognostic marker in patients with plasma cell disorders. Their presence is a risk factor of progression to active disease in patients with MGUS and SMM, and increased levels of circulating plasma cells are associated with active disease and worse survival outcomes.
The diagnosis and treatment of multiple myeloma includes the testing of blood, urine, and bone marrow. The painful process of collecting a bone marrow biopsy is usually needed to confirm a myeloma diagnosis.
Now, a team of researchers at the University of Kansas developed an experimental, low-cost, reliable blood test that can deliver the same diagnostic information as a bone marrow biopsy. The device is currently being tested in clinical studies.
The test uses a device that exists on a plastic chip — about the size of a credit card — with specific antibodies attached to the surface of sinusoidal-shaped (curved like a sine wave) microchannels, which allows for the efficient capture of rare and specific cells.
To capture circulating plasma cells, researchers used antibodies against CD138, a protein known to be produced in both normal and malignant plasma cells, but at higher levels in malignant cells.
Blood samples from patients diagnosed with different plasma cell disorders and healthy people were analyzed for the presence of CPCs.
The device detected CPCs in 78% of patients with MGUS, in all patients with SMM and multiple myeloma, and none in healthy individuals. Also, patients with myeloma had significantly more CPCs than those diagnosed with MGUS and SMM.
The results suggest the new chip can improve diagnostic testing performance and accuracy compared to previous chips for multiple myeloma.
This new technology also comes with other advantages. It can process a blood sample directly without pre-processing, which minimizes sample loss and contamination, and it costs relatively little to produce because it’s made of plastic, “which makes it really appropriate for testing in a clinical setting,” Steven Soper, the study’s senior researcher, said in a press release.
The diagnostic chip for myeloma will undergo more testing and be brought to market by BioFluidica, which is planning a clinical testing lab at the KU Medical Center.
“Patients will soon be benefiting from this technology,” Soper said.
The team said additional studies are needed to examine the prognostic value of CPC detection in plasma cell disorders using the new device.
The technology has also been tested in other cancers, and some clinical tests are already underway.
“We’ll be able to see if patients are developing cancers before they have overt symptoms and help improve survival,” Soper added.
Soper hopes the day will come when this type of technology will be used as a routine and widespread blood test to screen for several types of cancer, long before the onset of symptoms.