Fig. 4

Human proBDNF from CSF AD patients induces apoptosis in neuronal culture. a) Representative pictures of neuronal primary culture from control mice Dentate Gyrus. Cells were treated for 6 days (7DIV) with human CSF from controls (control CSF) and from AD-affected patients (ADCSF). DAPI staining of nuclei shows apoptotic morphology (white arrow). Immunofluorescence with anti p75 ICD domain (green) and anti Sortilin (red). Inset indicate a higher magnification image of the boxed areas. White arrow in control CSF shows neurons with peripheral p75ICD location. White arrows in AD CSF show p75ICD nuclear location. b) Representative image of western blot showing the levels of proBDNF in CSF and in CSF immunodepleted with anti proBDNF (ID), from control and AD samples. c and d) Cells are treated with human 8 control CSF and 8 ADCSF, in both cases directly (CSF) or proBDNF immunodepleted (SCFID). c) Bars represent the quantification of apoptosis (by nuclei morphology), expressed as the mean of % apoptosis ± SD of the positive cells for both p75 and Sortilin. d) Bars represent the quantification of the mean of the % ± SD of neurons with the ICDp75 translocated to the nuclei (% ICD nuclear). Scale bar =50 μm . * p < 0,05, ** p < 0,01, two tailed Student’s “t” test