LR performed, analyzed and interpreted the circulation cytometry analysis. addition, MSCs inhibited the M1 phenotype of the microglia. However, edema of the explants was observed in presence of MSCs, with an increase in fibronectin labeling at the surface of the explant corresponding to an epiretinal membrane-like phenotype. Summary Using an ex vivo neuroretina model, we shown a neuroprotective and immunomodulatory effect of MSCs on RGCs. Unfortunately, the presence of MSCs also led to explant edema and epiretinal membrane formation, as explained in human tests. Using the MSC PDGFB secretome might offer the beneficial effects of MSCs without their potential adverse effects, through paracrine signaling. Supplementary Info The online version contains supplementary material available at 10.1186/s12974-022-02418-w. and indicated as RGC/306 m2 or percentage of cells compared to Days Ex lover Vivo (DEV) 0. Concerning quantification in transverse sections, sections were taken throughout the whole explant, with approximately 18 slides/explants, allowing placement of different areas of the explant on the same slide. Three images were acquired per section, in five different sections on a slip. RGC or displaced amacrine cells (DAC) quantification was indicated as RGC/mm or DAC/mm. For GFAP, Iba1 6-Thioinosine and CD68 immunostaining quantification, explant cryosections were taken using an epifluorescence microscope (Zeiss AX-10). Three images were acquired for each explant using a?10 or?20 objective and the same parameters of time exposure for each explant. NIH Image J software was then used to quantify the Uncooked Integrated Denseness of each section, allowing us to obtain the sum of pixels ideals. For all images, Background values have been subtracted of Natural Integrated Density and the same area was selected. Sections were analyzed inside a blinded manner; the experimenter was blinded to the treatment. Quantitative RT-PCR Total RNA of 6C16 retinal explants per group (3?mg/explant) was purified using the NucleoSpin RNA XS kit (MachereyCNagel, ref. 740902.50) according to protocol. Total RNA was reverse-transcribed into cDNA a High Capacity RNA to cDNA kit (Life Systems, ref. 4368814) according to the manufacturers instructions. Real-time PCR was performed using the TaqMan Gene Manifestation PCR Master blend (Applied Biosystems, ref. 4324020) and the Applied Biosystem Fast 7500 (Applied Biosystems). The 6-Thioinosine deltaCdelta method (ddtnegative control in gray), percentages of positive cells and mean fluorescence intensities are offered in the Additional file 1. RGC degeneration inside a retinal explant tradition model The best restorative windowpane to assess neuroprotection was determined by evaluation of RGCs degeneration following optic nerve axotomy in the retinal explant tradition model, which can vary between laboratories, handlers, or tradition conditions. Brn3a and RBPMS specific RGCs markers were utilized for RGCs counting from Day 6-Thioinosine ex lover vivo (DEV) 0C7 (Fig.?1ACD) [34, 35]. Loss of RGCs occurred with both markers after 24?h of tradition but without significance. The number of RGCs was statistically different at DEV 3 and later on compared to DEV 0 for Brn3a quantification (44% RGCs death at DEV 3 from DEV 0, mesenchymal stem cell, ganglion cell coating, inner plexiform coating, inner nuclear coating, outer plexiform coating, outer nuclear coating, outer segments, insert membrane. C Retinal explant thickness measurement. Each pub is the imply??SEM. em n /em ?=?4C6/group. Regular one-way ANOVA was performed. **** em P /em ? ?0.0001 Conversation Over the last decade, there has been increasing desire for the use of stem cells, including retinal progenitor cells (RPCs), embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and MSCs to regenerate RGCs in glaucoma [40]. MSCs have also demonstrated neuroprotective and immunomodulatory properties. They have the advantages of demonstrating immunosuppressive effects and are less immunogenic and tumorigenic than ESCs. Compared with harvesting RPCs, it is relatively easy to obtain MSCs, and they possess a higher proliferative capacity [2]. The iPSCs 6-Thioinosine strategy is also interesting, as these cells have the potential for reducing immunogenicity through autologous transplantation, but iPSCs have a lower variable differentiation effectiveness and.