Lymphocyte subsets in pediatric migraine

Aseptic inflammation due to activated immune cells has been implicated in the pathomechanism of migraine. We measured the prevalence of regulatory T cells (Tregs), along with that of CD4⁺/CD8⁺ lymphocytes and their Th1/Th2 commitment in pediatric migraine. Children and adolescents suffering from migraine without aura, migraine with aura and hemiplegic migraine ictally (n = 53, 27, and 20, respectively), also interictally (n = 33) were recruited and compared to 24 healthy children. Our results indicated comparable prevalence of Tregs, CD4⁺ and Th1/Th2 committed cells. CD8⁺ prevalence was lower, and CD4⁺/CD8⁺ ratio was higher in ictal phase irrespective of the subtype of migraine. No association between CD8⁺ prevalence and gender, body weight, disease onset and attack duration in migraine subtypes was found. CD8⁺ prevalence was normal in patients in interictal phase. These results suggest the absence of major systemic alteration of adaptive immunity in children and adolescents suffering from migraine; however, a transient decrease of CD8⁺ prevalence during the ictal phase was detected irrespective of the subtype of migraine.