Impaired T-cell activation and cytokine productivity after transplantation of positively selected CD34+ allogeneic hematopoietic stem cells.

Transplantation of positively selected, CD34(+) peripheral blood stem cells from alternative donors frequently results in delayed immune reconstitution. A shift towards a type 2 cytokine production might be a major contributing factor. We therefore decided to measure IFN-gamma, IL-2, IL-4, and IL-10 after stimulation of peripheral mononuclear cells with PMA/ionomycin and on a single cell level by intracellular cytokine staining during different stages of immune reconstitution.

Distinct contributions of CD4(+) and CD8(+) naive and memory T-cell subsets to overall T-cell-receptor repertoire complexity following transplantation of T-cell-depleted CD34-selected hematopoietic progenitor cells from unrelated donors.

Normalization of restricted T-cell-receptor (TCR) repertoire is critical following T-cell-depleted (TCD) stem cell transplantation. We present a prospective study analyzing respective contributions of naive and memory T-cell subsets within the CD4(+) and CD8(+) compartments to the evolution of overall TCR-repertoire complexity following transplantation of CD34-selected peripheral blood progenitor cells from unrelated donors. During the first year after transplantation, sorted CD4/45RA, CD4/45R0, CD8/45RA, and CD8/45R0 subsets were analyzed at 3-month intervals for TCR-repertoire complexity by CDR3 size spectratyping.