Normal intrathecal leukocyte cell number and composition do not decrease the incidence of post–lumbar puncture headache

The pathogenesis of post-lumbar puncture headache (PLPH) has remained unclear. A beneficial role of CSF cells in the repair of a post-traumatic dural CSF leak has been suggested. The primary purpose of this study was to investigate the effects of 8weeks of induction therapy with high-dose PF-00547659 on the cellular elements of CNS immune surveillance in patients with active Crohn's Disease and a history of immunosuppressive therapy (Clinicaltrials.govNCT01387594). PF-00547659 is a human monoclonal antibody that binds to mucosal addressin-cell adhesion molecule 1 (MAdCAM-1) on endothelial cells and blocks its interaction with beta7-integrin expressing lymphocytes. The study was executed in three parts or cohorts under two protocols. The incidence of a PLPH was 35% after the initial lumbar puncture, and 26% following the second lumbar puncture. After initiation of PF-00547659 anti-MAdCAM-1 therapy, there was a small and non-significant increase in the numbers of overall CSF leukocytes, and in lymphocyte subsets (CD3+, CD4+, and CD8+ T cells). The lymphocyte composition was unaltered by PF-00547659 anti-MAdCAM-1 therapy. Our observations suggest that normal numbers and composition of intrathecal leukocytes do not decrease the incidence of PLPH.