Helminthic therapy and organ transplantation

⚭Home>Effects of helminthic therapy>Helminthic therapy and organ transplantation

Pathogenic helminths may present a risk for organ transplant patients, and three possible scenarios are mentioned in the literature.

• a helminth infection acquired from the donated organ, [1]
  
• a latent helminth infection reactivated as a result of post-transplantation immunosuppression, [2]
  
• a new helminth infection acquired during the immunosuppressed post-transplantation period.
  

However, it appears unlikely that hosting any of the currently available therapeutic helminths will present a threat to a transplant recipient.

… regardless of whether the transplanted organ was the point of entry of the helminth into the recipient or the helminthiasis was a consequence of the subsequent immunosuppression, only those helminths capable of multiplying in human beings—thus increasing their number—and able to invade various organs and tissues are, in my opinion, relevant and deserve special attention. Therefore, in this sense, the only helminthiasis that constitutes a serious threat to transplant recipients is strongyloidiasis. The only other helminth capable of multiplying in people is the tapeworm Hymenolepis nana but, unlike Strongyloides stercoralis, H. nana is exclusively an intestinal parasite that does not reach any other location. [3]

Moreover, it is possible that a therapeutic helminth infection might assist in suppressing rejection of a transplanted organ.

The results show that helminth-derived products can powerfully induce regulatory immunological mechanisms in the presence of a fully allogeneic transplant. Identification of the specific mechanisms involved in suppression of allograft rejection by helminth parasites could lead towards development of safe and effective novel therapeutic strategies. [4]

As well as acting as novel immune regulators or adjuncts for the prevention of allograft rejection, [5] helminths may also provide protection against graft-versus-host disease following bone marrow transplantation. [6]

The scientific evidence

• 2023 Jun 9 After Bone Marrow Transplantation, the Cell-Intrinsic Th2 Pathway Promotes Recipient T Lymphocyte Survival and Regulates Graft-versus-Host Disease -- Full text | PDF
• 2020 Aug 7 Effectiveness of Helminth Therapy in the Prevention of Allograft Rejection: A Systematic Review of Allogeneic Transplantation -- Full text | PDF
• 2017 Jun Helminths in organ transplantation
• 2015 Jul Exploration of helminth-derived immunoregulatory molecules as options for therapeutic intervention in allograft rejection and autoimmune disease -- PDF (Thesis)
• 2015 Feb 26 A role for helminth parasites in achieving immunological tolerance in transplantation
• 2014 Jan 27 Helminths and Immunological Tolerance -- Full txt | PDF
• 1996 Jan 27 Prolongation of rat kidney allograft survival by nematodes

See also

• 2025 Sep 17 Unique Immune Polarization of the Lung Allograft: Implications for Organ-specific Immunoregulation and Tolerance Induction
• 1993 May Oral, but not intravenous, alloantigen prevents accelerated allograft rejection by selective intragraft Th2 cell activation

See also

• Helminthic therapy and graft-versus-host disease (GVHD)

The reintroduction to the digestive tract of a controlled number of specially domesticated, mutualistic helminths (intestinal worms) in the form of microscopic eggs or larvae to reconstitute a depleted biome to treat or prevent chronic inflammation, autoimmune disease and other immune-related disorders, including allergy.

An intestinal worm which grows large enough to be seen with the naked eye when mature but which is microscopic when administered in helminthic therapy. Wikipedia:Helminths

An intestinal worm which grows large enough to be seen with the naked eye when mature but which is microscopic when administered in helminthic therapy. Wikipedia:Helminths

A helminth with a flat, ribbon-like, segmented body. Only the murine (rat) tapeworm, Hymenolepis diminuta, is used in helminthic therapy and this generally does not reach adulthood in humans so requires regular dosing of HDC.

A species of murine (rat) tapeworm closely related to Hymenolepis diminuta but not suitable for use in therapy because it can reproduce within a host and spread person-to-person. Also known as Dwarf tapeworm.

The roundworm that causes strongyloidiasis and is known as 'pinworm' in the UK and 'threadworm' in the US. Infection with S. stercoralis can be fatal.

A species of murine (rat) tapeworm closely related to Hymenolepis diminuta but not suitable for use in therapy because it can reproduce within a host and spread person-to-person. Also known as Dwarf tapeworm.

An organism that lives in or on another organism (its host) and benefits at the host’s expense. (The organisms used in helminthic therapy are, strictly speaking, not parasites, but mutualists, because they have a mutually beneficial symbiotic relationship with their hosts.)

An organism that lives in or on another organism (its host) and benefits at the host’s expense. (The organisms used in helminthic therapy are, strictly speaking, not parasites, but mutualists, because they have a mutually beneficial symbiotic relationship with their hosts.)