Anti-GFAP (Cocktail) (Previously Covance catalog# SMI-22R)

Pricing & Availability
SMI 22 (See other available formats)
Other Names
Glial fibrillary acidic protein
Covance Catalog# SMI-22R
Mouse IgG2b
Ave. Rating
1 reviews
Product Citations
Immunostaining of the SMI 22 antibody (green) on rat brain (8 µm horizontal section). Other structures visualized with anti-NFH (red, Cat. No. 822501) and Hoechst. Photo courtesy of Molecular Expressions.
  • SMI22_GFAP_Cocktail_1_IF_022015.jpg
    Immunostaining of the SMI 22 antibody (green) on rat brain (8 µm horizontal section). Other structures visualized with anti-NFH (red, Cat. No. 822501) and Hoechst. Photo courtesy of Molecular Expressions.
  • SMI22_GFAP_Cocktail_2_IF_022015.jpg
    Immunostaining of the SMI 22 antibody (green) on rat brain (8 µm horizontal section). Other structures visualized with anti-NFH (red, Cat. No. 822501) and Hoechst. Photo courtesy of Molecular Expressions.
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835301 100 µl $264
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Glial fibrillary acidic protein is an intermediate filament (IF) protein that is expressed by numerous cell types of the central nervous system (CNS) including astrocytes and ependymal cells. GFAP has also been found to be expressed in glomeruli and peritubular fibroblasts, Leydig cells of the testis, keratinocytes, osteocytes and chondrocytes and stellate cells of the pancreas and liver. GFAP is a type III IF protein that is closely related to its non-epithelial family members, vimentin, desmin, and peripherin, which are all involved in the structure and function of the cell’s cytoskeleton. GFAP is thought to help to maintain astrocyte mechanical strength, as well as the shape of cells.

Type III intermediate filaments are highly conserved and contain three domains, named the head, rod and tail domains. This rod domain coils around that of another filament to form a dimer, with the N-terminal and C-terminal of each filament aligned. Type III filaments such as GFAP are capable of forming both homodimers and heterodimers; GFAP can polymerize with other type III proteins or with neurofilament protein (NF-L). Interestingly, GFAP and other type III IF proteins cannot assemble with keratins, the type I and II intermediate filaments: in cells that express both proteins, two separate intermediate filament networks form.

To form networks, the initial GFAP dimers combine to make staggered tetramers, which are the basic subunits of an intermediate filament. The non-helical head and tail domains are necessary for filament formation. The head and tail regions have greater variability of sequence and structure. In spite of this increased variability, the head of GFAP contains two conserved arginines and an aromatic residue that are required for proper assembly.

Product Details
Technical data sheet

Product Details

Human, Sheep, Cow, Dog, Pig, Guinea pig, Rat, Mouse, Chicken
Antibody Type
Host Species
Ascites Fluid (contains 0.01M sodium azide).
The concentration is not quantified as this product is sold as undiluted crude mouse ascites fluid. The concentration might vary from lot-to-lot and an estimated concentration would be 1-3 mg/ml.
Storage & Handling
Store at -20°C. Upon initial thawing, apportion into working aliquots and store at -20°C. Avoid repeated freeze-thaw cycles to prevent denaturing the antibody. For long-term storage, keep the antibody at -80°C.

IF - Reported in the literature

Recommended Usage

Each lot of this antibody is quality control tested by immunohistochemical staining.

The extent of permissible dilution of SMI 22 beyond those recommended for general application depends upon nature and concentration of the antigen examined, species of the antigen, method of fixation and kind of section examined.
WB: 1:1,000
IHC: 1:1,000
ELISA: 1:1,000

Application Notes

This antibody is effective in immunoblotting (WB), immunocytochemistry, immunohistochemistry (IHC) and ELISA.

Monoclonal antibody cocktail against glial fibrillary acidic protein (GFAP) derived from the Bigner-Eng clones MAb1B4, MAb2E1 and MAb4A11

Each of the components of SMI 22 is specific for GFAP and visualizes immunocytochemically astrocytes and astrocytic processes as well as Bergman glia in a wide variety of species (human, sheep, cow, dog, pig, rat, guinea pig, rat, mouse and chicken). The mixture of the three antibodies provides, however, for a more comprehensive detection of astrocytomas than each antibody alone. Both, anaplastic and reactive astrocytes are stained immunocytochemically. Metastatic tumors and brain tumors of non-astrocytic origin, such as medulloblastomas, meningiomas, choroid plexus papillomas and schwannomas are not stained. There appears to be a positive correlation between fibrillarity of immunocytochemical localization in astrocytomas and their degrees of differentiation, and a negative correlation between the percentage of positive cells and the degree of anaplasticity. In morphologically diagnosed ependymomas and oligodendrogliomas positive reaction appears to reveal presence of malignant astrocytes.

Application References

(PubMed link indicates BioLegend citation)
  1. Vick WW, Bigner SH, Wikstrand CJ, Bullard DE, Kemshead J, Coakham HB, Schlom J, Johnston WW, Bigner DD: The use of a panel of monoclonal antibodies in the evaluation of cytologic specimens from the central nervous system. Acta. Cytol. 31:816, 1987.
  2. McLendon RE, Burger PC, Pegram CN, Eng LP, Bigner DD: The immunohistochemical application of three anti-GFAP monoclonal antibodies to formalin-fixed, paraffin-embedded, normal and neoplastic brain tissues. J. Neuropath. Exp. Neurol. 45:692, 1986.
  3. Pegram CN, Eng LF, Wikstrand CJ, McComb RD, Lee Y-L, Bigner DD: Monoclonal antibodies reactive with epitopes restricted to glial fibrillary acidic proteins of several species. Neurochem. Path. 8:119, 1985.
  4. Kanno H, et al. 2014. J. Neurosci. 5:1838. (IHC) PubMed
  5. Vergo S, et al. 2011. Brain 134:571. (IHC)
  6. Jiang H, et al. 2012. Neurology 17:1767. (IHC) PubMed
  7. Traka M, et al. 2008. J. Neurosci. 45:11537. (IHC) PubMed
  8. Bourque SL, et al. 2013. PLoS One 4:e61861. (IF) PubMed
  9. Chou VP, et al. 2014. J. Vis. Exp. 83:e50960. (WB)
Product Citations
  1. Traka M, et al. 2008. J Neurosci. 28:11537-11549. PubMed
  2. Jiang H, et al. 2012. Neurology. 79:1767-1773. PubMed
  3. Kanno H, et al. 2014. J Neurosci. 34:1838-1855. PubMed
  4. Bourque S, et al. 2013. PLoS One. 8:e61861. PubMed
  5. Yu K, et al. 2016. Nat Mater. 10.1038/nmat4624. PubMed
  6. Lin N, et al. 2016. Mol Biol Cell. 27(25):3980-3990. PubMed
  7. Polis B, et al. 2018. Neurotherapeutics. 15:1036. PubMed
  8. Care RA, et al. 2019. Cell Rep. 27:2171. PubMed
  9. Zelikoff JT, et al. 2018. Toxicol Sci. 162:276. PubMed
Publication Library
AB_2565344 (BioLegend Cat. No. 835301)

Antigen Details

Biology Area
Cell Biology, Neuroscience, Neuroscience Cell Markers
Molecular Family
Intermediate Filaments
Gene ID
2670 View all products for this Gene ID
View information about GFAP on


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Go To Top Version: 1    Revision Date: 03/27/2015

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