We have managed to characterize the PTM profile, specifically of ubiquitin and ISG15, in cerebral spinal fluids of different pathologies in the central nervous system (CNS). There is a great unmet need for putative biomarkers in neuroinflammation and therefore we decided to pursue this path which would have high commercialization potential. By examining patients' samples, extracted by spinal tapping, we collected 28 samples to be analyzed. Importantly, these samples were collected before diagnosis and therefore reflect an early disease stage. We collected samples from patients who were then diagnosed with Alzheimer's disease, Multiple Sclerosis, Relapsing-remitting, Glioblastoma, and Non-CNS conditions. We identified differential biomarkers across different diseases and others that were shared between all the neuroinflammatory states and were distinct from the non-CNS controls. For one of these biomarkers, we performed validation experiments, using an independent method, to confirm the results. We further continued to calibrate the relevant reagents to be able to scale the detection of said biomarker and also understand its potential role in neurodegeneration. Beyond the unmet need to identify novel biomarkers for neuroinflammatory conditions, the pathway we discovered may offer novel targets for therapeutic intervention.