| First Author | Rabinovich GA | Year | 1998 |
| Journal | J Immunol | Volume | 160 |
| Issue | 10 | Pages | 4831-40 |
| PubMed ID | 9590230 | Mgi Jnum | J:47398 |
| Mgi Id | MGI:1203401 | Doi | 10.4049/jimmunol.160.10.4831 |
| Citation | Rabinovich GA, et al. (1998) Activated rat macrophages produce a galectin-1-like protein that induces apoptosis of T cells: biochemical and functional characterization. J Immunol 160(10):4831-40 |
| abstractText | 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 approximate-ly 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 approximate- ly 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. |
