A major obstacle in purifying either autologous or allogeneic hematopoietic stem cells from @entity1261 ( @entity1261 ) mobilized circulating progenitor cells (CPC) is represented by the huge cellularity present in each apheretic product. To obtain a significant debulking of unwanted cells from the leukapheresis, we developed a modified protocol of immune rosetting whereby @entity1 ABO-Rh- compatible red blood cells (RBCs) are treated with @entity33359 and then coated with murine monoclonal antibodies (MoAbs) against leukocyte antigens. When experiments were performed with leukaphereses obtained from normal donors or from @entity11511 ( @entity11511 ) @entity1 , RBCs were coated with @entity19 MoAbs against @entity1 mature myeloid cells ( @entity9536 ) and T cells ( @entity7279 ); whereas, in the case of @entity1 with B-precursor @entity981 , @entity1892 ( @entity1892 ), or @entity1582 ( @entity1582 ), RBCs were coated with anti- @entity9536 only. After incubation with CPC, rosetting cells (myeloid precursor cells, granulocytes, monocytes, and T cells) were removed by Ficoll-Hypaque density gradient centrifugation with a blood cell processor apparatus, COBE (Lakewood, CO) 2991. After this step, a significant reduction of the initial cellularity was consistently obtained (range, 72% to 97%), whereas the median absolute recovery of the @entity2280 + cells was above 85% (range, 64 to 100), with a 10-fold relative enrichment ranging from 3% to 41%. In a second step, CPC can be further purged of contaminating T or B cells by incubation with lymphoid-specific magnetic microbeads (anti- @entity3138 and - @entity4587 to remove T cells; anti- @entity1075 to remove B cells) and elution through a type-D depletion column (composed of ferromagnetic fiber) inserted within a SuperMACS separator device (Miltenyi Biotech, Bergisch-Gladbach, Germany). By this approach, a highly effective (three to four logs) T-cell depletion was achieved in all experiments performed with normal donors or @entity11511 @entity1 (median loss of CD3+ cells: 99.8% [range 99.2 to 100]) and an equally efficient B-cell depletion was obtained from B-precursor @entity981 , @entity1892 , or @entity1582 @entity1 . At the end of the procedure the T- or B-cell depleted fraction retained a high proportion of the initial hematopoietic @entity2280 + stem cells, with a median recovery above 70% (range 48% to 100%) and an unmodified clonogenic potential. In five @entity1 (two follicular NHL and three @entity981 ) the purified fraction of stem cells was found disease free at the molecular level as assessed by polymerase chain reaction (PCR) analysis of the t(14;18) chromosome translocation or clono-specific DNA sequences of @entity7513 or T-cell receptor gamma and delta chain genes. Purified autologous and allogeneic CPCs were transplanted in three and six @entity1 , respectively, who showed a prompt and sustained hematologic engraftment. In conclusion, this method represents a simple and reproducible two-step procedure to obtain a highly efficient purging of T or B cells from @entity1261 expanded and mobilized CPCs. This approach might lead to the eradication of the neoplastic clone in the autologous stem cell inoculum as well as for T-cell depletion during allogeneic transplantation.

Innovative two-step negative selection of XXXX -mobilized circulating progenitor cells: adequacy for autologous and allogeneic transplantation.

@entity1 :: ('9606', 'Species') :: ['human', 'patients'] @entity981 :: ('MESH:D054198', 'Disease') :: ['ALL'] @entity1261 :: ('1440', 'Gene') :: ['G-CSF', 'granulocyte colony-stimulating factor'] @entity7279 :: ('923', 'Gene') :: ['CD6'] @entity1075 :: ('930', 'Gene') :: ['CD19'] @entity19 :: ('10090', 'Species') :: ['murine'] @entity3138 :: ('914', 'Gene') :: ['CD2'] @entity4587 :: ('924', 'Gene') :: ['CD7'] @entity33359 :: ('MESH:C017133', 'Chemical') :: ['chromium chloride'] @entity1582 :: ('MESH:D009101', 'Disease') :: ['multiple myeloma', 'MM'] @entity1892 :: ('MESH:D016393', 'Disease') :: ['B-NHL', "B-cell non-Hodgkin's lymphoma"] @entity9536 :: ('3684', 'Gene') :: ['CD11b'] @entity2280 :: ('947', 'Gene') :: ['CD34'] @entity11511 :: ('MESH:D054218', 'Disease') :: ['T-ALL', 'T-cell acute lymphoblastic leukemia'] @entity7513 :: ('3492', 'Gene') :: ['IgH']
@entity1261 :: (1440,Gene) :: ['granulocyte colony-stimulating factor']
