Circulating CD4 and CD8 T cells expressing pro-inflammatory cytokines in a cohort of mesial temporal lobe epilepsy patients with hippocampal sclerosis

• mTLE patients showed reduced frequency of CD8+ T lymphocytes expressing IFN-γ, TNF-α.
• mTLE patients showed reduced frequency of CD8+ T lymphocytes expressing IL-17, IL-4.
• mTLE patients presented increased frequency of CD4+ T lymphocytes expressing IL-6.
• No difference was observed on the frequency of CD3+CD4+ and CD3+CD8+ T cells.

ObjectiveTo compare the proinflammatory and anti-inflammatory cytokine expression profile of CD4+ and CD8+ T lymphocytes between drug resistant mesial Temporal Lobe Epilepsy (mTLE) patients and healthy subjects.MethodsmTLE patients were enrolled at the Neurology Center of Santa Casa de Misericórdia de Belo Horizonte (SCM-BH) and healthy volunteers were selected at Universidade Federal de Minas Gerais. Individuals from both groups accepted to participate in this study and signed an informed consent. Peripheral venous blood samples were collected using sodium heparin vacuum tubes on the day before the surgery and in the interictal period, isolated from whole blood using Ficoll/Hypaque followed by flow cytometry analysis. Data analysis was performed using FlowJo.ResultsCompared to healthy individuals, mTLE patients showed reduced frequency of CD8+ T lymphocytes expressing IFN-γ, TNF-α, IL-17 and IL-4. Moreover, mTLE patients presented increased frequency of CD4+ T lymphocytes expressing IL-6 when compared to healthy volunteers.DiscussionEpilepsy is the third most common chronic brain disorder. Mesial temporal lobe epilepsy (mTLE) is a major and severe form of epilepsy and 30% of the mTLE patients do not respond to conventional medications. Our data suggest that mTLE patients have distinct immunological profiles that are related to disease pathophysiology.