In Vivo Star Anti-Human CD340 (HER2) Antibody

Cat # Size Price Quantity
5158011 mg$650
5158025 mg$1800
51580325 mg$5700

Product Details


Clone4D5-mg1
ApplicationDirect ELISA, functional assay, Flow Cytometry
Host SpeciesCHO cells
ReactivityHuman
FormatLiquid
Target NameHER2, HER-2, ERBB2, CD340, neu, MLN19, NEU, NGL, TKR1
Product DescriptionIn vivo Grade Recombinant Anti-Human HER2/ErbB-2/c-neu monoclonal Antibody
IsotypeMouse IgG1 Kappa
Antibody TypeRecombinant
Regulatory StatusRUO
Purity>95% by reducing SDS-PAGE
Endotoxin< 1 EU per 1 mg of the protein by the LAL method.
Storage Conditions4ºC
GradeIn vivo
Recommended UsageThis product is suitable in in vitro functional assays or in vivo on human cells used in animal models. Optimal amounts need to be determined empirically for each experiment.
Research AreasMesenchymal Stem Cells, Embryogenesis, Cancer Marker, Cancer Immunology
See All FormatsClone 4D5-mg1

Background Information


HER2 (Human Epidermal Growth Factor Receptor 2), also known as ERBB2 or CD340, is a transmembrane protein that plays a pivotal role in normal cell growth and differentiation. It is a member of the epidermal growth factor receptor (EGFR/ERBB) family of receptor tyrosine kinases. Under normal physiological conditions, HER2 is expressed at low levels on the surface of epithelial cells, where it helps regulate cell proliferation and survival signals. However, its primary fame in medicine comes from its potent ability to drive uncontrolled cell growth when the gene encoding it is amplified or the protein is overexpressed.

Structurally, HER2 consists of an extracellular ligand-binding domain, a transmembrane spanning region, and an intracellular tyrosine kinase domain. A unique and critical feature of HER2 is that it is an "orphan receptor," meaning it has no known direct ligand. Unlike other family members (EGFR, HER3, HER4) that require a growth factor to bind and activate them, HER2 exists in a constitutively open conformation, ready to interact. It functions by forming heterodimers with other ligand-bound members of the HER family. This makes HER2 the preferred dimerization partner for all other ERBB receptors, amplifying the signaling strength of the network significantly.

In the context of disease, HER2 is a major driver of tumorigenesis. Gene amplification leads to the overexpression of HER2 proteins on the cell surface, sometimes up to 100 times the normal level. This results in spontaneous dimerization and continuous, ligand-independent firing of growth signals, leading to aggressive cell division and resistance to apoptosis. HER2 overexpression is most notably observed in approximately 15-20% of breast cancers and a significant subset of gastric and gastroesophageal cancers, classifying them as "HER2-positive."

Therapeutically, HER2 is one of the most successful targets in the history of precision oncology. The development of trastuzumab (Herceptin), a monoclonal antibody that binds to the extracellular domain of HER2, revolutionized treatment by blocking downstream signaling and flagging cells for immune destruction. Therapy has since evolved to include dimerization inhibitors like pertuzumab, small-molecule tyrosine kinase inhibitors (TKIs) like lapatinib that work inside the cell, and antibody-drug conjugates (ADCs) like T-DM1 and trastuzumab deruxtecan. These ADCs use the HER2 antibody as a "Trojan horse" to deliver potent chemotherapy directly into the cancer cell, sparing healthy tissue.

Data Sheets


In Vivo Star Anti-Human CD340 (HER2) Antibody TDS

Related Protocols


Direct ELISA Protocol

Flow Cytometry Protocol

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Frequently Asked Questions


What are In Vivo Star Biofunctional Antibodies?
In Vivo Star antibodies are premium-grade monoclonal antibodies purified and formulated specifically for use in animal studies. Each lot is manufactured under stringent quality controls to ensure the low endotoxin levels, high purity, and functional activity required for reliable in vivo results.

How are these antibodies different from standard research antibodies (e.g., for Western blot or flow cytometry)?
Standard research antibodies are optimized for in vitro detection assays and may contain preservatives, carrier proteins (like BSA), or higher endotoxin levels unsuitable for injection. In Vivo Star antibodies are formulated in injectable-grade, azide-free, low-endotoxin buffers and validated for functional bioactivity in living systems rather than just antigen binding.

What endotoxin and purity specifications do these antibodies meet?
All In Vivo Star antibodies are tested and certified to meet low-endotoxin thresholds (typically <1 EU/mg, lot-dependent) using the LAL (Limulus Amebocyte Lysate) assay, and are purified to ≥95% purity by SEC-HPLC or SDS-PAGE. Exact specifications are provided on the Certificate of Analysis (CoA) for each lot.

Are these antibodies azide-free and carrier-free?
All In Vivo Star antibodies are formulated without sodium azide and without carrier proteins such as BSA or gelatin, since both can interfere with animal physiology or immune readouts during in vivo studies.

Do you provide isotype controls?
Matched isotype control antibodies (same host species, isotype, and formulation) are available upon request for most clones to support proper experimental controls.

How should In Vivo Star antibodies be stored and handled?
Store at 4°C for short-term use and avoid repeated freeze-thaw cycles, which can reduce bioactivity; aliquoting is recommended for long-term storage per the product-specific storage instructions on the Certificate of Analysis. Always confirm storage conditions and expiration on the CoA that accompanies each lot, as these can vary slightly by antibody.

Have a product or application question? Consult our FAQs or contact us.