BrdU (bromodeoxyuridine)

BrdU Antibodies

for Cell Proliferation Detection

Measurement of BrdU incorporation with anti-BrdU antibodies
 

Fig. 1. Chemical structures of thymidine and its analogs: BrdU, CldU, and IdU.

Fig. 1. Chemical structures of thymidine and its analogs: BrdU, CldU, and IdU. The structures are nearly identical apart from the fact that the methyl group (highlighted in blue) on carbon residue 5 of thymidine (PubChem CID: 5789) has been substituted by halogen molecules (Kolb et al. 1999). BrdU (PubChem CID: 6035): methyl group has been replaced with bromine (highlighted in green); CldU (PubChem CID: 65510): methyl group has been replaced with chlorine (shown in orange); IdU (PubChem CID: 5905): methyl group has been replaced with iodine (highlighted in magenta). Structures adapted from Iball et al. (1966) (BrdU), PubChem Compound Database (CldU and IdU), and Young et al. (1969) (thymidine).

The thymidine analog 5′-bromo-2′-deoxyuridine (BrdU) is a popular reagent in various scientific disciplines ranging from cancer to neuroscience research. The chemical is frequently added to samples, such as mammalian cell lines, and subsequently incorporated into newly synthesized DNA during replication. 

To measure cell proliferation, the incorporated BrdU is detected with anti-BrdU antibodies, such as the Mouse Anti-BrdU Antibody, clone Bu20a  (MCA2483). However, to ensure that the antibody is able to bind to BrdU, DNA treatment prior to antibody staining is required (Liboska et al. 2012). In the literature, endonucleases, such as DNase I (Deoxyribonuclease I) and acids, such as hydrochloric acid, are frequently used to cleave or denature the DNA to make incorporated BrdU accessible (Liboska et al. 2012).

Cross-reactivity of anti-BrdU antibodies
 

Although the chemical structures of thymidine and its analog BrdU are nearly identical, anti-BrdU antibodies, such as Mouse Anti-BrdU Antibody, clone Bu20a, have very little cross-reactivity to thymidine itself (Aten et al. 1992, Magaud et al. 1989). However many anti-BrdU antibodies, including clone Bu20a, recognize the other halogenated thymidine analogs 5′-chloro-2′-deoxyuridine (CldU) and  5′-iodo-2′-deoxyuridine (IdU) (Liboska et al. 2012, Kimoto et al. 2008). This is due to the structural similarities of the three different halogenated thymidine analogs, highlighted in Figure 1. Knowing the cross-reactivity of your anti-BrdU antibody is especially critical when performing double-labeling experiments with BrdU and other non-halogenated thymidine analogs, such as 5′-ethynyl-2′-deoxyuridine (EdU). 

Applications of the Mouse Anti-BrdU Antibody, clone Bu20a

Our Mouse Anti-BrdU Antibody, clone Bu20a, (MCA2483) has been tested in flow cytometry and immunocytochemistry. The product has been referenced in 12 publications. It is available in three different sizes (0.2 mg, 0.1 mg, and 20 µg) and conjugated to FITC (MCA2483FA). In addition to flow cytometry and immunocytochemistry, the Bu20a clone is recommended for immunohistochemistry.





 

BrdU image gallery


References

  • Aten JA et al. (1992). DNA double labeling with IdUrd and CldUrd for spatial and temporal analysis of cell proliferation and DNA replication. Histochemical Journal 24, 251-259. 
  • Iball J et al. (1966). Structures of 5-bromodeoxyuridine and 5-bromouridine. Nature 209, 1230-1232.
  • Kimoto M et al. (2008). Label-retaining cells in the rat submandibular gland. J Histochem Cytochem 56, 15-24.
  • Kolb B et al. (1999). Embryonic and postnatal injections of bromodeoxyuridine produce age-dependent morphological and behavioral abnormalities. J Neuro 19, 2337-2346.
  • Liboska R et al. (2012). Most anti-BrdU antibodies react with 2′-deoxy-5′-ethynyluridine – the method for the effective suppression of this cross-reactivity. PLoS One 7, e51679.
  • Magaud JP et al. (1989). Double immunocytochemical labeling of cell and tissue samples with monoclonal anti-bromodeoxyuridine. J Histochem Cytochem 37, 1517-1527.
  • National Center for Biotechnology Information. PubChem Compound Database; CID=5789
  • National Center for Biotechnology Information. PubChem Compound Database; CID=5905
  • National Center for Biotechnology Information. PubChem Compound Database; CID=6035
  • National Center for Biotechnology Information. PubChem Compound Database; CID=65510
  • Young DW et al. (1969). The crystal and molecular structure of thymidine. Aca Cryst B25, 1423-1432.