Overview

  • Product name
    Anti-Apolipoprotein E antibody
    See all Apolipoprotein E primary antibodies
  • Description
    Rabbit polyclonal to Apolipoprotein E
  • Host species
    Rabbit
  • Specificity
    Ab20874 is extremely low recognition of human Apo E. No data available regarding rat activity. We have data to indicate that this antibody may not cross react with Human. However, this has not been conclusively tested and expression levels may vary in certain cell lines/tissues.
  • Tested applications
    Suitable for: RID, Immunodiffusion, Immunoelectrophoresis, WB, IHC-Frmore details
  • Species reactivity
    Reacts with: Mouse, Rat
  • Immunogen

    Full length native protein (purified) corresponding to Mouse Apolipoprotein E.

Applications

Our Abpromise guarantee covers the use of ab20874 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
RID Use at an assay dependent concentration.
Immunodiffusion Use at an assay dependent concentration.
Immunoelectrophoresis Use at an assay dependent concentration.
WB 1/500 - 1/1000. Predicted molecular weight: 36 kDa. Dilution optimised using Chromogenic detection.
IHC-Fr Use at an assay dependent concentration. PubMed: 20505763

Target

  • Function
    Mediates the binding, internalization, and catabolism of lipoprotein particles. It can serve as a ligand for the LDL (apo B/E) receptor and for the specific apo-E receptor (chylomicron remnant) of hepatic tissues.
  • Tissue specificity
    Occurs in all lipoprotein fractions in plasma. It constitutes 10-20% of very low density lipoproteins (VLDL) and 1-2% of high density lipoproteins (HDL). APOE is produced in most organs. Significant quantities are produced in liver, brain, spleen, lung, adrenal, ovary, kidney and muscle.
  • Involvement in disease
    Defects in APOE are a cause of hyperlipoproteinemia type 3 (HLPP3) [MIM:107741]; also known as familial dysbetalipoproteinemia. Individuals with HLPP3 are clinically characterized by xanthomas, yellowish lipid deposits in the palmar crease, or less specific on tendons and on elbows. The disorder rarely manifests before the third decade in men. In women, it is usually expressed only after the menopause. The vast majority of the patients are homozygous for APOE*2 alleles. More severe cases of HLPP3 have also been observed in individuals heterozygous for rare APOE variants. The influence of APOE on lipid levels is often suggested to have major implications for the risk of coronary artery disease (CAD). Individuals carrying the common APOE*4 variant are at higher risk of CAD.
    Genetic variations in APOE are associated with Alzheimer disease type 2 (AD2) [MIM:104310]. It is a late-onset neurodegenerative disorder characterized by progressive dementia, loss of cognitive abilities, and deposition of fibrillar amyloid proteins as intraneuronal neurofibrillary tangles, extracellular amyloid plaques and vascular amyloid deposits. The major constituent of these plaques is the neurotoxic amyloid-beta-APP 40-42 peptide (s), derived proteolytically from the transmembrane precursor protein APP by sequential secretase processing. The cytotoxic C-terminal fragments (CTFs) and the caspase-cleaved products such as C31 derived from APP, are also implicated in neuronal death. Note=The APOE*4 allele is genetically associated with the common late onset familial and sporadic forms of Alzheimer disease. Risk for AD increased from 20% to 90% and mean age at onset decreased from 84 to 68 years with increasing number of APOE*4 alleles in 42 families with late onset AD. Thus APOE*4 gene dose is a major risk factor for late onset AD and, in these families, homozygosity for APOE*4 was virtually sufficient to cause AD by age 80. The mechanism by which APOE*4 participates in pathogenesis is not known.
    Defects in APOE are a cause of sea-blue histiocyte disease (SBHD) [MIM:269600]; also known as sea-blue histiocytosis. This disorder is characterized by splenomegaly, mild thrombocytopenia and, in the bone marrow, numerous histiocytes containing cytoplasmic granules which stain bright blue with the usual hematologic stains. The syndrome is the consequence of an inherited metabolic defect analogous to Gaucher disease and other sphingolipidoses.
    Defects in APOE are a cause of lipoprotein glomerulopathy (LPG) [MIM:611771]. LPG is an uncommon kidney disease characterized by proteinuria, progressive kidney failure, and distinctive lipoprotein thrombi in glomerular capillaries. It mainly affects people of Japanese and Chinese origin. The disorder has rarely been described in Caucasians.
  • Sequence similarities
    Belongs to the apolipoprotein A1/A4/E family.
  • Post-translational
    modifications
    Synthesized with the sialic acid attached by O-glycosidic linkage and is subsequently desialylated in plasma. O-glycosylated with core 1 or possibly core 8 glycans. Thr-307 is a minor glycosylation site compared to Ser-308.
    Glycated in plasma VLDL of normal subjects, and of hyperglycemic diabetic patients at a higher level (2-3 fold).
    Phosphorylation sites are present in the extracelllular medium.
  • Cellular localization
    Secreted.
  • Information by UniProt
  • Database links
  • Alternative names
    • AD2 antibody
    • Apo-E antibody
    • APOE antibody
    • APOE_HUMAN antibody
    • APOEA antibody
    • Apolipoprotein E antibody
    • Apolipoprotein E3 antibody
    • ApolipoproteinE antibody
    • Apoprotein antibody
    • LDLCQ5 antibody
    • LPG antibody
    see all

Images

  • Anti-Apolipoprotein E antibody (ab20874) + 20ug rat hippocampal lysate

    Secondary
    anti-rabit HRP-labeled secondary antibody

    Predicted band size: 36 kDa



    Rabbit polyclonal to Apolipoprotein E (ab20874) in western blot analysis of proteins isolated from 100mg of rat brain hippocampaus. Tissue was homogenized in a 5V of gentle lysis buffer (10mM HEPES, 1mM EGTA, 5mM MgCl2, 142,5mM KCl, 0,25% NP-40, with Roche complete Protease Inhibitor Cocktail Tablets) and centrifuged 20 mins/14000rpm/4oC. Supernatants reserved and protein concentrations were assigned by Bradford method. Proteins were resolved onto 10% SDS-PAGE and blotted on nitrocellulose membranes (Amersham- Hybond C). The membranes were incubated with anti-ApoE (ab20874 at 1/400) for 2h at rm temp in 0.05% TBST (150 mM NaCl, 50 mM Tris, pH 7.0, and 0.05% Tween 20) with 3% milk. Following incubation with the anti-rabbit HRP-labeled secondary antibody (1/10000 in 0.05% TBST, 1h rm temp), blots were developed using the enhanced chemiluminescent substrate (ECL, Amersham Bioscience).

  • ab20874 staining Apolipoprotein E in rat brain tissue by Immunohistochemistry (Frozen sections). After fixation in 4% PFA in PBS (pH 7.4), brains were cryoprotected in 30% sucrose in PBS at +4°C, frozen, and thereafter kept at -80°C until used. For the immunostaining, brains were cryosectioned in 30 µm slices, collected in PBS (pH 7.4), and processed in a free-floating system. Slices were first incubated in the blocking solution (BS) containing 2% bovine serum albumin, 2% goat serum, and 0.1% Triton X-100 in PBS (pH 7.4) for 1 hour at room temperature, and thereafter with the primary antibody for 24–48 hours at +4°C in BS at a 1/1000 dilution. After washing in PBS, slices were incubated with the biotin-conjugated secondary antibody (1/4000) in BS, rinsed with PBS, and incubated with the avidin-peroxidase conjugate in BS for 1 hour at room temperature. The staining was detected using 3,3-diaminobenzidinetetrahydrochloride as a chromogen.

References

This product has been referenced in:
  • Mukwaya A  et al. Time-dependent LXR/RXR pathway modulation characterizes capillary remodeling in inflammatory corneal neovascularization. Angiogenesis 21:395-413 (2018). IHC-P ; Rat . Read more (PubMed: 29445990) »
  • Dong Z  et al. Loss of LCAT activity in the golden Syrian hamster elicits pro-atherogenic dyslipidemia and enhanced atherosclerosis. Metabolism 83:245-255 (2018). WB . Read more (PubMed: 29526535) »
See all 19 Publications for this product

Customer reviews and Q&As

1-10 of 14 Abreviews or Q&A

Application
Western blot
Sample
Mouse Purified protein (Brain)
Gel Running Conditions
Reduced Denaturing (10% gel)
Loading amount
15 µg
Specification
Brain
Blocking step
Milk as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 2% · Temperature: RT°C

Abcam user community

Verified customer

Submitted Jul 06 2015

Question
Answer

I have investigated this and am sorry to confirm that the concentration is not determined for ab20874 Apolipoprotein E antibody . Titer by RID (Radioimmunodiffusion) is determined which is 1:40.

Unpurified antibodies such as this one sold as whole antiserum will not always have a concentration stated on the datasheet. Antibody concentration is usually determined by protein assay, and serum / ascites / tissue culture supernatant will contain a lot of other proteins, which means the antibody quantification would not be accurate.

I can confirm that for whole antiserum, concentration of antibody is known to very between 1 - 10 mg/ml.

I am sorry we are not able to provide an exact concentration on this occasion, but hope this information will be helpful to you. If you have any further questions, please do not hesitate to contact us.

Read More

Answer

Unfortunately, since Anti-Apolipoprotein E antibody (ab20874) is a Whole antiserum and has not been purified, we have not determined the concentration. We estimate that it will be between 1-10 mg/ml.

Here is the protocol we use in-house to measure concentration of our rabbit monolconals via ELISA:

- Coat plates with 50 ng of screening antigen in 1X coating buffer (0.035M NaHCO3, 0.015 Na2CO3, pH 9.6)
- Incubate at 37C for 1-2 hrs or O/N at 4C
- Wash with TBST (0.05% Tween 20)
- Block with 60 ul/well of 1% BST in TBS for 1hr RT or 4C O/N while shaking
- Tap out blocking solution from plates
- Add primary antibody (50 ul/well of hybridoma supernatant)
- Use 1:10,000 of corresponding rabbit antiserum as a positive control
- Incubate 1.5 hrs @ RT on shaker
- Wash with TBST
- Add secondary antibody 50 ul/well goat anti-rabbit IgG [H+L] – Alkaline Phosphatase labeled @ - 1:2,500 in 1% BSA/TBS
- Incubate 1 hr at RT on shaker
- Wash with TBST x2
- Add 50 ul/well of pNPP substrate
- Incubate 15 min at RT
- Stop with 50 ul/well 3N NaOH
- Read at 405 nm on plate reader

Read More

Answer

Thank you for your enquiry.

I can confirm that ab20874 antibody is sold as whole antiserum. Unpurified antibodies, such as those sold as whole antiserum, ascites or tissue culture supernatant will not have a concentration stated on the datasheet. Antibody concentration is usually determined by protein assay, and serum / ascites / tissue culture supernatant will contain a lot of other proteins, which means the antibody quantification would not be accurate.

I can confirm that for whole antiserum, concentration of antibody is known to very between 1 - 10 mg/ml.

I am sorry we are not able to provide an exact concentration on this occasion, but hope this information will be helpful to you. If you have any further questions, please do not hesitate to contact us.

Read More

Answer

Thank you for your reply.

I am sorry but xxxxx is currently out of the office but I will try to help with your enquiry.

We would normally advise using serum from the same species as the secondary antibody used is raise in. If your secondary antibody was raised in goat then using normal goat serum should be fine. If you were to use rabbit serum you would most likely end up with high background as your secondary antibody would detect any blocking serum binding the tissue sections.

We have quite a good practical guide to how to optimise IHC experiments which can be found from the following link:

https://docs.abcam.com/pdf/misc/abcam-protocols-book-2010.pdf

I hope this has been of help. If I can be of any further assistance, please do not hesitate to let me know.

Read More

Answer

Thank you for your enquiry and your interest.

Would you be so kind to clarify and confirm your question:

- in which application you wish to use the antibody,

- you wish to know the concentration of the recommended blocking agent OR

- the blocking time?

I look forward to hearing from you soon.

Read More

Answer

Thank you for contacting us.

I would be pleased to help you finding a suitable secondary antibody and a control for ab20874.

Could you please confirm what application you are going to perform and what conjugate is needed for the secondary antibody? This will help me to find the right products for your purpose.

I look forward hearing from you with the requested information.

Read More

Answer

Thank you for contacting us and your interest in our products.

Unfortunately, none of the three antibodies you are interested in have been tested in in both the application you are interested in with rat samples and we do not have any other antibodies against Apolipoprotein E which have either.

Ab7620 has been shown to detect the rat Apolipoprotein E, but has not been used in IHC. Ab1906 has been used in IHC with paraffin embedded sections but not with tissue from rat. From the sequence homology of the immunogen used I would also suggest that this anitbody would be unlikely to cross react with protein from rat. Finally, ab20874 has been used with rat samples and IHC with frozen sections, but not in paraffin embedded sections. We cannot therefore guarantee how any of these antibodies would perform in your experiment. I would suggest that ab23832 may be the most suitable to try to see if it would be suitable for your experiment.

We do however have an Abtrial program which may be of interest to you. This offer means that if you purchase ab23832 as normal, test the antibody with your rat samples in IHC-P and let us know of the results through an Abreview (no matter whether positive or negative) you would then be eligible to claim the value of ab23832 off any product in our catalogue. More information on this offer can be found here:

www.abcam.com/abtrial

Please note that the antibody to be tested must be purchased, tested, the Abreview submitted and the free product claimed within a 4 month period.

If you would be interested in participating in this scheme please do let me know as a discount code needs to be issued prior to the purchase of ab23832.

I hope this information has been of help. If I can be of any further assistance, please do not hesitate to let me know.

Read More

Question
Answer

Thank you for contacting us and for sending the questionnaire. The details provided enable us to closely monitor the quality of our products.

I am sorry this product did not perform as stated on the datasheet and for the inconvenience this has caused. The only lot of ab17929 we have in stock is the same as the one metioned in the questionaaire. Therefore, as requested, I have issued a free of charge replacement with one unit of ab20874. This free of charge replacement was added to the order number ******.

To check the status of the order please contact our Customer Service team and reference this number.

I looked at the protocol and I would like to suggest:
- to load a maximum of 30µg on the gel. Too much protein usually brings a lot of background.
- to dilute the primary antibody more (1/1000 is commonly used), too much antibody usually brings a lot of background too.

Please note that this free of charge replacement vial is also covered by our Abpromise guarantee. Should you still be experiencing difficulties, or if you have any further questions, please do not hesitate to let us know.

Read More

Question
Answer

I am sorry this product did not perform as stated on the datasheet and for the inconvenience this has caused. As requested, I have issued a free of charge replacement for one vial of ab20874.

To check the status of the order please contact our Customer Service team and reference this number.

Please note that this free of charge replacement vial is also covered by our Abpromise guarantee. Should you still be experiencing difficulties, or if you have any further questions, please do not hesitate to let us know.

I wish you the best of luck with your research.

Read More

1-10 of 14 Abreviews or Q&A

Please note: All products are "FOR RESEARCH USE ONLY AND ARE NOT INTENDED FOR DIAGNOSTIC OR THERAPEUTIC USE"

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