Mannan-binding lectin (MBL) data in an IgM Reibergram. The CSF/serum quotients QMBL are shown as a function of the albumin quotients, QAlb, in a diagram with the upper limit for the IgM molecule shown by the bold curve and with the reference range for the IgM molecule which has a similar molecular size as MBL. The filled squares represent the data of normal controls and the open circles of patients with a barrier dysfunction in the absence of an intrathecal immune response. 9/13 controls are obviously above the upper limit of the reference range, i.e., they have an intrathecal MBL fraction over 80% of total CSF MBL in addition to the blood-derived MBL fraction. The largest QMBL values correspond to the lowest serum MBL values (Table 1). For explanation of the diagram see legend to Figure 1 and . The diagram was created with the CSF Statistics Tool .