A comparative study on the purification of the Amaranthus leucocarpus syn. hypocondriacus lectin.

Prep Biochem Biotechnol

Departamento de Bioquímica, Instituto Nacional de Enfermedades Respiratorias, Tlalpan DF, Mexico.

Published: August 1999

Amaranthus leucocarpus lectin is a homodimeric glycoprotein of 35 kDa per sub-unit, which interacts specifically with N-acetyl-galactosamine. In this work, we compared different glycoproteins that contain Galbeta1-3 GalNAcalpha1-3 Ser/Thr or GalNAcalpha1-3 Ser/Thr in their structure as ligands to purify the A. leucocarpus lectin. From the glycoproteins tested, fetuin was the most potent inhibitor of the hemagglutinating activity and the better ligand for lectin purification; however, the use of desialylated stroma from erythrocytes represented the cheapest method to purify this lectin. O-linked glycans released from the glycoproteins used as affinity matrix and those from different erythrocytes were less inhibitory than parental glycoproteins. The NH2-terminal of the lectin is blocked; moreover, this is the only example of a lectin isolated from this genus to be a glycoprotein. Analysis of the glycoprotein sequences with inhibitory activity for the lectin, showed a different pattern in the O-glycosylation, which confirms that A. leucocarpus lectin recognizes conformation and, probably, distances among O-linked glycans moieties.

Download full-text PDF

Source
http://dx.doi.org/10.1080/10826069908544925DOI Listing

Publication Analysis

Top Keywords

leucocarpus lectin
12
lectin
9
amaranthus leucocarpus
8
galnacalpha1-3 ser/thr
8
o-linked glycans
8
comparative study
4
study purification
4
purification amaranthus
4
leucocarpus
4
leucocarpus syn
4

Similar Publications

T lymphocyte activation begins with antigen/MHC recognition by the TCR/CD3 complex followed by a costimulatory signal provided by CD28. The search for novel costimulatory molecules has been extensive due to their potential use as immunotherapeutic targets. Although some molecules have been identified, they are unable to provide sustainable signaling to allow for proper T cell activation and proliferation.

View Article and Find Full Text PDF

Neuroinflammation induced by amyloid β25-35 modifies mucin-type O-glycosylation in the rat's hippocampus.

Neuropeptides

February 2018

Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510, Mexico. Electronic address:

Amyloid-β (Aβ) plays a relevant role in the neurodegenerative process of Alzheimer's disease (AD). The 25-35 peptide of amyloid-β (Aβ25-35) induces the inflammatory response in brain experimental models. Mucin-type O-glycosylation has been associated with inflammation of brain tissues in AD, thus in this work, we aimed at identifying changes in the glycosylation profile generated by the injection of Aβ25-35 into the CA1 of the hippocampus of rats, using histochemistry with lectins.

View Article and Find Full Text PDF

Differential Expression of O-Glycans in CD4(+) T Lymphocytes from Patients with Systemic Lupus Erythematosus.

Tohoku J Exp Med

September 2016

Unidad de Investigación Médica en Inmunología, Hospital de Pediatría, Centro Médico Nacional "Siglo XXI", Instituto Mexicano del Seguro Social (IMSS).

T cells from patients with systemic lupus erythematosus (SLE) show a decreased activation threshold and increased apoptosis. These processes seem to be regulated by glycosylated molecules on the T cell surface. Here, we determined through flow cytometry the expression of mucin-type O-glycans on T helper cells in peripheral blood mononuclear cells (PBMC) from 23 SLE patients and its relation with disease activity.

View Article and Find Full Text PDF

Amaranthus leucocarpus lectin recognizes a moesin-like O-glycoprotein and costimulates murine CD3-activated CD4(+) T cells.

Immun Inflamm Dis

September 2015

Departamento de Bioquimica, Facultad de Medicina Universidad Nacional Autónoma de México ; Departamento de Investigación en Bioquimica Instituto Nacional de Enfermedades Respiratorias "Ismael Cosio Villegas", México.

The Galβ1,3GalNAcα1,O-Ser/Thr specific lectin from Amaranthus leucocarpus (ALL) binds a ∼70 kDa glycoprotein on murine T cell surface. We show that in the absence of antigen presenting cells, murine CD4(+) T cells activated by an anti-CD3 antibody plus ALL enhanced cell proliferation similar to those cells activated via CD3/CD28 at 48 h of culture. Moreover, ALL induced the production of IL-4, IL-10, TNF-alpha, and TGF-beta in CD3-activated cells.

View Article and Find Full Text PDF

O-glycosylation of NnTreg lymphocytes recognized by the Amaranthus leucocarpus lectin.

Clin Dev Immunol

June 2014

Unidad de Investigación, Instituto de Oftalmología Fundación Conde de Valenciana, 06800 México, DF, Mexico ; Laboratorio de Inmunología, Departamento de Bioquímica, Facultad de Medicina, (UNAM), P.O. Box 70159, 04510 México, DF, Mexico.

O-glycosidically-linked glycans have been involved in development, maturation, homing, and immune regulation in T cells. Previous reports indicate that Amaranthus leucocarpus lectin (ALL), specific for glycans containing galactose-N-acetylgalactosamine and N-acetylgalactosamine, recognizes human naïve CD27(+)CD25(+)CD4(+) T cells. Our aim was to evaluate the phenotype of CD4(+) T cells recognized by ALL in peripheral blood mononuclear cells obtained from healthy volunteers.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!