Anti-APC antibody [EP701Y] (ab40778)

Hi,
Could you help me by performing a BLASTp of the recognized epitope
(I know it is propietary) by your anti-APC [EP701Y] (ab40778) and the bovine APC
(uniprot Q1RMK3) and send me the results as % max ident, number of gaps, as well as a possible recommendation for using this antibody to detect the
cattle APC, please?

ANSWER:

The exact immunogen shares 100% identity with bovine APC, so the antibody is
predicted to cross-react with bovine protein, although we have not tested this reactivity yet.
I hope this is helpful. Please contact me again if you have any further questions.

we recently purchased your EMM43 APC monoclonal antibody (made in mouse) to reproduce our lates findings. We are soon ready to publish data using your antibodies, but we wonder if there is a chance of letting us know the peptide sequence of the immunizing peptide for this antibody (EMM43)? Since it is directed against the C-terminal of human APC, if the epitope lies within exon 15 it might not pick up the 160 kDa splice form discussed in previous mails (which your exon3-targeting EP701Y does!). This info is vital to our discussion, please let us know if you can assist us in this precious matter. If you cannot give us the sequence, is it perchance possible to give us information concerning which exon/s is/are targeted?

ANSWER:

Thank you for your enquiry.

The peptide sequence starts at AA 72: CLKELNLDSSNFPGVKLRSK. With this information, I hope you will be able to determine which exon it falls on.

Should you require any further assistance, please do not hesitate to contact me.

Good luck in your publication.

I believe what caused this e-mail exchange between us in the first place is your data sheet. First of all, your data sheets are usually flawless - with recommended dilutions, gel and IHC pictures and so forth which most companies exclude from theirs. However, this data sheet was a bit confusing regarding your WB image using the EP701Y antibody. We have managed to get three bands, two closely linked at 300 kDa, of which one is slightly bigger than the other in size, as well as the 160 kDa band. Your data sheet suggest that the "expected band size" of APC using this anitbody is 160 kDa. When I looked it up in the litterature, we figured that your antibody is targeting exon 3 of human APC, hence discovering NOT ONLY this unknown APC splice variant, but ALSO full length APC as well as isoform 2 (short) of 304 kDa. So I think you need to state this more clearly, since I was worried your antibody was ONLY detecting isoform 2 (short) which made no sense to me after reviewing the litterature. I can e-mail you the WB used with longer running time to separate the 300 kDa isoforms in higher resolution, but first after we have published the data. So, you have quite a precious antibody which detects all three forms of APC - and hence the loss of all three in tumor material would suggest certain inactivation patterns that is not possible using antibodies directing at other parts of APC, thus missing out on info regarding the 160 kDa variant - with unknown properties. I think it would be wise of you to state this, but that is merely the opinion of one young and fairly unexperienced researcher.Best regards, looking forward to more collaborations in the future,

ANSWER:

Thank you for your valuable feedback.

We will take into consideration the things you have mentioned and will keep other customers up to date as well.

We look forward to future collaborations with you and good luck in your research.

I disagree with removing the antibody from the stock, since it is directed at exon 3 and hence detects 160 kDa (alternative splicing) as well as full length APC (311) and isoform 2 (304 kDa) - I've confirmed these results with additional experiments! So your clone still is very valueable to us, and I do not want any refund! This is in agreement with several other companies providing this clone. The only thing that needs to be changed (according to my novice experience) is the data sheet which is somewhat confusing, regarding expected bands. You too have visible bands in the 300 kDa region. http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&cmd=search&term=APC%20160%20kDa (for more info. concerning why your ab detects 160 kDa)Best wishes and thaks for excellent service,

ANSWER:

Thank you for getting back to me.

I am glad to hear that you managed to obtain satisfactory results with this product.

I have checked the datasheets of other companies supplying this clone and it seems that our information are similar. Please forgive me for I do not know which part of our datasheet that is confusing? Is it the part that states the molecular weight to be 160kDa? Although this product is expected to detect the isoform 2 based on sequence analysis, but the actual band sizes that we obtain was around 160kDa and 250kDa. This 160kDa band is a spliced variant and we are not sure about the 250kDa band.

This product is one of our good sellers and we have not received any complaints. If there is any information that you think is misleading, I would certainly like to hear more about it from you.

If you should need anything else, please do not hesitate to contact me.

Have a nice day.