Identificación de células organizadoras de tejido linfoide en amígdalas humanas

Résumé

Secondary lymphoid organs (SLOs) originate during embryonic development through a close interaction between lymphoid tissue inducer cells (LTi cells) and lymphoid tissue organizers cells (LTo cells). This interaction results in the proliferation and maturation of both cell types, and the expansion of the SLO germinal primordium. Subsequently, B and T lymphocytes arrive to the primordium, the lymphoid microdomains are organized and LTo cells differentiate into Follicular Dendritic Cells (FDC), Marginal Reticular Cells (MRC) or Fibroblastic Reticular Cells (FRC), depending on the region of SLO. In this thesis, we obtain cell lines of tonsil stromal cells (TSC) and, for the first time in humans adult SLOs, we identified a cell population with a phenotype similar to murine LTo cells (Podoplanin+, CCL19+, CCL21+, CXCL13+, TRANCE+, ICAM-1+, VCAM-1+ and IL-7+), and, like LTo cells, they can also adhere and rescue from apoptosis to lymphoid cells. Moreover, these cell lines express mesenchymal stem cells (MSC) markers (CD10+, CD29+, CD44+, CD73+, CD271+, c-Kit+, Nestina+, NAGOG+, STRO-1+, and OCT-3/4+) and they can be differentiate into other mesenchymal lineage cell types.