Anti-ptf1a antibodies

Two rabbits (A and B) were immunized with a mix of two synthetic peptides of murine PTF1a sequence (one N-term peptide, KSFDNIENEPPFEFVS (aa 309-324) and one C-term peptide, EDFFTDQSSRDPLED (aa 24-38)) conjugated to keyhole limpet haemocyanin. C-term and N-term peptides have 100 % identity with rat sequence and 93% with human sequence.
We call our antibodies 7A (from rabbit A) and 7B (from rabbit B).
We designed Biacore experiments with immobilized peptides to test their specificity against immunogenic peptides (see Figure 1). 7A recognizes C-term sequence better than N-term sequence. 7B recognizes C-term sequence but not N-term sequence (see Figure 1).
Antibody 7B was purified against the « wrong peptide, N-term » but the flow through fraction has been kept. It has been tested and shows preserved immunoreactivity against C-terminal sequence (see Figure 1) and detects PTF1a in Western-Blot (see Figure 3).
We successfully used antibodies 7A and 7B in immunohistochemistry on human and mouse pancreas (see publication 1 and 3 and also see immunofluorescence in Figure 2), in immunocytochemistry of rat pancreatic acinar cells (see publication 1), Western-blot analysis of nuclear and cytoplasmic extracts of rat pancreatic acinar cells (see publication 1), of murine pancreatic acinar protein extracts (see publication 2), of transfected HEK cells (see publication 2), and in immunoprecipitation experiments (see publication 2).
Antibodies 7A and 7B are specific of pancreatic acinar cells and do not recognize any other proteins in Western-blot analysis of pancreatic ductal cells or COS cells (see Figure 3). Figure 3 also shows the absence of non specific bands.
We can provide around 30 ml of 7A antibody, 2 ml of unpurified 7B and 6 ml of 7B flow-through.
We also have lesser quantities of intermediate bleeds. Their specificity towards peptide antigens was also tested by Biacore, we can provide these results on demand in case of interest. We did not tested them in WB and IF/IHC.


Interest / Relevance: Pancreas transcription factor 1a (Ptf1a) is a basic helix-loop-helix (bHLH) transcription factor that plays important roles in the development of the central nervous system and the pancreas.

During embryogenesis PTF1a is expressed in multipotent pancreatic progenitors and is required for acquisition of pancreatic identity and determination of acinar cell fate.
PTF1a is also selectively expressed in the central and peripheral nervous system during embryogenesis: brain, cerebellum, retina, spinal cord, enteric nervous system. In these neural tissues PTF1 plays a key role in GABAergic neurons specification.
In adults, PTF1a has pancreas-specific expression (at protein level) and is exclusively present in exocrine acinar cells where it drives acinar cell-specific gene expression. PTF1a is a pancreatic acinar cell marker. We demonstrated that it is expressed in acinar-to-ductal metaplasia during pancreatitis and early steps of pancreatic cancer. It is lost in ductal pancreatic cancer. Immunodetection of PTF1a in adult pancreas may also detect facultative progenitors or plastic cells during tissue regeneration because PTF1a has reprogramming properties. Mutations in Ptf1a gene (coding and non-coding regions) result in pancreatic agenesis, diabetes mellitus, cerebellar agenesis.

With the exception of a single antibody (proposed for immunohistochemistry on frozen sections), none of the commercially available products display true specificity towards PTF1a. Indeed positive controls that are used for Western-blot or immunohistochemistry are inadequate (tissues or cells where PTF1a is not expresses such as liver, kidney, breast, ductal pancreatic cells etc…).
Moreover, PTF1a was previously called P48 because of its apparent molecular mass around 48kDa when migrating in electrophoresis. Once again, only another one commercially available antibody (proposed for Western-Blot) recognizes a protein migrating around 48kDa.
In contrast with commercially available products, our 7A and 7B anti-PTF1a antibodies are suitable for Elisa, Western-Blot (1 :500 – 1 :2000), immunoprecipitation (10 µl antibody), immunofluorescence/IHC (1 :500 – 1 : 2000) using frozen or paraffin sections and immunocytochemistry (1 :500-1
Keywords: pancreatic acinar cells, acinar-to ductal metaplasia, development, reprogramming, embryonic nervous system, plasticity
Scientist's name: Marlène BADTS - DUFRESNE
Véronique GIGOUX
Publications:
Publication 1: Id3 modulates cellular localization of bHLH Ptf1-p48 protein. Dufresne et al.
Int J Cancer 2011 Jul 15,129(2):295-306. doi: 10.1002/ijc.25668. Epub 2010 Nov 3
Publication 2: The E3 ubiquitin ligase thyroid hormone receptor-interacting protein 12 targets pancreas transcription factor 1a for proteasomal degradation. Hanoun et al.
J Biol Chem 2014 Dec 19,289(51):35593-604. doi: 10.1074/jbc.M114.620104. Epub 2014 Oct 29
Publication 3: The Loss of the E3 ubiquitin ligase TRIP12 inhibits Pancreatic Acinar Cell Plasticity and Tumor Cell Metastatic Capacity. Brunet et al.
bioRxiv 2023.03.08.531649, doi: https:/doi.org/10.1101/2023.03.08.531649

Reference:

RT00632

Business Developper
contact
Inserm Transfert
Research Tools
Source: Rabbit
Specificity: Mouse
Immunogen Seq ID: 2 peptides of mus musculus PTF1a (Q9QX98): KSFDNIENEPPFEFVS (aa 309-324) EDFFTDQSSRDPLED (aa 24-38)
Cellular Distribution: Nucleus, cytoplasm when delocalized in pathological conditions
Know Cross Reactivity: Human, rat
Rare disease: No
Last update: 11/09/2024

You might also be interested in