Recombinant Human LAMB3 Protein: Properties & Applications

Recombinant Human LAMB3 Protein is a key extracellular matrix component derived from the laminin beta-3 subunit, essential for basement membrane assembly, epithelial cell adhesion, and the study of inherited blistering disorders such as junctional epidermolysis bullosa.

Protein Name

Recombinant Human LAMB3 (Laminin Subunit Beta-3)

SKU

rp366587

Protein Family

Laminin family, beta chain subgroup

Biological Role

Structural component of basement membranes; mediates cell adhesion, migration, and differentiation

Associated Disease

Junctional epidermolysis bullosa (JEB); mutations in LAMB3 are a leading cause of JEB

Expression System

Recombinant expression system (specific host system to be confirmed with product datasheet)

Research Applications

Cell adhesion assays, basement membrane reconstitution, disease modeling, Western blot, ELISA

What Is LAMB3 and Why Does It Matter?

LAMB3 encodes the beta-3 chain of laminin, a large heterotrimeric glycoprotein that forms a critical structural scaffold within basement membranes throughout the body. Laminins are composed of alpha, beta, and gamma chains assembled into a cross-shaped molecule; the beta-3 chain partners primarily with alpha-3 and gamma-2 chains to form laminin-332 (formerly known as laminin-5), one of the most biologically active laminin isoforms in epithelial tissues.

Laminin-332 is abundantly expressed at the dermal–epidermal junction, in the lung, kidney, and various mucosal surfaces, where it anchors epithelial cells to the underlying stroma via interactions with integrin receptors (notably α6β4 and α3β1) and other extracellular matrix proteins. This anchoring function is indispensable for tissue integrity, wound healing, and epithelial cell polarity.

Loss-of-function mutations in LAMB3 are among the most frequently identified genetic lesions in junctional epidermolysis bullosa (JEB), a severe and potentially life-threatening inherited blistering disorder. The absence or dysfunction of laminin-332 at the dermal–epidermal junction results in skin fragility, extensive blistering, and impaired wound healing. Research into LAMB3 therefore has direct translational relevance for rare disease biology, gene therapy development, and regenerative medicine.

Biochemical Properties of Recombinant Human LAMB3 Protein

Recombinant Human LAMB3 Protein (SKU: rp366587) is produced using recombinant protein expression technology to deliver a well-characterized, research-grade reagent suitable for a broad range of in vitro assays. Key biochemical considerations for working with this protein include:

• Subunit composition: LAMB3 represents the beta-3 subunit of laminin. In its native context, it assembles with LAMA3 and LAMC2 to form functional laminin-332 heterotrimers. The recombinant form allows researchers to study the individual subunit's interactions and properties in isolation.
• Glycosylation: Native LAMB3 is a glycoprotein; the glycosylation profile of the recombinant protein will depend on the expression host system employed. Researchers should consult the product datasheet for specific details on post-translational modifications.
• Molecular weight: The mature native LAMB3 chain has a high molecular weight; the recombinant protein's observed molecular weight on SDS-PAGE may differ from the calculated molecular weight due to glycosylation and other post-translational modifications. Refer to the product datasheet for confirmed values.
• Purity and formulation: Recombinant LAMB3 from Aladdin Scientific is manufactured to research-grade purity. The specific purity percentage, buffer composition, and storage conditions are detailed on the product datasheet (referenced as absea#PP-2169).

Users are strongly advised to review the current product datasheet prior to experimental use to confirm lot-specific activity, purity, and recommended storage conditions.

Research Applications of Recombinant Human LAMB3 Protein

Recombinant Human LAMB3 Protein supports a diverse range of experimental applications across cell biology, biochemistry, and translational research:

Cell Adhesion and Migration Assays

LAMB3 can be used as a substrate coating to study integrin-mediated cell adhesion and spreading, particularly for epithelial and keratinocyte cell lines. It is valuable for dissecting the roles of specific laminin subunits in cell–matrix interactions and for screening compounds that modulate these interactions.

Basement Membrane Reconstitution

Researchers can incorporate recombinant LAMB3 into in vitro basement membrane models to study its contribution to laminin-332 assembly and to the structural integrity of the extracellular matrix. Such models are relevant for wound healing research and tissue engineering applications.

Disease Modeling and Mechanistic Studies

Given the central role of LAMB3 mutations in junctional epidermolysis bullosa and its reported involvement in cancer invasion and metastasis, recombinant LAMB3 is a valuable tool for studying disease mechanisms, identifying binding partners, and evaluating potential therapeutic interventions including gene correction strategies.

Immunoassays and Protein Interaction Studies

Recombinant LAMB3 is suitable for use as a standard or capture antigen in ELISA, as a target in surface plasmon resonance (SPR) or bio-layer interferometry (BLI) binding studies, and as an antigen for antibody validation. It can also be used in co-immunoprecipitation and pull-down assays to identify novel protein–protein interactions.

Western Blot and Analytical Applications

The recombinant protein serves as a positive control for Western blot experiments and can be used to validate antibody specificity against LAMB3 across various experimental systems.

Handling, Storage, and Quality Considerations

To maintain the activity and integrity of Recombinant Human LAMB3 Protein, researchers should adhere to the following general best practices, while always deferring to the specific instructions provided in the product datasheet (absea#PP-2169):

• Storage: Recombinant proteins are generally stored at –20 °C or –80 °C upon receipt to prevent degradation. Avoid repeated freeze–thaw cycles, as these can reduce protein activity and promote aggregation. Aliquoting the protein upon first thaw is strongly recommended.
• Reconstitution: If supplied in lyophilized form, reconstitute using the buffer and volume specified in the datasheet. Allow the vial to equilibrate to room temperature before opening, and mix gently by pipetting rather than vortexing.
• Working concentrations: Optimal working concentrations will depend on the specific assay format. Pilot titration experiments are recommended to determine the ideal concentration for each application.
• Quality control: Each lot of Recombinant Human LAMB3 Protein is subject to quality control testing. Refer to the Certificate of Analysis (CoA) for lot-specific purity, activity, and endotoxin data.
• Handling precautions: Handle as a research reagent following standard laboratory safety protocols. The protein is not intended for human therapeutic or diagnostic use.

Frequently asked questions

What is the biological function of LAMB3?

LAMB3 encodes the beta-3 subunit of laminin, which assembles with alpha-3 and gamma-2 chains to form laminin-332, a major component of epithelial basement membranes. Laminin-332 mediates epithelial cell adhesion, migration, and differentiation primarily through interactions with α6β4 and α3β1 integrins. It is essential for skin integrity and is critically involved in wound healing.

What disease is associated with LAMB3 mutations?

Mutations in LAMB3 are a leading genetic cause of junctional epidermolysis bullosa (JEB), a rare and severe inherited skin disorder characterized by fragile skin, extensive blistering at the dermal–epidermal junction, and impaired wound healing. LAMB3 has also been reported to be dysregulated in certain cancers, where altered laminin-332 expression may influence tumor invasion and metastasis.

What assay formats is Recombinant Human LAMB3 Protein suitable for?

Recombinant Human LAMB3 Protein (SKU: rp366587) is suitable for a range of applications including cell adhesion assays, ELISA (as standard or capture antigen), Western blot positive controls, protein–protein interaction studies (SPR, BLI, co-IP), and in vitro basement membrane reconstitution models. Researchers should validate the protein's performance in their specific assay system and consult the datasheet for recommended conditions.

How should Recombinant Human LAMB3 Protein be stored to maintain stability?

The protein should be stored at –20 °C or –80 °C as specified in the product datasheet. Repeated freeze–thaw cycles should be avoided; aliquoting upon first thaw is strongly recommended. Always refer to the current Certificate of Analysis and product datasheet (absea#PP-2169) for lot-specific storage and handling instructions.

Is Recombinant Human LAMB3 Protein suitable for use as a positive control in Western blot experiments?

Yes, Recombinant Human LAMB3 Protein is suitable as a positive control in Western blot experiments to confirm antibody specificity and assay performance. The expected band size may differ from the theoretical molecular weight due to post-translational modifications such as glycosylation; the product datasheet should be consulted for confirmed molecular weight information.

References

1. Aumailley M, et al. A simplified laminin nomenclature. Matrix Biol. 2005;24(5):326–332. doi:10.1016/j.matbio.2005.05.006
2. Has C, Bauer JW, Bodemer C, et al. Consensus reclassification of inherited epidermolysis bullosa and other disorders with skin fragility. Br J Dermatol. 2020;183(4):614–627. doi:10.1111/bjd.18921
3. Nishiuchi R, et al. Ligand-binding specificities of laminin-binding integrins: a comprehensive survey of laminin–integrin interactions using recombinant alpha3beta1, alpha6beta1, alpha7beta1 and alpha6beta4 integrins. Matrix Biol. 2006;25(3):189–197. doi:10.1016/j.matbio.2005.12.001
4. Aladdin Scientific product datasheet: Recombinant Human LAMB3 Protein, absea#PP-2169. Aladdin Scientific, Shanghai.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.