Whipworm ova (Trichuris suis) and hookworm (Necator americanus) have been tested for immunological diseases and allergies, and have proved beneficial on multiple fronts, yet it is not entirely understood. Scientists have found that the immune response triggered by the burrowing of hookworm larvae to pass through the lungs and blood so the production of mast cells and specific antibodies are now present. They also reduce inflammation or responses ties to autoimmune diseases, but despite this, the hookworm's effects are considered to be negative typically.[1] Helminthic therapy has been investigated as a treatment for relapsing remitting multiple sclerosis, Crohn's, allergies and asthma. While there is much to be learned about this, many researchers think that the change in the immune response is thanks to the parasites shifting to a more anti-inflammatory or regulatory system, which would in turn decrease inflammation and self inflicted immune damage as seen in Crohn's and multiple sclerosis. Specifically, MS patients saw lower relapse rates and calmer symptoms in some cases when experimenting with helminthic therapy.[2] Hypothesized mechanisms include re-polarisation of the Th1 / Th2 responseand modulation of dendritic cell function. The helminths downregulate the pro-inflammatory Th1 cytokines, interleukin-12 (IL-12), interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α), while promoting the production of regulatory Th2 cytokines such as IL-10, IL-4, IL-5 and IL-13.

Co-evolution with helminths has shaped some of the genes associated with interleukin expression and immunological disorders, such Crohn's, ulcerative colitis and celiac disease. Helminths' relationship to humans as hosts should be classified as mutualistic or symbiotic. In some ways, the relationship is symbiotic because the worms themselves need the host (humans) for survival, because this body supplies them with nutrients and a home. From another perspective, it could be reasoned that it is mutualistic, being that the above information about benefits in autoimmune disorders continues to remain true and supported. Also, some say that the worms can regulate gut bacteria.[3] Another possibility is one of this being a parasitic relationship, arguing that the possibile rosks of anemia and other disorders outweighs the benefits, yet this is significantly less supported, with the research alluding to the mutualitic and symbiotic approach being much more likely.

  1. ^ Loukas, Alex (October 2001). "Immune Responses in Hookworm Infections". PubMed.
  2. ^ Donkers, Sarah (Jan-Feb, 2020). "Perspectives of People with Multiple Sclerosis About Helminth Immunotherapy". PubMed. {{cite web}}: Check date values in: |date= (help)
  3. ^ Loke, P'ng (June 1, 2016). "Helminths and the microbiota: parts of the hygiene hypothesis".