Contributions to the study of Trichinella spiralis TSL‐1 antigens in host immunity

Abstract

The observation on different hosts infected with Trichinella spiralis that recognized similar muscle larvae (ML) antigens and the fact that different monoclonal antibodies (mAb) had a similar reactivity to ML components prompted a proposal to define a useful classification system for these antigens. For this purpose, an international workshop provided a platform for the classification of T. spiralis antigens. ML antigens were classified in eight groups -- Trichinella spiralis larvae groups, TSL-1 to TSL-8. TSL-1 antigens are highly immunogenic and a number of important studies have been performed to analyse the role of these antigens in the host-parasite interplay. In this context, we have focused on the analysis of the role of TSL-1 antigens in the induction of innate immune responses with particular emphasis on the activation of mast cells (MC) by an IgE-independent pathway. These studies provided evidence on the role of mediator release from TSL-1-activated MC in the development of Type 2 immune responses. The protective role of TSL-1 in T. spiralis-infected mice has been described. In addition, it has been demonstrated that the use of TSL-1 antigens allows for a more sensitive and specific diagnosis of human and animal trichinellosis.

Expulsion of Secondary Trichinella spiralis Infection in Rats Occurs Independently of Mucosal Mast Cell Release of Mast Cell Protease II

“…Rats maintain a resident population of mucosal mast cells in the lamina propria of the small intestine under homeostatic conditions (46). It has been suggested that mast cell activation might be a direct effect of the parasite, and such activation has been demonstrated in vitro following exposure of cultured mast cells to tyvelose-bearing T. spiralis Ags (47,48). In contrast, we found that parasite challenge in the absence of specific Abs did not cause significant RMCPII release.…”

Trichinella spiralis muscle larvae release extracellular vesicles with immunomodulatory properties

“…However, two issues, which were out of the scope of our current research, remain to be considered: the location of the detected ES L1 components, that is are they cargo, membrane or associated EVs proteins and the cellular origin of the detected EVs. Although helminth EVs may originate from the tegument, detection of ES L1 components within EVs suggests that their origin might be the stichosome, a multicellular organ that produces and releases ES L1 products …”

Secretory Products ofTrichinella spiralisMuscle Larvae and Immunomodulation: Implication for Autoimmune Diseases, Allergies, and Malignancies

“…contain some functional proteins such as proteinases, proteinase inhibitors, heat shock proteins, glycosidases, kinases, phosphatases, endonucleases, MIFs, enolases, and DNA-binding proteins [21], determined mostly according to their structural and sequence similarity to proteins from another species with known function. Since T. spiralis ES L1 antigens are localized on the surface of the parasite [22] and in the nuclei of infected host cells [23], a possible role of these molecules may be in invasion of the enterocytes, establishment or maintenance of the nurse cell, and induction of immune response in host organism [24]. …”