OptimAb Neurofilaments, Hypophosphorylated , Monoclonal Antibody, purified

Blue ice

Neurofilaments are key components of the neuronsCytoskeleton whose main function is to provide structural support to the axons. There are 3 major neurofilament subunits: light or lowest (NF-L), medium or middle (NF-M) and heavy or highest (NF-H). While other anti-phosphoneurofilaments react with neurofilaments of high degrees of phosphorylation, SMI 35 reacts with neurofilaments of low degrees of phosphorylation as well. On 2D immumoblots, it detects a band extending from the phosphorylated neurofilament position at 200 kDa (pI 5.1) toward the non-phosphorylated position at 170 kDa (pI 6.2). It reacts primarily with NF-H and to a lower extent with NF-M in most mammalian species, as well as in chicken and frog (Xenopus). This antibody stains thick and thin axons and faintly stains cell bodies. It reveals an especially rich network of thin axons. Other cells and tissues are unreactive except for peripheral axons. In line with the low degree of neurofilament phosphorylation sufficient for reacion with SMI 35, more extensive phosphatase treatment of neurofilaments is necessary for abolition of reaction with this antibody than with any other antibody to phosphorylated neurofilaments. In pathological conditions, SMI 35 frequently detects early changes in neuronal cell body staining. A Golgi-like image of pathologic phosphorylation in neuronal perikarya and their dendritic arborizations has been obtained by ClonoPAP immunocytochemistry with SMI 35 providing a pre-chromatolytic, retrograde demonstration of neuronal connectivities. SMI 35 reacts with occasional intraneuronal tangles in Alzheimer's disease. This reaction increases in scope and degree with mild dephosphorylation but is abolished by extensive dephosphorylation.