T cell clones in human trichinellosis: evidence for a mixed Th1/Th2 response

In humans, studies on the cellular immune response against Trichinella are scarce. Aim of this study was to characterize the cytokine profile of T cells specific for Trichinella britovi in trichinellosis patients. PATIENTS AND METHODS: Peripheral blood mononuclear cells (PBMC) were obtained from five patients involved in a trichinellosis outbreak caused by Trichinella britovi, which occurred in 2013 in Tuscany (Italy). All the patients resulted positive for Trichinella-specific IgG, IgE and presented eosinophilia. T cells were investigated for their proliferation to excretory/secretory antigens from T. spiralis muscle larvae (TsES) and for their cytokine profile. RESULTS: 284 CD4+ and 42 CD8+ T-cell clones were obtained from the TsES-specific T cell lines from PBMC. All T-cell clones proliferated in response to mitogen. Of the 284 CD4+ T-cell clones generated from TsES-specific T-cell lines, 135 (47%) proliferated significantly to TsES. 26% CD8+ T cell clones showed proliferation to TsES. In the series of the 135 TsES-specific CD4+ clones, 51% expressed a Th2 profile, 30% a Th0, and 19% Th1. In the series of the 11 TsES-specific CD8+ T cell clones, 18% were Tc2, 45% Tc0, and 36% Tc1. CONCLUSION: In human trichinellosis, the cellular immune response is, during the chronic phase, mixed Th1/Th2. This article is protected by copyright. All rights reserved.