Key Specifications Table
|Species Reactivity||Key Applications||Host||Format||Antibody Type|
|M||ELISA, IP, WB, IH(P)||R||Purified||Monoclonal Antibody|
|Description||Anti-Laminin α1/β 1 Antibody, clone AL-4|
|Presentation||Purified from ascites by Protein G affinity chromatography. Purified immunoglobulin in 0.02M PB, 0.25M NaCl, pH=7.6, 0.1% sodium azide|
|Safety Information according to GHS|
|Storage and Shipping Information|
|Storage Conditions||Maintain between 2 and 8°C.|
|Material Size||100 µg|
References | 11 Available | See All References
|Reference overview||Application||Pub Med ID|
|Interaction between fibronectin and β1 integrin is essential for tooth development. |
Saito, K; Fukumoto, E; Yamada, A; Yuasa, K; Yoshizaki, K; Iwamoto, T; Saito, M; Nakamura, T; Fukumoto, S
PloS one 10 e0121667 2015
The dental epithelium and extracellular matrix interact to ensure that cell growth and differentiation lead to the formation of teeth of appropriate size and quality. To determine the role of fibronectin in differentiation of the dental epithelium and tooth formation, we analyzed its expression in developing incisors. Fibronectin mRNA was expressed during the presecretory stage in developing dental epithelium, decreased in the secretory and early maturation stages, and then reappeared during the late maturation stage. The binding of dental epithelial cells derived from postnatal day-1 molars to a fibronectin-coated dish was inhibited by the RGD but not RAD peptide, and by a β1 integrin-neutralizing antibody, suggesting that fibronectin-β1 integrin interactions contribute to dental epithelial-cell binding. Because fibronectin and β1 integrin are highly expressed in the dental mesenchyme, it is difficult to determine precisely how their interactions influence dental epithelial differentiation in vivo. Therefore, we analyzed β1 integrin conditional knockout mice (Intβ1lox-/lox-/K14-Cre) and found that they exhibited partial enamel hypoplasia, and delayed eruption of molars and differentiation of ameloblasts, but not of odontoblasts. Furthermore, a cyst-like structure was observed during late ameloblast maturation. Dental epithelial cells from knockout mice did not bind to fibronectin, and induction of ameloblastin expression in these cells by neurotrophic factor-4 was inhibited by treatment with RGD peptide or a fibronectin siRNA, suggesting that the epithelial interaction between fibronectin and β1 integrin is important for ameloblast differentiation and enamel formation.
|Short-lived recombinant adeno-associated virus transgene expression in dystrophic muscle is associated with oxidative damage to transgene mRNA. |
Dupont, JB; Tournaire, B; Georger, C; Marolleau, B; Jeanson-Leh, L; Ledevin, M; Lindenbaum, P; Lecomte, E; Cogné, B; Dubreil, L; Larcher, T; Gjata, B; Van Wittenberghe, L; Le Guiner, C; Penaud-Budloo, M; Snyder, RO; Moullier, P; Léger, A
Molecular therapy. Methods & clinical development 2 15010 2015
Preclinical gene therapy strategies using recombinant adeno-associated virus (AAV) vectors in animal models of Duchenne muscular dystrophy have shown dramatic phenotype improvements, but long-lasting efficacy remains questionable. It is believed that in dystrophic muscles, transgene persistence is hampered, notably by the progressive loss of therapeutic vector genomes resulting from muscle fibers degeneration. Intracellular metabolic perturbations resulting from dystrophin deficiency could also be additional factors impacting on rAAV genomes and transgene mRNA molecular fate. In this study, we showed that rAAV genome loss is not the only cause of reduced transgene mRNA level and we assessed the contribution of transcriptional and post-transcriptional factors. We ruled out the implication of transgene silencing by epigenetic mechanisms and demonstrated that rAAV inhibition occurred mostly at the post-transcriptional level. Since Duchenne muscular dystrophy (DMD) physiopathology involves an elevated oxidative stress, we hypothesized that in dystrophic muscles, transgene mRNA could be damaged by oxidative stress. In the mouse and dog dystrophic models, we found that rAAV-derived mRNA oxidation was increased. Interestingly, when a high expression level of a therapeutic transgene is achieved, oxidation is less pronounced. These findings provide new insights into rAAV transductions in dystrophic muscles, which ultimately may help in the design of more effective clinical trials.
|The extracellular matrix protein laminin α2 regulates the maturation and function of the blood-brain barrier. |
Menezes, MJ; McClenahan, FK; Leiton, CV; Aranmolate, A; Shan, X; Colognato, H
The Journal of neuroscience : the official journal of the Society for Neuroscience 34 15260-80 2014
Laminins are major constituents of the gliovascular basal lamina of the blood-brain barrier (BBB); however, the role of laminins in BBB development remains unclear. Here we report that Lama2(-/-) mice, lacking expression of the laminin α2 subunit of the laminin-211 heterotrimer expressed by astrocytes and pericytes, have a defective BBB in which systemically circulated tracer leaks into the brain parenchyma. The Lama2(-/-) vascular endothelium had significant abnormalities, including altered integrity and composition of the endothelial basal lamina, inappropriate expression of embryonic vascular endothelial protein MECA32, substantially reduced pericyte coverage, and tight junction abnormalities. Additionally, astrocytic endfeet were hypertrophic and lacked appropriately polarized aquaporin4 channels. Laminin-211 appears to mediate these effects at least in part by dystroglycan receptor interactions, as preventing dystroglycan expression in neural cells led to a similar set of BBB abnormalities and gliovascular disturbances, which additionally included perturbed vascular endothelial glucose transporter-1 localization. These findings provide insight into the cell and molecular changes that occur in congenital muscular dystrophies caused by Lama2 mutations or inappropriate dystroglycan post-translational modifications, which have accompanying brain abnormalities, including seizures. Our results indicate a novel role for laminin-dystroglycan interactions in the cooperative integration of astrocytes, endothelial cells, and pericytes in regulating the BBB.
|Cell delamination in the mesencephalic neural fold and its implication for the origin of ectomesenchyme. |
Lee, RT; Nagai, H; Nakaya, Y; Sheng, G; Trainor, PA; Weston, JA; Thiery, JP
Development (Cambridge, England) 140 4890-902 2013
The neural crest is a transient structure unique to vertebrate embryos that gives rise to multiple lineages along the rostrocaudal axis. In cranial regions, neural crest cells are thought to differentiate into chondrocytes, osteocytes, pericytes and stromal cells, which are collectively termed ectomesenchyme derivatives, as well as pigment and neuronal derivatives. There is still no consensus as to whether the neural crest can be classified as a homogenous multipotent population of cells. This unresolved controversy has important implications for the formation of ectomesenchyme and for confirmation of whether the neural fold is compartmentalized into distinct domains, each with a different repertoire of derivatives. Here we report in mouse and chicken that cells in the neural fold delaminate over an extended period from different regions of the cranial neural fold to give rise to cells with distinct fates. Importantly, cells that give rise to ectomesenchyme undergo epithelial-mesenchymal transition from a lateral neural fold domain that does not express definitive neural markers, such as Sox1 and N-cadherin. Additionally, the inference that cells originating from the cranial neural ectoderm have a common origin and cell fate with trunk neural crest cells prompted us to revisit the issue of what defines the neural crest and the origin of the ectomesenchyme.
|Monoclonal anti-mouse laminin antibodies: AL-1 reacts with laminin alpha1 chain, AL-2 with laminin beta1 chain, and AL-4 with the coiled-coil domain of laminin beta1 chain |
Schèele, Susanne, et al
Matrix Biol, 25:301-5 (2006) 2006
|Foxl2 disruption causes mouse ovarian failure by pervasive blockage of follicle development. |
Uda, M; Ottolenghi, C; Crisponi, L; Garcia, JE; Deiana, M; Kimber, W; Forabosco, A; Cao, A; Schlessinger, D; Pilia, G
Human molecular genetics 13 1171-81 2004
FOXL2 mutations cause gonadal dysgenesis or premature ovarian failure (POF) in women, as well as eyelid/forehead dysmorphology in both sexes (the 'blepharophimosis-ptosis-epicanthus inversus syndrome', BPES). Here we report that mice lacking Foxl2 recapitulate relevant features of human BPES: males and females are small and show distinctive craniofacial morphology with upper eyelids absent. Furthermore, in mice as in humans, sterility is confined to females. Features of Foxl2 null animals point toward a new mechanism of POF, with all major somatic cell lineages failing to develop around growing oocytes from the time of primordial follicle formation. Foxl2 disruption thus provides a model for histogenesis and reproductive competence of the ovary.
|Laminin-1 redistributes postsynaptic proteins and requires rapsyn, tyrosine phosphorylation, and Src and Fyn to stably cluster acetylcholine receptors. |
Marangi, PA; Wieland, ST; Fuhrer, C
The Journal of cell biology 157 883-95 2002
Clustering of acetylcholine receptors (AChRs) is a critical step in neuromuscular synaptogenesis, and is induced by agrin and laminin which are thought to act through different signaling mechanisms. We addressed whether laminin redistributes postsynaptic proteins and requires key elements of the agrin signaling pathway to cause AChR aggregation. In myotubes, laminin-1 rearranged dystroglycans and syntrophins into a laminin-like network, whereas inducing AChR-containing clusters of dystrobrevin, utrophin, and, to a marginal degree, MuSK. Laminin-1 also caused extensive coclustering of rapsyn and phosphotyrosine with AChRs, but none of these clusters were observed in rapsyn -/- myotubes. In parallel with clustering, laminin-1 induced tyrosine phosphorylation of AChR beta and delta subunits. Staurosporine and herbimycin, inhibitors of tyrosine kinases, prevented laminin-induced AChR phosphorylation and AChR and phosphotyrosine clustering, and caused rapid dispersal of clusters previously induced by laminin-1. Finally, laminin-1 caused normal aggregation of AChRs and phosphotyrosine in myotubes lacking both Src and Fyn kinases, but these clusters dispersed rapidly after laminin withdrawal. Thus, laminin-1 redistributes postsynaptic proteins and, like agrin, requires tyrosine kinases for AChR phosphorylation and clustering, and rapsyn for AChR cluster formation, whereas cluster stabilization depends on Src and Fyn. Therefore, the laminin and agrin signaling pathways overlap intracellularly, which may be important for neuromuscular synapse formation.
|Laminin expression in the mouse lung increases with development and stimulates spontaneous organotypic rearrangement of mixed lung cells. |
Schuger, L, et al.
Dev. Dyn., 195: 43-54 (1992) 1992
The recent establishment of a role for laminin in mouse lung organogenesis (Schuger et al. 1990a,b, 1991) prompted us to study its expression in the developing lung. Laminin A and B chains were detected in the murine lung from the first hours of development onward. In situ hybridization of mRNA as well as SDS-PAGE studies of lung cells in monoculture indicated that both epithelium and mesenchyme produce complete laminin molecules. Quantitative analysis of the in situ hybridization studies showed a gradual increase in laminin expression during development which was further supported by immunohistochemistry and ELISA. The overall pattern of expression suggested that the effects of laminin in morphogenesis were not restricted to a particular stage of development. Furthermore, the increase in expression during late development supported a role for the molecule in the fetal lung, which was not previously established. We next determined whether the increase in laminin production modulated the behavior of fetal lung cells as compared with their embryonic counterparts. We previously showed that organotypic pattern formation does not occur in cultures of mixed embryonic lung cells unless exogenous laminin is added (Schuger et al., 1990b). Organotypic pattern formation is the result of cell sorting into epithelial and mesenchymal compartments and further rearrangement in a pattern resembling the tissue of origin. In the present study, we demonstrated that organotypic pattern formation occurs spontaneously in cultures of mixed fetal lung cells, which express high laminin levels. Pattern formation was abolished by antibodies to laminin. These studies suggest a correlation between laminin expression and the ability of lung cells in culture to reproduce normal tissue patterns. We conclude that laminin is critical for epithelial-mesenchymal recognition and further morphogenic interaction during both the embryonic and fetal stages of lung development.
|Laminin on Toxoplasma gondii mediates parasite binding to the beta 1 integrin receptor alpha 6 beta 1 on human foreskin fibroblasts and Chinese hamster ovary cells. |
Furtado, G C, et al.
Infect. Immun., 60: 4925-31 (1992) 1992
We investigated the role of parasite-bound laminin and the host cell beta 1 integrin receptors for this extracellular matrix protein in Toxoplasma gondii binding to fibroblasts. Laminin but not fibronectin was detected on extracellular tachyzoites by immunofluorescence and immunoblotting. Binding of parasites to CHO cells was inhibited by polyclonal antibodies to laminin and by a monoclonal antibody directed against the globular carboxyl-terminal portion of the long arm of laminin (at or near the suggested ligand-binding sites for alpha 3 beta 1 and alpha 6 beta 1), but not by a monoclonal antibody directed against the lateral short arms of laminin near the cross region of the molecule. Antibodies to the alpha 6 but not the alpha 2, alpha 3, or alpha 5 chains of the beta 1 family of integrins blocked parasite attachment to human foreskin fibroblasts and CHO cells. Attachment of T. gondii to cells via laminin on the parasite surface and laminin receptors on the mammalian cell is consistent with the capacity of the parasite to invade almost all nucleated cells.
|Identification of laminin domains involved in branching morphogenesis: effects of anti-laminin monoclonal antibodies on mouse embryonic lung development. |
Schuger, L, et al.
Dev. Biol., 146: 531-41 (1991) 1991
We recently found that polyclonal antibodies to laminin, a basement membrane-related glycoprotein, inhibited murine lung morphogenesis when added to organ cultures of mouse embryonic lung. Using a series of monoclonal anti-laminin antibodies with previously characterized subunit specificity (termed AL-1, AL-2, AL-3, AL-4, and AL-5), the deposition and functional involvement of different laminin domains in the developing lung were investigated. By immunohistochemistry the antibodies' reactivity was largely localized to the basement membrane, but was also present diffusely in the extracellular matrix throughout the mesenchyme. Organ cultures of lung explants from Day 12 embryos were cultured for 3 days in the presence of 50-100 micrograms/ml of each antibody or in the presence of the same concentration of immunoglobulins G and M, laminin-neutralized antibody, or medium alone. Cultures were monitored by phase-contrast microscopy, light microscopy, and immunofluorescence. Although all antibodies penetrated the tissues in culture, only two of them inhibited branching activity. These two antibodies were AL-1, which binds on or near the cross region of laminin, and AL-5, which binds to the lateral short arms at the globular end regions of the B chain of laminin. Inhibition of branching with these two antibodies was dose-dependent and statistically significant for the two concentrations used. AL-2, AL-3, AL-4, laminin-neutralized antibodies and control immunoglobulins did not alter lung morphogenesis. The two domains of laminin that promote lung branching morphogenesis have been reported by others to promote the attachment of a variety of cells and/or bind heparin. These domains of laminin may promote branching morphogenesis by facilitating cell attachment and, consequently, cell proliferation.
|Localization of three distinct heparin-binding domains of laminin by monoclonal antibodies. |
Skubitz, A P, et al.
J. Biol. Chem., 263: 4861-8 (1988) 1988
Monoclonal antibodies were utilized to localize novel heparin-binding domains of laminin. A solid-phase radioligand binding assay was designed such that [3H] heparin bound to laminin in a time- and concentration-dependent manner. Tritiated heparin binding to laminin was saturable and specific as determined by competition with unlabeled heparin, dextran sulfate, and dermatan sulfate. By Scatchard analysis, two distinct dissociation constants were calculated (Kd = 50 and 130 nM), suggesting the presence of at least two binding sites for heparin on laminin. Tritiated heparin bound to thrombin-resistant (600 kDa) and chymotrypsin-resistant (440 kDa) laminin fragments, both known to lack the terminal globular domain of the long arm. Sodium dodecyl sulfate-polyacrylamide gels of chymotrypsin- and thermolysin-digested laminin chromatographed on a heparin-Sepharose column showed multiple proteolytic fragments binding to the column. Monoclonal antibodies generated against laminin were tested for their ability to inhibit [3H]heparin binding to laminin. Four monoclonal antibodies significantly inhibited the binding of [3H]heparin to laminin in the range of 15-21% inhibition. Laminin-monoclonal antibody interactions examined by electron microscopy showed that one antibody reacted at the terminal globular domain of the long arm, domain Hep-1, while epitopes for two of these monoclonal antibodies were located on the lateral arms of laminin, domain Hep-2, and the fourth monoclonal antibody bound below the cross-region of laminin, domain Hep-3. When two monoclonal antibodies recognizing distinctly different regions of laminin were added concomitantly, the inhibition of [3H]heparin binding to laminin increased almost 2-fold. These results suggest that at least two novel heparin-binding domains of laminin may be located in domains distinct from the terminal globular domain of the long arm.
|RAT ANTI-MOUSE LAMININ A CHAIN (PURIFIED) MONOCLONAL ANTIBODY|