GALECTIN-1 SENSITIZES RESTING HUMAN T LYMPHOCYTES TO FAS (CD95)-MEDIATED CELL DEATH VIA MITOCHONDRIAL HYPERPOLARIZATION, BUDDING AND FISSION

PAOLA MATARRESE,; ANTONELLA TIUNARI,; ELISABETTA MORMONE,; GERMÁN A. BIANCO,; MARTA A. TOSCANO,; BARBARA ASCIONE,; WALTER MALORNI*; GABRIEL RABINOVICH* (WM Y GAR COMPARTEN ÚLTIMA AUTORÍA)

JOURNAL OF BIOLOGICAL CHEMISTRY

American Society for Biochemistry and Molecular Biology

Lugar: Bethesda, MD; Año: 2005 vol. 280 p. 6969 - 6985

0021-9258

Galectins have emerged as a novel family of immunoregulatory proteins implicated in T-cell homeostasis. Recent studies showed that galectin-1 (Gal-1) plays a key role in tumor-immune escape by killing antitumor effector T cells. Here we found that Gal-1 sensitizes human resting T cells to Fas (CD95)/ caspase-8-mediated cell death. Furthermore, this protein triggers an apoptotic program involving increase of mitochondrial membrane potential and participation of the ceramide pathway. In addition, Gal-1 induces mitochondrial coalescence, budding and fission accompanied by an increase and/or redistribution of fission-associated molecules h-Fis and DRP-1. Importantly, these changes are detected in both resting and activated human T cells, suggesting that Gal-1-induced cell death might become an excellent model to analyze the morphogenetic changes of mitochondria during the execution of cell death. This is the first association among Gal-1, Fas/Fas L-mediated cell death and the mitochondrial pathway providing a rationale basis for the immunoregulatory properties of Gal-1 in experimental models of chronic inflammation and cancer.