Trichuris muris and comorbidities - within a mouse model context

Abstract

Trichuris muris is a mouse intestinal parasitic nematode that inhabits the large intestine of its host and induces a strong immune response. The effects of this strong anti-parasite response can be found locally within the intestinal niche and also systemically, having effects on multiple organs. Additionally, the anti-parasite response can have multiple effects on infectious organisms and on microbiota that the host is harbouring. It has been shown that Th1 responses induced by T. muris can affect progression of bowel inflammation, cause colitic-like intestinal inflammation, reduce barrier function and intestinal mucosal responses. In the brain, T. muris can exacerbate stroke outcome and other neurological conditions. In the lung, T. muris can suppress airway inflammation and alter immune responses to other parasites. Additionally, T. muris induced responses can inhibit anti-tumour immunity. Although this parasite maintains a localized niche in the large intestine, its effects can be far-reaching and substantially impact other infections through modulation of bystander immune responses.

Keywords: Trichuris muris; cancer; co-infections; comorbidity.

Graphical abstract

Fig. 1.

The whipworm T. muris, though caecal dwelling, can affect many other systems in the body. The immune response to T. muris is dose-dependent with different cytokines being produced in response to the different doses of eggs given which can lead to chronic infection (Th1) or expulsion (Th2). Each of the immune responses to the differing doses of eggs can impact different systems in the body as depicted by the arrows. As pictured, tumours are increased in size and number in a cancer model with chronic T. muris, pathology is increased in chronic infection and shows similarity to IBD, and hippocampus RANTES expression is increased with chronic T. muris infection. Changes in microbiota, lung effects and effects on other infections are also apparent with T. muris infection. (Created with BioRender.com)