A low platelet count could mean life or death for patients fighting certain illnesses. Ongoing testing and research at Versiti’s Diagnostic Laboratories will help determine the impact that prescribed medications can have on platelet counts and patient outcomes.
Antibodies, or proteins produced by plasma cells in blood, are used by the immune system to neutralize perceived threats, like viruses. Sometimes, antibodies interpret medications as a threat, to the detriment of the patient taking the drug.
As part of their work, physicians at Yale University and Cornell University encountered two patients who were both taking oxaliplatin, a drug used to treat end-stage colon cancer. These physicians noticed that their two patients, when they were on oxaliplatin, experienced thrombocytopenia, or a dramatic drop in their platelet count, which can lead to severe bleeding and even death.
These physicians reached out to Brian Curtis, Ph.D., of Versiti’s Diagnostic Laboratories, whose platelet neutrophil immunology lab specializes in the kind of testing that helped these physicians understand what caused thrombocytopenia in some patients taking oxaliplatin. “We’re probably the only lab in the United States that does this testing and offers it for clinical purposes,” he said. “[We’re] maybe one of the few in the world.”
The results of this collaboration were recently published in an article in Letters to Blood: “Patients treated with oxaliplatin are at risk for thrombocytopenia caused by multiple drug-dependent antibodies.”
To help determine what caused this decrease in platelets, Dr. Curtis and his team tested serum samples with and without oxaliplatin. They found that, in the serum samples from the two patients in question, antibodies only bound to their platelets when oxaliplatin was present; this is called a drug-dependent antibody. What was most interesting, however, was that these two patients exhibited drug-dependent antibodies to a staggering four medications, all of which are used to treat cancer.
These four medications are among more than 80 that Dr. Curtis and a team at the Blood Research Institute found cause drug-dependent antibodies. Researchers are not sure why these drugs in particular cause a drop in platelets, but patients who develop drug-dependent antibodies to them can never take these medications again. They can, however, substitute with drugs of a similar class.
That’s where Versiti’s Diagnostic Laboratories’ expertise comes in. In addition to the platelet neutrophil immunology lab, our four other labs perform contracted research work for pharmaceutical companies that are developing new medications, including those that will treat conditions like thrombocytopenia in all patients, not just those taking oxaliplatin.
“It’s extremely unique for a blood center to have five clinical labs like that,” Dr. Curtis said. “I don’t know of a blood center that’s like that, at all, anywhere.”
Located in Milwaukee, Wisc., Vertisi’s Diagnostic Laboratories provide industry-leading, multidisciplinary diagnostic testing in the fields of transfusion medicine, hematology, transplantation and oncology, for physicians across the country.
About the expert: Brian Curtis, Ph.D., is Senior Director of Product Development & Clinical Labs at Versiti. Learn more about Dr. Curtis.