Neurofilament light polypeptide

These form heteropolymers which assemble to produce 10 nm neurofilaments which are only expressed in neurons where they are major structural proteins, particularly concentrated in large projection axons.

The detection of neurofilament subunits in CSF and blood has therefore become widely used as a biomarker of ongoing axonal compromise.

[5][6] Neurofilament light chain is a biomarker that can be measured with immunoassays in cerebrospinal fluid and plasma and reflects axonal damage in a wide variety of neurological disorders.

[14] Higher levels of blood or CSF NF-L have been associated with increased mortality, as would be expected as release of this protein reflects ongoing axonal loss.

[16] Methods used in different studies for NfL measurement are sandwich enzyme-linked immunosorbent assay (ELISA), electrochemiluminescence, and high-sensitive single molecule array (SIMOA).

Rat brain cells grown in tissue culture and stained, in green, with an antibody to neurofilament subunit NF-L, which reveals a large neuron. The culture was stained in red for α-internexin, which in this culture is found in neuronal stem cells surrounding the large neuron.
A formalin fixed and paraffin embedded section of human cerebellum stained with an antibody to NF-L revealed with a brown dye, cell nuclei are revealed with a blue dye. Nuclear rich region at left is granular layer, region at right is molecular layer. The antibody binds processes of basket cells, parallel fiber axons, the perikarya of Purkinje cells and various other axons.