Excretory/secretory products of anisakid nematodes: biological and pathological roles

Abstract

Parasites from the family Anisakidae are widely distributed in marine fish populations worldwide and mainly nematodes of the three genera Anisakis, Pseudoterranova and Contracaecum have attracted attention due to their pathogenicity in humans. Their life cycles include invertebrates and fish as intermediate or transport hosts and mammals or birds as final hosts. Human consumption of raw or underprocessed seafood containing third stage larvae of anisakid parasites may elicit a gastrointestinal disease (anisakidosis) and allergic responses. Excretory and secretory (ES) compounds produced by the parasites are assumed to be key players in clinical manifestation of the disease in humans, but the molecules are likely to play a general biological role in invertebrates and lower vertebrates as well. ES products have several functions during infection, e.g. penetration of host tissues and evasion of host immune responses, but are at the same time known to elicit immune responses (including antibody production) both in fish and mammals. ES proteins from anisakid nematodes, in particular Anisakis simplex, are currently applied for diagnostic purposes but recent evidence suggests that they also may have a therapeutic potential in immune-related diseases.

Analysis of Ani s 7 and Ani s 1 allergens as biomarkers of sensitization and allergy severity in human anisakiasis

“…Fourteen A. simplex allergens have been described and classified in three groups according to its origin: excretory/secretory, somatic and cuticular proteins 7 , 17 , 26 – 28 . The first group includes relevant major allergens as Ani s 1 and Ani s 7, which are frequently used to measure sIgE responses to A. simplex in different populations including non-symptomatic blood donors, fish processing workers and patients suffering gastroallergic anisakiasis or chronic urticaria 9 , 17 , 29 .…”

Mass Spectrometry Based-Proteomic Analysis of Anisakis spp.: A Preliminary Study towards a New Diagnostic Tool

“…ES molecules are responsible for a multitude of functions during infection, such as penetration of host tissues and evasion of host immune responses, and at the same time are known to elicit immune responses. Therefore, ES proteins are hypothesized to be the major contributors in clinical manifestation of the disease in humans [ 28 ].…”

The self‐curing phenomenon of schistosome infection in rhesus macaques: insight from in vitro studies

“…Interestingly, we observed a significant increase in the magnitude of the response of B cells stimulated with SmEA or SmWA+SmEA compared with B cells stimulated with SmWA only (from all tissues examined; PBMCs, LN, and gut LPLs), consistent with the hypothesis that antibody‐mediated schistosome killing in infected macaques maybe be associated with the onset of egg‐laying by the female worms. The contributions of parasite‐derived excretory–secretory products in mounting protective responses have been reported in other parasite systems …”

“…The contributions of parasite-derived excretory-secretory products in mounting protective responses have been reported in other parasite systems. 39,40 NK cells have been shown to play antifibrotic roles in both artificial models of liver fibrosis and animal models of schistosome-infection. 41,42 The possible role(s) of CD8 + NK cell-mediated antibody-dependent cell-mediated cytotoxicity in the self-cure process in rhesus macaques is not known.…”