Th147 - The CD43 Sialomucin Promotes the Expression of GLUT-1 on the Membrane of T Cells

Erika Melchy-Perez, MSc – Academic Technician, Universidad Nacional Autónoma de México; Cristina Sotomayor-Vivas – Universidad Nacional Autónoma de México; Angel Flores-Alcantar, PhD – Academic Technician, Universidad Nacional Autónoma de México; Otoniel Rodriguez-Jorge, PhD – Investigator, Universidad Autónoma del Estado de Morelos; Yvonne Rosenstein, PhD – Principal investigator, Medicina Molecular y Bioprocesos, Instituto de Biotecnologia., Universidad Nacional Autónoma de México

Abstract Text: CD43 is a type I transmembrane sialomucin abundantly expressed in T cells. It has been implicated in thymocyte selection and maturation and the migration, adhesion, and activation of mature T cells. We hypothesized that its long and rigid structure positions CD43 as one of the initial molecules conveying environmental cues essential for complete T-cell activation. Specifically, we asked whether CD43-mediated signals participate in the metabolic adaptations that T cells undergo in response to activation signals, where aerobic glycolysis is essential. To this end, we evaluated the expression levels of the glucose transporter Glut-1 by flow cytometry, immunofluorescence, and qPCR in normal human peripheral blood CD4+ T cells, and Jurkat cells following activation with TCR/CD43, TCR/CD28, CD43, or CD28. In CD4+ T cells, GLUT-1 membrane expression increased ~10-fold in response to TCR/CD43 stimulation, surpassing that of TCR/CD28, while the single stimulation with CD43 or CD28 failed to increase the membrane GLUT-1 levels over basal values. Conversely, Jurkat cells exhibited an increase in both total and membrane GLUT-1 expression with the CD43 or CD28 single stimuli at 48h but not with the TCR/CD43 or TCR/CD28 stimuli. These results prompted us to explore whether CD43 expression correlates with Glut-1 expression in cancer. The GEPIA2 platform revealed 8 different types of cancer with CD43 overexpression and a positive correlation between CD43 and Glut-1 in acute myeloid leukemia. Our data uncovers a role for CD43-dependent signaling in promoting Glut-1 expression in both normal T lymphocytes and lymphoid tumor cells, expanding the functions of this molecule.