Other markers include Monocyte Chemoattractant Protein-1 (MCP-1), which is detected both in CSF and blood and increased levels have been found in a variety of NDD where they are often related to disease progression, and CNS myeloid cell infiltration (Singh et al., 2021); this protein is secreted by myeloid cells, but also other CNS and BBB cells and attracts myeloid cells from the periphery to the CNS aiding in the movement of cells within the CNS (Yao and Tsirka, 2014). Here, CCL2 is linked to Neurodevelopmental delay.