Letter to the Editor: Inhibition of cytokine production in Gastro-allergic Anisakiasis and Anisakis simplex sensitization-associated chronic urticaria

Abstract

We read with interest the article ‘‘Different Th1⁄Th2responses to Anisakis simplex (A.s.) are related to distinctclinical manifestations in sensitized patients’’(1).Theauthors analyse cytokine production with crude extract(CE) and thermostable extract in patients with specific IgEagainst A.s. By finding a similar cellular response to bothextracts, they come to the conclusion of the possibility ofrisk when these patients eat cooked or frozen fish: To ourunderstanding, this statement is not based on allergologicalconcepts, where neither the detection of specific IgE northe cellular response to different allergens is equivalent toovert allergic symptoms. Further, in the special case ofGastro-allergic Anisakiasis, it has been shown that not onlyexcretory secretory products are responsible for the allergicreaction, but also these have to be delivered by the livelarva of A.s. when penetrating the gastric mucosa (2,3).On the other side, we analysed with interest their table 2about the values of different cytokines when stimulatedwith mitogen versus A.s. crude extract (CE). In a similarevaluation of 23 patients with A.s. sensitization-associatedurticaria (10 patients with Gastro-allergic urticaria and 13with A.s. sensitization-associated chronic urticaria), wecompared the induction of cytokines by A.s.CE as well asConcanavalin A (ConA)-stimulated peripheral bloodmononuclear cells (PBMC) by the same cytometric beadarray kit (CBA; BD Biosciences, Madrid, Spain). Weobserved lower levels of IL6, IL-10, IL-17, TNF and IFNin CE than in ConA-stimulated PBMC (all p< 0,01). Onthe other side, IL-2, a cytokine important for growth andsurvival of Th1 and Th2 subsets showed by far higher val-ues when stimulated with CE (p= 0,02), underlining thepotency of the used extract and proving the specific stimu-lation of patient cells which guaranties the induction ofimmunological responses. Thus, the lower values for theother cytokines can be interpreted as inhibition.Even if differences in the extract preparation, the con-centrations or mitogen used make difficult a direct com-parison, similar results seem to be present in the study byGonzlez-MuCoz et al. as shown in their table 2, but nointerpretation of these has been performed. Differentialcytokine production is one of the many mechanisms pro-posed to play a role in modulating the host response byhelminth parasites (4). Here, the results demonstrate thata past A.s. infection is able to modulate not only Th1-and Th2-related cytokines, but also the pro-inflammatoryIL-6, IL17 cytokines and the release of IL-10, as shownby stimulation with A.s.CE. We are currently analysingwhether TGF-b could be responsible for the A.s- inducedcytokine inhibition.This work was funded by grants from FundacinSEAIC and Fundacin Mutua MadrileCa.