Anti-VEGF antibody [VG-1] (ab1316)

Does this antibody detect or cross react with the most abundant VEGF isoforms in rats (120, 164 and 188) ?

ANSWER:

Thank you for contacting us. To our knowledge, the epitope for the VG-1 clone has not been mapped. While we cannot say for certain which isoforms will be recognized in rat, bands are observed at ˜27 and 31 kDa in rat dermal epithelium samples. I hope this helps, please let me know if you need any additional information or assistance.

Dear madam,
Thank you for your reply. I've checked the protein ID: (http://www.uniprot.org/uniprot/P15692) , that you mentioned in your last mail. Thank you for your suggestion about the polyclonals, but I am mainly interested in the monoclonal.
I express my protein from this ORF :
http://www.ncbi.nlm.nih.gov/nuccore/190692100?report=fasta

This contains all the functional domains, same as the Swiss Prot sequence, but the swiss prot sequence has some amino acid extra at the C terminal, out of the functional domain regions.
My expressed protein sequence is :

xxx


I'll be grateful if you please have a look. I believe that the epitope (forab1316)is within myexpressed protein.

I can proceed to order, after receiving your valuable comment.

Thanking you,

Best Regards

ANSWER:

Thank you for your answer.

I have made now an alignment of the sequence you provided,with the three sequences we know the ab1316 does react with. Indeed the sequences are in identical in the the main parts. Please see here by yourself:
hhttp://www.ebi.ac.uk/Tools/services/web_clustalw2/toolresult.ebi?tool=clustalw2&jobId=clustalw2-I20120410-153045-0967-732581-pg

I can therefore confirm that the epitope is contained in your recombinantly expressed protein.
The antibody ab1316 will therefore most likely recognise your recombinantly expressed protein, if the expression is correct.

I hope this information is helpful. Please do not hesitate to contact us again should you have any concern or question.

Dear Madam/Sir,
I have a technical query about one of your product.
I am going to purchase one of your product :Anti-VEGF antibody [VG-1] (ab1316).
I express and purify recombinant VEGF from this clone:http://www.ncbi.nlm.nih.gov/nuccore/41351152?report=fasta
(Homo sapiens vascular endothelial growth factor A, mRNA (cDNA clone IMAGE:6006890), partial cds
GenBank: BC065522.1)

I am not sure that will your antibody detect my recombinant VEGF, mainly in Western Blot?
Please let me know ASAP.
Best regards

ANSWER:

Thank you for your inquiry.

We have not determined the exact epitope of the antibody ab1316. I can however confirm that this antibody does recognize the human121, 165 and 189 VEGF isoforms (SwissProt: P15692) and I would expect therefore that it would recognize also the recombinant VEGF you are expressing, if the recombinant VEGF from your source does not contain major modifications. The antibody is also guaranteed to work in Western blot.

In summary, I would expect the antibody to work on your protein, although we can not guarantee it.

As an alternative, you might can also look at a polyclonal antibody, which he has several epitopes, such as the ab14078, the ab17696or the ab9570.

http://www.abcam.com/index.html?datasheet=14078 (or use the following: http://www.abcam.com/index.html?datasheet=14078).
http://www.abcam.com/index.html?datasheet=17696 (or use the following: http://www.abcam.com/index.html?datasheet=17696).
http://www.abcam.com/index.html?datasheet=9570 (or use the following: http://www.abcam.com/index.html?datasheet=9570).

I hope this information is helpful. Please do not hesitate to let me know if you have any other questions or concerns.

Hi,

in response to your answer to my query below about detection of VEGF165b with anti-VEGF antibody ab1316,  I was wondering if it would be possible for abcam to test the cross-reactivity.  As of today, there are no known antibodies that have been tested that only react to VEGF165 but not its splice variant VEGF165b, and I feel this would be of enourmous benefit to the scientific community given the 'hot' status of VEGF165b and the importance of distinguishing between the two.  

Thank you, 

ANSWER:

Thank you for your suggestion. I will will put it forward as a suggestion but I think ab1316 would not be the best candidate as having performed sequence analysis of the isoforms this antibody has been shown to recognise (121, 165 and 189) with that of 165b, it seems unlikely that it would be specific for either 165 of 165b.

From the file I have attached, The sequence are as follows:

P15692-8 isoform 165b

P15692-9 isoform 121

P15692-11 isoform 165

P15692-13 isoform 189

From this it can be seen that the 6 amino acid residues of the C-terminal which differentiates between the 165 and 165b isoform are not present at all in isoform 121. I would therefore suspect that the antibody is not binding in this region.

I will however have a look through the rest of our catalogue to see if we have any other anti-VEGF antibodies which may be more likely to bind 165 specifically and put these forward for testing.

I will let you know of my progress. If you have any further questions or suggestion we would be very pleased to hear them.

Phone call enquiring as to whether ab1316 is able to recognise isoform 165b of VEGF

ANSWER:

Thank you for contacting us in regards to Anti-VEGF antibody [VG-1] (ab1316).

I’m afraid we currently have no information on whether this antibody would recognise the VEGF isoform 165b. The full length recombinant protein is used as the immunogen and in depth epitope mapping has as yet not been performed. However, as the only difference between the isoforms 165 and 165b is the final 6 C-terminal amino acids I think there is a good chance the antibody recognises a different region. I cannot guarantee it though.

We have two antibodies in our catalogue where the VEGF 165b is specifically recognised:

ab14994 is a mouse monoclonal which has been used to detect human and rat protein.

ab90719 is a rabbit polyclonal which has been used to detect human VEGF 165b.

Depending on the applications you intend to use one of these antibodies may be suitable for you. I hope this information has been of help. If you would like any further information please do let me know.