Human ApoE4 [Clone 4E4] Monoclonal Antibody— Purified No Carrier Protein

Synthetic peptide made to an internal region of human ApoE4

This purified antibody is sterile packaged and is formulated in 0.01 M phosphate buffered saline (150 mM NaCl) PBS pH 7.4 without adding sodium azide or BSA.

Liquid

Our Anti-Human ApoE4 [Clone 4E4] Monoclonal Antibody is produced under strict quality management systems to ensure maximum purity, activity, and lot-to-lot consistency.

- Production Facility: Proudly manufactured and purified at our state-of-the-art biotechnology facility in St. Louis, Missouri, USA.

- Quality Management: Processed and manufactured in accordance with ISO 9001:2015 certified quality standards.

- Environment: Cultured and purified inside dedicated Class 10,000 cleanroom suites to minimize external contaminants.

- Formulation: Prepared as a pure, liquid solution in sterile PBS with no carrier proteins or stabilizers, optimizing it for sensitive downstream immunoassays.

This purified antibody is stable when stored at 2-8°C. Do not freeze.

Research Use Only (RUO). Non-Therapeutic.

2-8°C Wet Ice

4E4 activity is specific to ApoE4, recognizing an internal domain present exclusively in the ApoE4 isoform.

Apolipoprotein E (ApoE) Isoforms and Structure

Apolipoprotein E (ApoE) is a major cholesterol-carrier glycoprotein essential for lipid metabolism and cholesterol transport in the central nervous system. In humans, ApoE exists as three major polymorphic isoforms—ApoE2, ApoE3, and ApoE4—which differ by single amino acid substitutions at residues 112 and 158:
- ApoE2: C112, C158
- ApoE3: C112, R158 (Most common isoform)
- ApoE4: R112, R158 [1]

Because these structural variations dictate functional differences, highly specific antibodies like Clone 4E4 are vital for distinguishing the ApoE4 isoform in complex biological samples.

The Role of ApoE4 in Alzheimer's Disease and Neurodegeneration

The ApoE4 allele is the strongest genetic risk factor for late-onset Alzheimer's Disease (AD), with carriers exhibiting significantly accelerated cognitive decline [2]. Research implicates the ApoE4 protein in multiple neurodegenerative pathways, including:

- Amyloid-β Pathology: Increased deposition and impaired clearance of amyloid-β plaques.

- Tau Phosphorylation: Promotion of neurofibrillary tangles and accelerated tauopathy.

Cellular Dysfunction: Disruption of mitochondrial function, altered lipid metabolism, and heightened neuroinflammation.

Broader Pathological Implications & Therapeutics

Beyond Alzheimer's Disease, ApoE4 expression is a recognized risk factor for vascular dementia, cerebral amyloid angiopathy, dementia with Lewy bodies, multiple sclerosis, and poor neurological outcomes following traumatic head injury. Conversely, ApoE4 has demonstrated a unique protective effect against age-related macular degeneration (AMD).

While ApoE4 carriers typically present with lower overall plasma and brain concentrations of ApoE, the precise relationship between protein concentration and its pathological activity remains a major focus of investigation. This has made the development of anti-ApoE4 therapies—designed to block pathological mechanisms and inhibit amyloid accumulation—a primary frontier in modern neuroscience and drug discovery.

ApoE is produced differentially in the central nervous system by astrocytes and microglia as well as peripherally by the liver and macrophages. ApoE does not cross the blood–brain barrier.

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2. Safieh M, Korczyn AD, Michaelson DM. BMC Med. 17(1):64. 2019.
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