Fig. 2

Demonstration of the immunomodulating and neuroprotective secretome of BM-MNC in vitro and generation of biohybrid electrode arrays. a Proteomic analysis of bone marrow supernatant. Immediately after centrifugation of the bone marrow, the BM-MNC-containing plasma supernatant was obtained and stored ice-cold until proteomic analysis. Different cytokines, chemokines, and growth factors were present at biologically relevant concentrations in the supernatant. Among these, factors that promote wound healing and modulate and control neuroinflammation were identified. b Neuroprotective effect of BM-MNC. Surviving spiral ganglion neurons (SGN) were quantified for each treatment condition and compared to the medium (serum-free culture medium; neg. control) and to the positive control (medium supplemented with BDNF; pos. control). Supernatant was obtained immediately after centrifugation of bone marrow using the RegenKit-THT tubes from each patient. The term BM-MNC denotes the mononuclear cell fraction re-suspended in supernatant. Conditioned medium was obtained after 24 or 48 h (cond. med. 24/48) cultivation of the BM-MNC solution in serum-free culture medium. When compared to the negative control, significantly increased survival was determined in the positive control as well as after treatment with conditioned medium. c, d Biocompatibility of fibrin adhesive tested in well-established in vitro culture assays. Human MPC and SGN isolated from rodents were treated with fibrin adhesive and the survival was compared to the positive control (medium supplemented with BDNF) as well as to cultivation in medium without supplements (neg. control). Cell survival was not altered in the presence of fibrin adhesive when compared to the medium control. Values are presented as the mean with standard deviation. *p < 0.1, **p < 0.01, ***p < 0.001. FGF fibroblast growth factor, MNC mononuclear cells, MSC mesenchymal stem cells, ns not significant