CD40LG and Lyme disease: However, CSF analysis revealed lymphocytic pleocytosis (145 cells/μl with 85% lymphocytes, 2% plasma cells, 11% monocytes, and 2% neutrophils; Figure 4a), elevated total protein (1911 mg/l) and lactate (3.36 mmol/l), severe blood-CSF barrier dysfunction (Q-Albumin 30.0*10-3, i.e. 3.5 times the upper age-related reference limit), and intrathecal synthesis of IgG and IgM (but not IgA) according to Reiber's formula (IgG, 30% and IgM, 54%), a pattern highly suggestive of neuroborreliosis that was confirmed serologically (IgG antibody index 33.5).