Mouse Monoclonal Antibody to α-Internexin Cat# MCA-1D2

      α-internexin is a Class IV intermediate filament protein originally discovered by two different groups of researchers as it copurifies with NF-L, NF-M and NF-H, the better known major neurofilament "triplet" subunits (1,2). It is expressed only in neurons and in large amounts early in neuronal development, but is down-regulated in many neurons as development proceeds. Some neurons express α-internexin in the absence of NF-L, NF-M and NF-H, though most mature neurons express all four proteins. α-internexin antibody has been shown, in peer reviewed publications, to reveal the upregulation of α-internexin in facial neurons following experimental axotomy followed by down regulation on axonal regeneration (3). It has also been used to identify and classify patients with neurofilament inclusion body disease, a specific form of frontotemporal lobar dementia (4-6). Finally it can be used to confirm the presence of circulating antibodies to α-internexin in the blood of certain patients with endocrine autoimmunity (7).

Chromogenic immunostaining of a 4% PFA fixed paraffin embedded rat cerebellum section with mouse mAb to α-internexin, MCA-1D2, dilution 1:1,000, detected in DAB (brown) following the Vector Labs immPRESS® method with citra retrieval. Hematoxylin (blue) was used as the counterstain. The 1D2 α-internexin antibody labels parallel fibers and other neuronal processes in both rat and human brain. This antibody performs well in testing with both 4% PFA and standard NBF fixed tissues but does not stain long term NBF fixed tissue effectively. We therefore recommend our alternate mouse monoclonal antibody to α-internexin MCA-2E3 for such paraffin applications. Mouse select image for larger view.

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3. McGraw T. et al. Axonally transported peripheral signals regulate alpha-internexin expression in regenerating motoneurons. J Neurosci. 22:4955-63 (2002).
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Screening for neurofilament inclusion disease using alpha-internexin immunohistochemistry. Neurology 64:1658-9 (2005).
7. Rajasalu T, et al. Demonstration of natural autoantibodies against the neurofilament protein alpha-internexin in sera of patients with endocrine autoimmunity and healthy individuals. Immunol. Lett. 94:153-60 (2004).