Immunoregulation byTaenia crassicepsand Its Antigens

Abstract

Taenia crassiceps is a cestode parasite of rodents (in its larval stage) and canids (in its adult stage) that can also parasitize immunocompromised humans. We have studied the immune response elicited by this helminth and its antigens in mice and human cells, and have discovered that they have a strong capacity to induce chronic Th2-type responses that are primarily characterized by high levels of Th2 cytokines, low proliferative responses in lymphocytes, an immature and LPS-tolerogenic profile in dendritic cells, the recruitment of myeloid-derived suppressor cells and, specially, alternatively activated macrophages. We also have utilized the immunoregulatory capabilities of this helminth to successfully modulate autoimmune responses and the outcome of other infectious diseases. In the present paper, we review the work of others and ourselves with regard to the immune response induced by T. crassiceps and its antigens, and we compare the advances in our understanding of this parasitic infection model with the knowledge that has been obtained from other selected models.

Immunity and immune modulation elicited by the larval cestode Mesocestoides vogae and its products

“…However, dysregulated inflammatory responses might be analogically detrimental to the host . Consequently, chronic infections with a persisting antigen challenge often result in significant levels of immune hyporesponsiveness . As reported for the other cestode models, we showed that proliferation and IFN‐γ production in mitogen‐activated splenocytes is significantly suppressed during chronic infection.…”

“…As reported for the other cestode models, we showed that proliferation and IFN-c production in mitogen-activated splenocytes is significantly suppressed during chronic infection. Intriguingly, the suppression of lymphocyte proliferation by related larval cestodes occurred approximately 2 months after infection (2,33), while in our model, it was detectable already 3 weeks after infection. The observed differences could be due to the high invasive potential of M. vogae as compared to slowly developing above-mentioned cestodes.…”

Regulation of immunity by Taeniids: lessons from animal models and in vitro studies

“…Importantly, experiments show that reduced Th1/Th17 immune responses and enhanced Th2, MDSC and AAM populations induced by T. crassiceps are able to downmodulate experimental autoimmune encephalomyelitis , type 1 diabetes and acute‐severe DSS‐induced colitis model , in all cases inducing high levels of IL‐4 and IL‐10 but downregulating TNF‐α.…”

“…The observation that parasite antigens are able to mimic the effects of live parasite has led us to thoroughly investigate whether TcES is able to modify the outcome of autoimmune disease development in murine models of disease, as it happens to be a promising therapeutic alternative to actual anti‐autoimmunity drugs .…”

“…The Echinococcus spp and Taenia spp life cycles are similar to a degree, and both have been recently reviewed in detail ; thus, we do not address these topics in this review. Rather, we address Taeniids’ immunoregulatory strategies, discussing current and basic information mainly obtained from experimental laboratory models in the study of host–parasite interactions, as both Taenia spp and Echinococcus spp larval stages are well known to produce successful infections that can last for decades and tend to be relatively asymptomatic, suggesting the existence of a vast array of immunoregulatory mechanisms that allow for extended immunoregulation.…”