I would like to sort antigen presenting cells that present the autoantigen MOG35-55 restricted by MHC class II (I-Ab). Does someone know if there are antibodies / tetramers that stain the complex of MHC class II with peptide (MOG 35-55) and which enterprise might produce this?
I don't know about commercial production, but these researchers screened a library for antibodies that recognized a HLA-MOG35 complex like what you describe. They may have isolated antibodies that would suit your pupose?
Eur J Immunol. 2011 May;41(5):1465-79. doi: 10.1002/eji.201041241. Epub 2011 Apr 12.
TCR-like antibodies distinguish conformational and functional differences in two- versus four-domain auto reactive MHC class II-peptide complexes.
Dahan R, Tabul M, Chou YK, Meza-Romero R, Andrew S, Ferro AJ, Burrows GG, Offner H, Vandenbark AA, Reiter Y.
Maybe you can try to generate this kind of APC by co-culture them in presence of the peptide MOG 35-55. You expand and purify them and later sort them by using specific markers for APC.
I don't have a specific answer, but I recently saw Brian Evavold speak about TCR specificity and MHC expressed on red blood cells (micropipette binding assay).
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0032562
Here they use tetramer specific for I-Ab MOG 38-49. Within the paper are references to work using pMHCII restricted to MOG 35-55. This is where they got some of their tetramers:
http://tetramer.yerkes.emory.edu/available/class2_premade
This group identified TCR-like antibodies from phage clones that recognized pMCH-II MOG complexes. Perhaps that may be a place to start.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3085348/
Unfortunately, I did not come across anything resembling your request. Most research is focused on the T cells, so there are plenty of ways to identify MOG specific TCR. I think the TCR-like Abs, when labeled with biotin, may be suitable for your needs. However, the TCR-MHC interaction is not always strong, and labeling this may prove difficult. T cells in vivo have the advantage of time, receptor localization and anchoring, and lipid domains to increase contact for activation.
Thanks for all the input... I know it's a tough question... perhaps labelling MOG fluorescently could work out? But I' don't think that the binding specificity could be retained
Well, if the likely antigenic regions of MOG are known, then could you attach Qdots to another region?
http://www.invitrogen.com/site/us/en/home/brands/Molecular-Probes/Key-Molecular-Probes-Products/Qdot/Frequently-Asked-Questions.html
Qdots are very small superconducting physical flourescent particles. There is some variety of protein-conjugating chemistry tools available for sticking them to various things, with variable specificity...haven't tried attaching them to a specific (unmodified) region of a target protein myself though.
You can't stain the MHC:Ag complex with tetramers--tetramers ARE Ag:MHC. In addition, it's possible that many cells are processing and presenting the peptide. It's possible someone has made an Ab against the MOG/MHC complex, since a transgenic mouse for it exists (So if the transgenic TCR can be inserted, then it can be made in an antibody or Fc-fusion Ig). GFP might be too weak to be detected. It might still work if MOG is tagged, because even if the peptide is processed, the GFP will be released into the APC as the MHC:Ag complex is loaded. This would indicate cells that have processed MOG at some point, but that's not the same as cells that have processed it for CLASS II presentation. I see someone has directed you to a paper about TCR-like antibodies, so maybe that's a good way to look for it. Good luck!!
- Badges
- Science topic
- Similar topics
- Medicine
- Disease
- Disease Models
- Animal Models
- Rodent Models
- Mouse Models