Anti-C4 antibody [16D2] (ab11863)

Assuming you have not already tried this clone, 16D2, the antibody ab11863 should be capable of detecting mouse C4, but we do not know how much is expected to be present in brain tissue. We recommend a positive control of, for instance, mouse kidney. The following reference includes IHC data and a protocol for mouse kidney tissue that should be applicable to brain tissue. Please note though that the tissue that was stained for C4 was not PFA-perfused or formalin-fixed, just frozen and fixed on the slides with acetone.

Am J Pathol. Apr 2006; 168(4): 1241–1248.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1606553/

There are two other references listed on the datasheet that may be useful for mouse IHC. Here is a link:

https://www.abcam.com/c4-antibody-16d2-ab11863-references.html

Thank you for contacting us. I have been doing a little research into C4 and the antibodies that we currently have available against this target. As discussed on the phone, ab89537 recognises mouse C4d and C4 and has been tested in flow cytometry and ICC. We also have a rat monoclonal (ab11863), which is directed against mouse C4, and recognises C4b and C4d and has been used with flow cytometry and IHC-Fr. Unfortunately as human C4d only shares 82% homology with mouse C4d, the antibodies directed against human C4d are unlikely to react. From my understanding, C4 is cleaved into C4a and C4b by C1. C4b is then cleaved further to form C4c and C4d. An antibody which only recognises C4d (and not C4) is therefore unlikely to happen as the amino acid sequence of C4d is included in that of C4. Or did I misunderstand the question and were you asking for specificity against another isoform? I hope this information is helpful to you. Please do not hesitate to contact us if you need any more advice or information.

Thank you for contacting us. The following reference has used the antibody and gives details of its characterization: Murata, K et al; Synergistic deposition of C4d by complement-activating and non-activating antibodies in cardiac transplants. Am J Transplant 2007, 7: 2605 It may be necessary to activate the complement cascade to observe C4. It would suggest searching the literature for further information. We do have the human protein, but this antibody is directed against mouse so may not cross-react (ab98983-C4 protein). If you have further questions, please do not hesitate to contact us.