Increased susceptibility toStrongyloides venezuelensisin mice due toMycobacterium bovisco-infection which modulates production of Th2 cytokines

Abstract

An estimated quarter of the world's population possesses an infection caused by gastrointestinal nematodes, which induce a Th2 type immune response. Concomitant infection of nematodes with Mycobacterium tuberculosis, which induces a predominantly Th1 type response, is very frequent in tropical and subtropical regions. This study examined immune responses of BALB/c mice infected with Strongyloides venezuelensis and then co-infected with Mycobacterium bovis. The number of worms in the intestine, eggs in feces, cytokine production in lungs and intestine and the expression of CD80, CD86, CTLA-4 and CD28 cell markers on pulmonary cells were analysed. Our results indicate that co-infected mice had an increased parasite burden, which correlates with elevated IFN-gamma and IL-10 cytokine production and decreased IL-4 and IL-13. Moreover, decreased expression of CD80 and increased expression of CTLA-4 were observed in co-infected mice. Our data point out that susceptibility to Strongyloides venezuelensis infection is increased by Mycobacterium bovis co-infection, resulting in higher parasite survival.

Mycobacterium bovis BCG infection severely delays Trichuris muris expulsion and co-infection suppresses immune responsiveness to both pathogens

“…In parallel with this we observed an increase in intestinal mucus production, which likely operates as a compensatory mechanism to aide expulsion of persisting parasites. Our results verify reports illustrating that M. bovis co-infection increase helminth parasite burden and correlates with decreased IL-4 and IL-13 cytokine production [41]. Our findings also agree with early reports demonstrating a reduction in protective immune responses and a delay in T. muris expulsion during other co-infections with Nematospiroides dubius , Plasmodium berghei or Trypanosoma brucei [42-44].…”

Lower production of IL-17A and increased susceptibility to Mycobacterium bovis in mice coinfected with Strongyloides venezuelensis

“…The number of eggs was higher in the CI group (65.4 ± 11.51) in comparison to the Sv group (37.5 ± 6.72). The results are statistically significant (p < 0.05) and are consistent with previously reported results by Carmo et al (2009).…”

Helminth–microparasite co‐infection in wildlife: lessons from ruminants, rodents and rabbits

“…Microparasites can also have profound effects on worm infections . The consequences of HIV infection for worms have captured particular attention in this regard owing to the known immunosuppressive effects of HIV .…”

“…Microparasites can also have profound effects on worm infections. [35][36][37] The consequences of HIV infection for worms have captured particular attention in this regard owing to the known immunosuppressive effects of HIV. 38 As one example, reductions in The potential to do this in wild animals is highlighted by studies of another immunosuppressive virus (myxoma virus) and its effects on gastrointestinal worm infections in free-ranging European rabbits (Oryctolagus cuniculus; Fig.…”