IL17A and Guillain-Barre syndrome: Previously we have also shown that both innate and adaptive lymphocytes contribute to upregulated production of IFN-γ, IL-17 and IL-22 after colitogenic isolate infection.20 In contrast, we found here that after GBS isolate infection, upregulation of IL-4 was mainly restricted to the CD4+ T cells at day 28 (Figure 3(a-c)).