Osmotic gradient ektacytometry: A valuable screening test for hereditary spherocytosis and other red blood cell membrane disorders.

INTRODUCTION: New generation osmotic gradient ektacytometry has become a powerful procedure for measuring red blood cell deformability and therefore for the diagnosis of red blood cell membrane disorders. In this study, we aim to provide further support to the usefulness of osmotic gradient ektacytometry for the differential diagnosis of hereditary spherocytosis by measuring the optimal cutoff values of the parameters provided by this technique. METHODS: A total of 65 cases of hereditary spherocytosis, 7 hereditary elliptocytosis, 3 hereditary xerocytosis, and 171 normal controls were analyzed with osmotic gradient ektacytometry in addition to the routine red blood cell laboratory techniques. The most robust osmoscan parameters for hereditary spherocytosis diagnosis were determined using receiver operating characteristic curve analysis. RESULTS: The best diagnostic criteria for hereditary spherocytosis were the combination of decreased minimal elongation index up to 3% and increased minimal osmolality point up to 5.2% when compared to the mean of controls. Using this established criterion, osmotic gradient ektacytometry reported a sensitivity of 93.85% and a specificity of 98.38% for the diagnosis of hereditary spherocytosis. CONCLUSION: Osmotic gradient ektacytometry is an effective diagnostic test for hereditary spherocytosis and enables its differential diagnosis with other red blood cell membrane diseases based on specific pathology profiles.

Chronic non-spherocytic hemolytic anemia associated with severe neurological disease due to gamma-glutamylcysteine synthetase deficiency in a patient of Moroccan origin.

A previously undescribed mutation of hereditary gamma-glutamylcysteine synthetase (GCS) deficiency was found in a 5 year old boy of Moroccan origin. He presented with chronic haemolytic anaemia, delayed psychomotor development and progressive motor sensitive neuropathy of lower extremities. The parents were third degree relatives. The activity of glycolytic enzymes were found to be normal in the propositus, his parents and a sister, but and a complete lack of GSH was found in the propositus. Accordingly, the measurement of de novo GSH synthetic enzymes was undertaken, and severe GCS deficiency was found in the propositus. Both parents and his sister presented GCS activity ranging from 69% to 90% of normal. GCS gene sequencing showed that the propositus was homozygous for a 1241C>T mutation in exon 11 and both parents and his sister were heterozygous. This mutation predicts a Pro414Leu amino acid substitution. Even though the homology between GCS and crystallographically solved, functionally related proteins is not very high, a three-dimensional model of GCS was derived using Modeller Software. GCS deficiency is a very rare autosomal recessive disorder reported so far in only 8 unrelated probands with severe haemolytic anaemia. In only 3 of these was the anaemia associated with severe neurological dysfunction. We report here the fourth case of GCS deficiency presenting neuropathy, giving further support to the eventual relationship between this enzymopathy and neurological damage.

Control of phosphofructokinase by fructose 2,6-bisphosphate in B-lymphocytes and B-chronic lymphocytic leukemia cells.

The levels of fructose 2,6-bisphosphate and glucose 1,6-bisphosphate and the activities of the key glycolytic enzymes have been studied in T- and B-lymphocytes, and in B-chronic lymphocytic leukemia cells (B-CLL). In both kinds of cells these two bisphosphorylated metabolites have been identified and are present at similar concentrations. Their phosphofructokinase, like that of other normal or tumoral cells, is sensitive to these activators. Fructose 2,6-bisphosphate is the most potent stimulator; it displays the properties of a positive effector. It greatly increases the affinity for fructose 6-phosphate and relieves the inhibition by adenosine triphosphate, without changing Vmax. This effect is also synergistic with adenosine monophosphate. Despite few differences in the activity of phosphofructokinase and in the content of its main effectors in B-lymphocytes and in B-CLL cells, the kinetic properties of the enzyme from B-CLL cells were different, the enzyme being more sensitive to fructose 2,6-bisphosphate (Ka 2 orders of magnitude lower) and to glucose 1,6-bisphosphate than the enzyme from normal lymphocytes. The results reported showing that phosphofructokinase from B-CLL lymphocytes is altered in regulatory properties and the observed changes, in comparison to phosphofructokinase from normal B-lymphocytes, fit well with the hypothesis that fructose 2,6-bisphosphate can also assume a regulatory role in these cancer cells characterized by proliferation and accumulation of relatively mature-appearing lymphocytes.

Effect of TPA on fructose 2,6-bisphosphate levels and protein kinase C activity in B-chronic lymphocytic leukemia (B-CLL).

Normal B lymphocytes and peripheral mononuclear blood cells from B-chronic lymphocytic leukemia (B-CLL) patients were incubated in the presence of the tumor promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA). In normal B lymphocytes and lymphocytes from five patients with B-CLL, TPA stimulation increased lymphocyte fructose 2,6-bisphosphate (fructose 2,6-P2) content and activity of 6-phosphofructo 2-kinase (PFK-2), which is the enzyme that catalyzes the synthesis of fructose 2,6-P2. This effect was evident after 6 h and maximal after 12-24 h of TPA exposure. In three patients, lymphocytes seemed to be refractory to TPA stimulation in the conditions described here. Lymphocyte stimulation by TPA was associated with the translocation of protein kinase C (PKC) from the soluble to the particulate membrane fraction, except in B-CLL lymphocytes refractory to the TPA effect. These results give further support to the existence within B-CLL of subsets of cells which are refractory to the stimulation by TPA and demonstrate that the tumor promoter TPA induces important metabolic changes in lymphocytes of some patients with B-CLL.

Detection of circulating neoplastic cells by reverse-transcriptase polymerase chain reaction in malignant melanoma: association with clinical stage and prognosis.

PURPOSE: Circulating melanoma cells can be detected in peripheral blood by means of tyrosinase mRNA amplification by reverse-transcriptase polymerase chain reaction (RT-PCR). We conducted a prospective study to evaluate the clinical significance of the presence of circulating neoplastic cells in the blood of patients with malignant melanoma (MM). METHODS: A sensitive RT-PCR assay was used to detect tyrosinase mRNA in the peripheral blood of patients with stages I to IV melanoma. Healthy subjects or patients with other malignancies were used as negative controls. RESULTS: Ninety-one assessable patients were included in the study. There was a statistically significant association between RT-PCR positivity and clinical stage. Circulating melanoma cells were detected in 36% of patients with localized disease (stages I and II), in 45% of patients with regional nodal involvement (stage III), and in 94% of patients with metastatic disease (stage IV) (P < .001). In stage II-III patients who were RT-PCR-positive for mRNA tyrosinase in blood, the recurrence rate and disease-free survival were significantly worse than patients who were RT-PCR-negative. In multivariate analysis, RT-PCR was an independent prognostic factor for recurrence in patients with nonmetastatic disease (P = .002). CONCLUSION: The detection of circulating melanoma cells in peripheral blood by RT-PCR correlated with the clinical stage of patients with melanoma and was an independent prognostic factor for recurrence. Further studies are warranted to better assess the significance of this test in the evaluation of prognosis, early detection of relapse, and in monitoring the effectiveness of systemic therapy.

Phosphorylation of the MARCKS family of protein kinase C substrates in human B chronic lymphocytic leukemia cells.

Incubation of B chronic lymphocytic leukemia (B-CLL) cells with phorbol esters resulted in the phosphorylation of three Triton-soluble, heat-stable, acidic proteins with apparent M(r) of 80 KDa, 60 KDa and 43 KDa. The characteristics of the three proteins suggested that they could be related to the myristoylated, alanine-rich, C-kinase substrate (MARCKS). p80 was immunoprecipitated with an antibody against the N-terminal peptide of MARCKS. p43 co-migrated with mouse MRP/Mac-MARCKS (MARCKS-related protein). p60 is the most prominent substrate of protein kinase C in B-CLL cells.

Chronic myeloid leukemia of thrombocythemic onset: a CML subtype with distinct hematological and molecular features?

Among 84 consecutive patients with chronic phase Ph-positive chronic myeloid leukemia (CML) who were investigated for the hybrid BCR/ABL mRNA, in six cases (7%) the disease mimicked essential thrombocythemia (ET) at presentation, because of marked thrombocytosis (platelet counts ranging from 1003 x 10(9)/l to 2800 x 10(9)/l) and moderate leukocytosis (WBC counts from 10 x 10(9)/l to 19 x 10(9)/l). At initial examination, four of the six patients showed a few (4-9%) immature myeloid cells in the peripheral blood, and two had blood basophilia. All six patients later developed increasing leukocytosis, and two subsequently died from blast crisis and accelerated CML, respectively. In the overall series, 38 patients (45%) expressed the b2a2 type of BCR/ABL mRNA, and 46 (55%) either the b3a2 or both mRNAs. By contrast, only one of the six patients with CML of thrombocythemic onset expressed the b2a2 mRNA vs five with either b3a2 (n = 4) or both mRNA types (n = 1). The above results, in conjunction with similar data from a few previously published cases, suggest an association between the above form of CML and b3a2 type of BCR/ABL transcript.

Giant parallel tube arrays (PTAs), a new type of lymphocyte inclusion.

In a 56-year-old male patient, receiving chemotherapy after radical surgery for bladder carcinoma, an unusual type of cytoplasmic inclusion was discovered in about 30% of peripheral blood lymphocytes. This was a single, large (about 2 microns in diameter), round or ovoid body, darker than the nucleus and reddish-violet in May-Grünwald-Giemsa stain. The examination with transmission electron microscope demonstrated that such inclusions were made up of giant parallel tube arrays (PTAs). The absolute lymphocyte count was normal, but there was an expansion of CD3+, CD4-, CD8+, CD11b, TCR alpha beta lymphocytes. The lymphocytes bearing the inclusion were CD3+ and CD8+. DNA studies suggested an expansion of T-cell population with clonal rearrangement of TCR beta and TCR gamma. This case can be classified as an asymptomatic disorder of large granular lymphocytes, with unusual morphology. Giant PTAs should be taken into account in the differential diagnosis of lymphocyte cytoplasmic inclusions.

Sequential study of myeloid differentiation antigens of neutrophil granulocytes in different phases of chronic myeloid leukaemia: natural history and prognostic significance.

In an attempt to contribute to the knowledge of the natural history of Philadelphia-chromosome-positive chronic myeloid leukaemia (CML) and its prognosis, we analyzed sequentially the myeloid differentiation antigens of peripheral blood neutrophil granulocytes (NG) in different evolutive stages of the disease. Four monoclonal antibodies (CD15, CD24, 31D8, and 13F6) were used, and a total number of 116 sequential studies were performed in 43 patients. At diagnosis, there is a significant decrease of NG expressing myeloid differentiation antigens, which recover to nearly normal levels after initial control of the disease. The onset reduction is probably due to the circulation of incompletely mature NG. In accelerated/blastic phase NG expressing myeloid differentiation antigens decrease again, probably due to a true antigen loss. This reduction could herald by a few months the development of accelerated/blastic phase. In such a case, its predictive strength is higher than that of the well recognized initial prognostic parameters in CML. These results indicate that the sequential study of NG myeloid differentiation antigens may contribute to both a better understanding of the natural history of CML and the evolutive prognosis of this disease.

Recombinant alpha-2b-interferon may restore natural-killer activity in patients with B-chronic lymphocytic leukemia.

In nine patients with CLL treated with chlorambucil followed by alpha-2b-interferon (alpha 2b-IFN), T, B and natural killer (NK) cells and NK activity were studied before entering the study, after chlorambucil treatment, and after administration of alpha 2b-IFN. When considered as a whole, basal NK activity was lower in CLL patients than in controls (21.0% +/- 10.9 versus 40.2% +/- 17.4, p less than 0.001); however, when considered individually, four out of nine patients had normal NK activity at diagnosis. Chlorambucil did not increase global NK activity (21.7% +/- 7.1), whereas alpha 2b-IFN did so (44.3% +/- 19.1). After alpha 2b-IFN only one of seven patients studied had low NK activity. Previously increased absolute counts of CD2+, CD4+, CD8+, CD16+, CD57+ lymphocytes were reversed with chlorambucil treatment to normal levels, while after this therapy CD11b+ and CD19+ cells decreased without reaching normal values. During alpha 2b-IFN therapy, an increase up to normal levels in the percentage of CD16+ (2.7% +/- 3.4 versus 7.7% +/- 6.5, p = 0.04) and CD57+ (3.0% +/- 3.0 versus 8.1% +/- 6.2, p = 0.020) lymphocytes was observed whereas the absolute number of CD19+ B-cells further decreased (5.2 x 10(9)/l +/- 2.5 vs 3.8 x 10(9)/l +/- 2.3), albeit not significantly.

Immunophenotypic characteristics of blast crisis of chronic myeloid leukaemia: correlations with clinico-biological features and survival.

Blast cells from 40 patients with Philadelphia-positive chronic myeloid leukaemia (CML) in blast crisis were analysed by immunophenotypic methods. In 27 cases, BCR gene studies were also performed. By light microscopy morphology and cytochemistry the cases were classified as follows: undifferentiated (n = 7; 17.5%), myeloid (n = 27; 67.5%), and lymphoid (n = 6; 15%). On the basis of the immunological markers, the cases were reclassified as: myeloid (n = 17; 42.5%), megakaryoblastic (n = 17; 42.5%), and lymphoid (n = 6; 15%). The seven cases initially considered as undifferentiated by morphological and conventional cytochemical criteria were classified as myeloid (four cases) and megakaryoblastic (three cases) by marker analysis. The monoclonal antibody anti-myeloperoxidase (anti-MPO) was the most sensitive myeloid associated marker in these cases, being positive in five of them. A significant proportion (27%) of non-lymphoid blast crisis cases were CD7-positive, and myeloid markers were positive in the four lymphoid CML-CB cases studied. Analysis of the clinico-haematological characteristics on the various subgroups of patients showed that patients with lymphoid blast crisis had shorter duration of the chronic phase, more frequent extramedullary blastic involvement, more favourable response to therapy, and longer survival. Finally, a trend for an association between megakaryoblastic involvement of blast crisis and breakpoint localization in the 3' extreme of the M-bcr segment was also noted.

Ph-positive chronic myeloid leukemia mimicking essential thrombocythemia and terminating into megakaryoblastic blast crisis: report of two cases with molecular studies.

Two patients with chronic myeloid leukemia (CML) presenting with the hematologic features of essential thrombocythemia (ET) are reported. At diagnosis they showed extremely high platelet counts (4985 and 2800 x 10(9)/l, respectively) and moderate leukocytosis (21 and 17 x 10(9)/l, respectively). In both cases, in addition to the Philadelphia chromosome (Ph), a rearrangement within the major breakpoint cluster region on chromosome 22 was demonstrated, with the breakpoint in the 3' extreme. In patient 1 the disease initially responded to radioactive phosphorus and hydroxyurea, but during the evolutive course a progressive increase in the white blood cell counts was noted, reaching values typical of the chronic phase of CML, and the patient eventually died from blast crisis 45 months after diagnosis. In patient 2, although good control of the platelet counts was achieved with hydroxyurea, the disease also evolved into a blast crisis four months after diagnosis. In both cases monoclonal antibodies and electron microscopy studies demonstrated the megakaryocytic nature of the blast cells. The above features are not consistent with the present and similar cases being Ph-positive ET. Instead, they should be regarded as a special form of CML characterized by a marked protagonism of the megakaryocytic component.

Analysis of the clinical relevance of the breakpoint location within M-BCR and the type of chimeric mRNA in chronic myelogenous leukemia.

It has been suggested that the breakpoint location within the M-BCR segment of chromosome 22 and the type of chimeric mRNA BCR/ABL (b2a2 or b3a2) are associated with differences in the clinical and hematological characteristics of chronic myelogenous leukemia (CML). To assist in clarifying this matter, in a series of Ph-positive CML patients the relationship of both the breakpoint location within M-BCR (n = 71) and the type of chimeric mRNA BCR/ABL (n = 40) with the chronic phase duration, patients' survival, and thrombopoietic activity was analyzed. Median survival for patients with breakpoints in zones 1+2+3 (n = 38) and zones 4+5 (n = 31) was 62 and 75 months, respectively, the difference being not significant; patients with breaks in zones 1+2 (n = 19) and zones 3+4+5 (n = 50) had a median survival of 50 and 67 months, respectively (P also not significant). Moreover, no significant differences were found in the survival of patients with b2a2 (n = 16) and b3a2 (n = 24) mRNA junctions. Finally, no differences were observed in the platelet or megakaryocyte counts between patients with breakpoints in extremes 5' and 3' nor between patients with b2a2 and b3a2 mRNA. The above results are in agreement with those reported in most recent studies, confirming the lack of clinical relevance of molecular pattern in CML.

Presence of adenosine deaminase on the surface of mononuclear blood cells: immunochemical localization using light and electron microscopy.

Adenosine deaminase, which is essential for lymphoid differentiation and function, has previously been considered to be a cytosolic enzyme. In this report we demonstrate that it can be found associated with the plasma membrane of lymphocytes. By means of immunological techniques using both light and electron microscopy, adenosine deaminase was localized on the external side of the plasma membrane of normal lymphocytes and monocytes. Since the enzyme expression differed depending on the type of cell examined, new hypotheses about the mechanisms involving purine metabolism in immune dysfunctions or immunodeficiency syndromes may be considered.

Association of adenosine deaminase with erythrocyte and platelet plasma membrane: an immunological study using light and electron microscopy.

Adenosine deaminase has been localized in the plasma membrane of erythrocytes and platelets by means of immunological techniques using light and electron microscopy with cells in suspension. In erythrocytes, adenosine deaminase is associated with the external side of the plasma membrane. In platelets, the enzyme is associated with the external side of the plasma membrane, which is known to extend through the canalicular system of these cells. These results confirm our previous findings, based on biochemical studies, concerning the attachment of the enzyme to cell membranes.

Surface adenosine deaminase. A novel B-cell marker in chronic lymphocytic leukemia.

Previous studies found that ADA is present on the surface of mononuclear blood cells from healthy patients. Because the expression of this surface antigen depends upon the cell type, the presence of ADA on the plasma membrane of cells from patients with malignant hematologic diseases was studied by flow cytometry. The highest percentage of expression was found in CLL, whereas the lowest was found in T-cell-derived malignancies. The enzyme expression in immortalized cell lines showed a similar pattern, with the highest expression (95% +/- 5%) in the SKW64 B-derived cell line, the lowest (15% +/- 5%) in Jurkat T-lymphoma derived cells, and the intermediate (32% +/- 8%) in K562 cells derived from a chronic myelogenous leukemia. Double labeling ADA/CD5 and ADA/CD19, as well as the correlation of ADA expression with the expression of other surface markers, indicate that surface ADA might be considered a novel marker for CLL.

Evaluation of the Abbott Cell-DYN 3500 hematology analyzer in university hospital.

The Abbott (R) Cell-Dyn 3500 (Abbott CD 3500, Abbott Diagnostics Division, Mountain View, CA) is a fully automated hematology analyzer capable of providing a complete blood count (CBC) profile, including a five-part differential leukocyte count (DLC) and flagging system in this study. The CBC profile and DLC flagging system of the Abbott CD 3500 were evaluated according to the HA-20 protocol of the National Committee for Clinical and Laboratory Standards (NCCLS) and compared to the Technicon H*2 blood analyzer currently used in the authors' laboratory. Linearity, carryover, precision, and stability were all within the limits established by the manufacturer. No significant break-downs were found during the evaluation period. Evaluation of DLC indicated an excellent correlation with the manual reference method for neutrophils, lymphocytes, and eosinophils (r = 0.916, 0.936, 0.967, respectively), a good correlation for monocytes (r = 0.811) and a poor correlation for basophils (r = 0.224). Overall flagging for morphologic abnormalities displayed higher sensitivity (85%) than specificity (67%), with a false-positive ratio of 33%. In general, these results are in accordance with those obtained by other authors in the same period of time.

Early Pre-B Lymphoblastic Transformation in A Patient with Refractory Anemia.

A 77 year-old male with refractory anemia receiving only supportive therapy presented with an acute transformation six years following diagnosis. The lineage of the blast cells could not be ascertained by morphological and cytochemical studies. Nevertheless, immunophenotypical studies, including monoclonal antibodies against myeloid, monocytic, erythroid, megakaryo-cytic and T and B lymphoid antigens, and analysis of immunoglobulin and T-cell receptors genes demonstrated the early pre-B nature of the blasts. Lymphoblastic transformation is extremely rare in myelodysplastic syndromes (MDS). The case presented here and other similar cases previously reported are consistent with the concept that MDS are clonal disorders arising from a pluripotent stem cell.

Adult T-cell Leukemia in a Chilean Resident in Spain: Long-Lasting Remission after 2-Deoxycoformycin Treatment.

We report a patient born in a non-endemic area for human T-lymphotropic virus type I (HTLV-I) infection, in whom an adult T-cell leukemia (ATL) was diagnosed. After the development of acute symptomatic hypercalcemia, treatment with 2-deoxycoformycin was administered. Only mild side-effects were observed, and after treatment a long-lasting complete remission was achieved. The epidemiology of HTLV-I infection and the treatment of ATL are discussed.

Recommended procedures for the classification of acute leukaemias. International Council for Standardization in Haematology (ICSH).

The classification of acute leukaemias is now widely based on a combined morphological, cytochemical and immunophenotyping approach. Difficulties are frequently encountered however in reaching an acceptable degree of diagnostic concordance between different laboratories because of variations in the techniques used (in terms of methodologies, reagents and equipment) and diagnostic interpretation. The International Council for Standardization in Haematology (ICSH) convened an expert panel to consider currently available diagnostic techniques with the aim of defining a minimum cytochemical and immunological diagnostic panel that could be used as core components for the classification of acute leukemia. The proposed ICSH scheme, which attempts to balance the basic requirement for providing precise and informative diagnostic information without limiting its use to only those laboratories with sophisticated facilities, is based on three sequential levels of investigation; primary cytochemistry, intracellular phenotyping and membrane immunophenotyping. The minimum ICSH recommended cytochemistries comprise myeloperoxidase (MPO), chloroacetate esterase (ChlorE) and alpha-naphthyl acetate esterase (ANAE), and standardised methods for these cytochemistries are detailed in this communication. For cases of acute leukaemia that remain unclassified by primary cytochemistry, subsequent immunological analyses for cytoplasmic CD3, CD22, MPO and nuclear TdT are recommended. The ICSH panel considers that the use of these minimum primary cytochemical and intracellular phenotyping procedures will lead to the consistent classification of most acute leukaemias, and that the third level of investigation (membrane immunophenotyping) should be used for the purposes of confirmation, diagnostic clarification of atypical leukaemias, and the subtyping of acute lymphoblastic leukaemias (ALL). The ICSH panel also recognised that there are a number of additional technologies which can provide definitive diagnostic information, such as cytogenetics and DNA genotyping, but these were excluded from the minimum panel because of their restricted availability. While many specialised laboratories, particularly in the areas of diagnostic research, will continue to use individual investigatory protocols, it is considered that the inclusion of the ICSH scheme as core components would lead to greater consistency when comparing independent studies of acute leukemia.