Integration of morphological and immunophenotypic data is critical in achieving diagnosis accuracy and minimising interobserver interpretative discrepancies. The aim of this work was to compare the immunophenotype and the morphology of chronic lymphocytic leukaemia and mantle cell lymphoma, to help in the differential diagnosis of CD5 positive monoclonal B cells. Frozen/thawed samples from 91 patients were analysed retrospectively. Fresh samples from 17 mixed/atypical CLL and 13 MCL were tested to corroborate the results. Markers were analysed as percentage (%) of positive B lymphocyte subpopulation, and in terms of median fluorescence intensity (MFI). Matutes's CLL score clearly allowed distinguishing between classical CLL on the one hand, and atypical CLL and MCL on the other hand. The percentage of CD54-positive cells and the median fluorescence intensity of CD20 and CD54 were the only parameters which were significantly higher in MCL than in atypical CLL (P Ͻ 0.05), allowing an immunological distinction between these two entities. Nevertheless, due to a quenching problem when using CD20 and CD54 together, and because CD18 showed a statistically different expression between classical and atypical CLL, the combination of CD18/CD54 has been preferred and showed a different pattern in the three entities. Immunophenotyping could be helpful in the differential diagnosis of CD5-positive B cell chronic lymphoproliferative disorders with atypical features that do not fit exactly into any of the morphologic proposed groups. Leukemia (2001) 15, 1458-1465.

No abstract

No abstract

Summary:Cord blood (CB) transplantations are associated with low graft-versus-host disease (GVHD). The pathophysiology of GVHD involves interaction and activation of different cell types, as lymphocytes and monocytes, and results in a cascade of cytokine production. After antigen or mitogen stimulation, CB monocytes release lower levels of cytokines than adult blood (AB) monocytes. In this study, the detection of intracellular IL-1␤ and TNF-␣ produced by monocytes was evaluated in response to tuberculin PPD to investigate whether the reduced capacity of CB monocytes to secrete cytokines could be related to an impaired functional activity and to a particular phenotypic profile. Results showed that the percentage of CD64 + monocytes producing intracellular IL-1␤ and TNF-␣ was significantly lower in CB and that the phenotypic profile of CB monocytes producing these cytokine (CD64 + CD14 + ) was different to that of AB monocytes (CD64 + CD14 + , CD64 + CD33 + and CD64 + CD45RO + ). These results suggest that the lower capacity of CB monocyte populations to produce IL-1␤ and TNF-␣ might be due to a functional immaturity of CB monocytes at the cellular level as reflected by the different phenotypic profile of CB monocytes. Bone Marrow Transplantation (2001) 27, 1081-1086. Keywords: cord blood monocytes; intracellular cytokine; GVHD; bone marrow transplantation Clinical observations of umbilical CB transplantation show a reduced incidence of GVHD compared to allogeneic bone marrow transplantation (BMT). 1,2 GVHD is an immune reaction which results from a complex network of interactive cells producing or responding to a variety of cytokines and target structures. Its development involves activation of donor-derived T cells recognizing alloantigens presented by host-or donor-derived antigen presenting cells (APCs). However, the clinical manifestations result largely from cytokine dysregulation. 3,4 Comparison of the ability of CB and AB cells to produce cytokines has been analyzed by several groups and showed differences in their functional behavior. 5-9 Our previous study showed that after recombinant IFN-␥ stimulation, CB monocytes released lower levels of IL-1␤ and TNF-␣ than AB monocytes. 10 These cytokines have multiple immunological and inflammatory functions and are known to play a crucial role in the pathogenesis of GVHD. 11,12 Since cytokine production is an indication of cell function, the aim of this work was to determine intracellular production of cytokines in order to investigate whether the reduced capacity of CB monocytes to secrete IL-1␤ and TNF-␣ could be related to an impaired functional activity and to a particular phenotypic profile of CB monocytes. IL-1␤ and TNF-␣ production by PPD-stimulated cord and adult blood monocytes was assessed at the single cell level by flow cytometry. Materials and methods Collection of CB and AB samplesCord blood samples (n = 10) were obtained from normal full-term deliveries and collected through the umbilical vein, after delivery and before the expulsion of the placent...