These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Activated rat macrophages produce a galectin-1-like protein that induces apoptosis of T cells: biochemical and functional characterization.
    Author: Rabinovich GA, Iglesias MM, Modesti NM, Castagna LF, Wolfenstein-Todel C, Riera CM, Sotomayor CE.
    Journal: J Immunol; 1998 May 15; 160(10):4831-40. PubMed ID: 9590230.
    Abstract:
    Galectins, a family of closely related beta-galactoside-binding proteins, show specific immunomodulatory properties. We have recently identified the presence of a galectin-like protein in rat peritoneal macrophages by means of a cross-reactivity with a polyclonal Ab raised against a galectin purified from adult chicken liver. Galectin expression was up-regulated in inflammatory and activated macrophages, revealing a significant increase in phorbol ester- and formylmethionine oligopeptide-treated cells. In an attempt to further explore its functional significance, rat macrophage galectin was purified from activated macrophages by a single-step affinity chromatography on a lactosyl-Sepharose matrix. The eluted fraction was resolved as a single protein band of approximately 15,000 Da by SDS-PAGE that immunoreacted strongly with the anti-chicken galectin serum. Gel filtration studies revealed that the protein behaved like a dimer under native conditions, and saccharides bearing a beta-D-galactoside configuration were able to inhibit the hemagglutinating activity displayed by the purified galectin. In agreement with its isoelectric point of approximately 4.8, the amino acid analysis showed a definitive acidic pattern. Internal amino acid sequencing of selected peptides obtained by proteolytic cleavage revealed that this carbohydrate-binding protein shares all the absolutely preserved and critical residues found in other members of the mammalian galectin-1 subfamily. Finally, biochemical and ultrastructural evidence, obtained by genomic DNA fragmentation and transmission electron microscopy, are also provided to show its potential implications in the apoptotic program of T cells. This effect was quantified by using the terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end-labeling assay and was found to be associated to the specific carbohydrate-binding properties of galectin.
    [Abstract] [Full Text] [Related] [New Search]