Neurofilaments are intermediate filaments that form the neuronal cytoskeleton together with microtubules. There are five human genes that make up neurofilament heteropolymers; they include NEFL (low molecular weight), NEFM (medium), and NEFH (high), as well as the neuronal intermediate filament proteins peripherin and internexin. Neurofilaments act as structural space-fillers for axons and are also involved in axonal transport. Antibodies that detect multiple neurofilament proteins are regularly used to identify neurons and distinguish them from glia (neurofilament-negative) and for diagnosis in neuropathology. Because neurofilaments are released into the blood when axons and neurons deteriorate, antibodies to neurofilaments are also used to observe the progression and state of neurodegenerative diseases such as multiple sclerosis and Huntington’s disease. In immunohistochemistry, antibodies to neurofilaments highlight axons of neuronal cells in the central nervous system and in peripheral nerves, and may also show positivity in prostate glandular cells. References: European Journal of Neurology. 2010 Mar. 17 (3): 377–8, PMID: 19845747; Neurology. 2009 Apr. 72 (15): 1322–9, PMID: 19365053; PLOS One. 2017 Feb. 12 (2): e0172762, PMID: 28241046; Garland Science. ISBN: 978-0-8153-3218-3.