The organisms that cause visceral leishmaniasis, a potentially deadly version of the parasitic disease that most often affects the skin to cause disfiguring disease, appear to have a secret weapon, new research suggests: They can infect non-immune cells and persist in those uncommon environments.
Researchers found the Leishmania donovani parasites in blood-related stem cells in the bone marrow of chronically infected mice—precursor cells that can regenerate all types of cells in the blood-forming system. The finding may help explain why some people who develop visceral leishmaniasis, which is fatal if left untreated, often also have blood disorders such as anemia.
Identifying these cells and other unexpected locations in which these parasites live improves scientists’ understanding of the disease and may lead to new treatment options, said senior study author Abhay Satoskar, professor of pathology in The Ohio State University College of Medicine.
“Treating a patient with leishmania drugs never eliminates every parasite from the body—they persist for the rest of a patient’s life,” Satoskar said. “Perhaps these uncommon cells are the cells responsible for harboring these parasites in low numbers. Some drugs may not reach these cells properly or may not be effective with those parasites, and maybe the parasites in these kinds of cells are different compared to parasites in immune cells because they can adapt. It would be important to eliminate these hidden parasites if we want to stop the transmission of the disease.
“It changes the way we think about this parasite: If uncommon cells are infected, what is the cells’ role? What are the parasites doing there? How did they evade the drug treatment? Are they different from parasites in other cells, or the same? There are lots of questions.”
2023-09-29 14:00:05
Original from phys.org rnrn