I linfociti del sangue di cordone ombelicale

Both acute and chronic Graft-versus-Host Disease (GvHD), a complication of allogeneic haematopoietic transplants, are described at a lower incidence and severity when human umbilical cord blood (HUCB) is used. Since mature T- cells play an important role in GvHD pathogenesis, we discussed the immunophenotypic and functional features of HUCB lymphocytes. Significant differences were found between HUCB and adult peripheral blood (PB) lymphocytes in their immunophenotypic profile. In particular, HUCB T-cells appear to be phenotypically immature. Indeed, as a likely consequence of poor antigenic experience during pregnancy, the majority of HUCB cells were naive, expressing the RA isoform of the CD45 molecule. In addition, in vitro activated CD4+ and CD8+ HUCB cells were analyzed for interferon-γ and interleukin-4 intracellular production, as expression of T(H)1 and T(H)2-like T-cell cytokine response, respectively. HUCB T lymphocytes were shown to be unable to perform both a T(H)1 and T(H)2-like response, as compared to normal adult PB cells. Taken together, the analyzed findings suggest that the immunophenotypic and functional immaturity of HUCB T cells was responsible for the clinical results in HUCB transplants.