Anti-Laminin α3B, Human, Mouse-Mono (Clone F7)

Anti-Laminin α3B, Human, Mouse-Mono (Clone F7)


General information 

Laminins, which consist of three subunits called α, β and γ chains, are major cell-adhesive components of extracellular matrix, especially basement membranes (BMs). The laminin family is constituted of over 15 isoforms, and each member is expressed in a tissue-specific manner and plays a differential role in each tissue. In the case of laminin α3 chain, there are two splicing variants, the truncated form α3A and the full-length α3B. Laminin-3A32 (Lm3A32) (Figure 1 left), formerly called laminin-5 or -5A, is composed of α3A, β3 and γ2 chains and distributed in the skin, esophagus, lung, breast and other epithelial tissues. This laminin has been extensively investigated in cancer biology because of its strong cell adhesion and cell motility activities. It also supports growth and adhesion of some types of stem cells. On the other hand, laminin-3B32 (Lm3B32) (formerly, laminin-5B; Figure 1 right) is composed of α3B, β3 and γ2 chains and less widely expressed than laminin-3A32. Although laminin-3B32 shows higher cell adhesion activity than laminin-3A32 in vitro, differences of biological functions between two laminins remain to be clarified. Recent studies identified laminin-3B11 (Lm3B11) as a new α3B-type laminin. Laminin-3B11 islocalized in vascular basement membranes in normal tissues, but this expression is down-regulated in cancer tissues. Laminin-3B11 stimulates microvascular endothelial cells to extend lamelliopodial protrusions. Dr. Kaoru Miyazaki and co-workers developed two types of anti-α3 antibodies, clone BG5 for α3A and clone F7 for α3B. Clone F7 is an only commercially available antibody for laminin α3B and can be applied for immunoblotting under both reducing and non-reducing conditions, immunohistochemistry, ELISA and immunoprecipitaiton/immunoaffinity purification. Clone F7 detects laminin-3B32 in the basement membranes of normal epithelial tissues and of relatively benign or differentiated carcinomas and laminin-3B11 in normal vascular basement membranes. Clone F7 is a powerful tool to detect laminin α3B isoform and investigate its fundamental functions in epithelial and vascular basement membranes. Note: anti-laminin α3A clone BG5 is also available as catalog no. FDV-0024.
 

Figure 1. Protein structure of laminin-332s and binding sites of antibodies

Western blot
Sample : recombinant human intact laminin-3B32 (Lm3B32) containing α3A, β3 and γ2 chains Gel conc. : Reduced conditions = 7% Non-reduced conditions = 5% 1 st Antibody : clone F7, 1/10,000 dilution 2 nd Antibody : anti-mouse IgG (H+L)-HRP conjugate
Validation of specificity by ELISA
Five recombinant human laminins were coated on multi-well plate and detected by clone BG5 and F7. BG5 detects Lm3A32 and Lm 3B32. F7 specifically detects Lm3B32 isoform.
Immunohistochemistry : Normal tissues
Sample: A Normal skin tissue (paraffin slice) B Normal esophagus tissue (paraffin slice) C Normal mammary gland (paraffin slice) D Normal lung tissue (paraffin slice) Black arrows: epithelial basement membranes Arrow heads : vascular basement membrane
Immunohistochemistry : Skin cancer tissue
Sample : Skin cancer tissue

1. Kariya et al., J. Biol. Chem., 279, 24774-24784 (2004) Characterization of laminin-5B (a3Bß3r2) and NH2- terminal proteolytic fragment of its a3B chain: Promotion of cellular adhesion, migration and proliferation.
2. Kariya et al., J. Mol. Histol., 39, 435-446 (2008) Localization of laminin alpha3B chain in vascular and epithelial basement membranes of normal human tissues and its down-regulation in skin cancers.
3. Mori et al., J. Biol. Chem., 285, 35068-35078 (2010) Laminin-3B11, a novel vascular type laminin capable of inducing prominent lamellipodial protrusions in microvascular endothelial cells.
4. Mori et al, Camcer Sci., 102, 1095-1100 (2011) Downregulation of a newly identified laminin, laminin-3B11, in vascular basement membranes of invasive human breast cancers.
5. Miyazaki et al., Cancer Sci., 107, 1909-1918 (2016) Highly sensitive detection of invasive lung cancer cells by novel antibody against amino-terminal domain of laminin gamma2 chain.

Aliases for LAMA3 Gene

• Laminin Subunit Alpha 3 ^2 3 5
• Laminin, Alpha 3 (Nicein (150kD), Kalinin (165kD), BM600 (150kD), Epilegrin) ^2 3
• Laminin Subunit Alpha-3 ^3 4
• Laminin-5 Subunit Alpha ^3 4
• Laminin-6 Subunit Alpha ^3 4
• Laminin-7 Subunit Alpha ^3 4
• Kalinin Subunit Alpha ^3 4
• Nicein Subunit Alpha ^3 4
• LAMNA ^3 4
• E170 ^3 4
• Laminin 5, Alpha-3 Subunit ³
• Epiligrin 170 Kda Subunit ³
• Epiligrin Alpha 3 Subunit ³
• Epiligrin 170 KDa Subunit ⁴
• Laminin-5 Alpha 3 Chain ³
• Epiligrin Subunit Alpha ⁴
• LAM3, Alpha-3 Subunit ³
• Kalinin 165kD Subunit ³
• Nicein 150kD Subunit ³
• BM600 150kD Subunit ³
• Laminin, Alpha 3 ²
• Kalinin-165kDa ²
• Nicein-150kDa ²
• BM600-150kDa ²
• Laminin A3 ³
• Epiligrin ²
• BM600 ³
• LAMA3 ⁵
• LOCS ³