Certain cats are the host for an intestinal roundworm called Toxoplasma gondii. Adult worms live in the cat’s intestines and reproduce by releasing eggs into the cat’s feces. When humans are infected by inadvertently ingesting the infective oocysts (for example children sometimes put things in their mouths that they shouldn’t), the victim’s immune system springs into action producing natural killer cells and cytotoxic T cells. These destroy the parasite. Most people don’t even know they have the parasite while others develop flu-like symptoms. Researchers hope to use this same response to fight cancer.
Dr. David Bzik and Barbara Fox from the department of microbiology and immunology, Geisel school of Medicine at Dartmouth developed a vaccine made from T. gondii. The pair used a genetically altered form of the parasite called “cps” that cannot replicate yet still causes the immune reaction when given to humans. Because of this modification, the cps vaccine would be safe even for people with suppressed immune systems. So far, the vaccine has shown great success in laboratory mice with aggressive forms of melanoma and ovarian cancer.
The ultimate goal is to create a vaccine tailored to the patient. Dr. Bzik hopes to remove cancer cells from a patient, infect them with cps and then reintroduce the cells. This will stimulate the patient’s immune system to target the cancer and hopefully, cure the patient.
Source: -Does cat poop parasite play a role in curing cancer? Norris Cotton Cancer Center Dartmouth-Hitchcock Medical Center, SCIENCEDAILY, July 15, 2014. www.sciencedaily.com/releases/2014/07/140715095515.htm.