Two novel variants of uncertain significance in GP9 associated with Bernard-Soulier syndrome: Are they true mutations?

Bernard-Soulier syndrome (BSS) is an autosomal recessive major thrombocytopathy, the symptoms of which are mainly marked by mucocutaneous bleeding. This rare disease, initially described in the 1970s, is the result of an abnormal formation of the glycoprotein complex Ib-IX-V (GP Ib-IX-V), a platelet receptor of von Willebrand factor. A large number of mutations, sometimes involving the GP9 gene, have been described as possibly responsible for the disease. We report here the case of a BSS patient who presented with persistent thrombocytopenia (31x109/L) and decreased surface expression of GPIb-IX-V on large platelets with anisocytosis. Thorough molecular analyses disclosed two previously unreported GP9 variants, respectively c.230T>A (p.Leu77Gln) and c.255C>A (p.Asn85Lys). Both are likely to modify the conformation of GP-IX interactions with other glycoproteins of the Ib-IX-V complex and thus proper expression of this complex on the membrane of platelets.

High response rate and improved exercise capacity and quality of life with a new regimen of darbepoetin alfa with or without filgrastim in lower-risk myelodysplastic syndromes: a phase II study by the GFM.

Darbepoetin (DAR), with or without granulocyte colony-stimulating factor (G-CSF), has proved effective in treating anemia in patients with lower-risk myelodysplastic syndrome (MDS), but its effects on quality of life (QoL) and exercise functioning are less well established. In this phase II study (no. NCT00443339), lower-risk MDS patients with anemia and endogenous erythropoietin (EPO) level <500 IU/L received DAR 500 µg once every 2 weeks for 12 weeks, with G-CSF added at week 12 in non-responders. Physical performance was assessed with the 6-min walking test and, for fit patients, maximal oxygen consumption (VO2max). QoL was evaluated using SF-36 and FACT-An tests. In 99 patients, erythroid response rate according to IWG 2006 criteria was 48 and 56 % at 12 and 24 weeks, respectively. Addition of G-CSF rescued 22 % of non-responders. In 48 % of the responders, interval between darbepoetin injections could be increased for maintenance treatment. Serum EPO level was the only independent predictive factor of response at 12 weeks, and its most discriminant cutoff value was 100 IU/L. QoL and VO2max showed improvement over time in responders, compared with non-responders. With a median follow-up of 52 months, median response duration was not reached, and 3-year cumulative incidence of acute myeloid leukemia and overall survival (OS) was 14.5 and 70 %, respectively. Baseline transfusion dependence, International Prognostic Score System (IPSS), and Revised IPSS accurately predicted OS from treatment onset. Tolerance of darbepoetin was good. In conclusion, this regimen of darbepoetin every 2 weeks yielded high response rates and prolonged response duration. Objective improvement in exercise testing and in patient-reported QoL confirms the clinical relevance of anemia correction with erythropoiesis-stimulating agents.

Reduced levels of both circulating CD4+ CD25+ CD127(low/neg) and CD4+ CD8(neg) invariant natural killer regulatory T cells in stable heart transplant recipients.

A cross-regulation between two regulatory T cell (T(reg) ) subsets [CD4(+) CD25(+) and invariant natural killer (NK) T - iNK T] has been described to be important for allograft tolerance induction. However, few studies have evaluated these cellular subsets in stable recipients as correlates of favourable clinical outcome after heart transplantation. T(reg) and iNK T cell levels were assayed by flow cytometry in peripheral blood samples from 44 heart transplant recipients at a 2-year interval in 38 patients, and related to clinical outcome. Multi-parameter flow cytometry used CD4/CD25/CD127 labelling to best identify T(reg) , and a standard CD3/CD4/CD8/Vα24/Vß11 labelling strategy to appreciate the proportions of iNK T cells. Both subtypes of potentially tolerogenic cells were found to be decreased in stable heart transplant recipients, with similar or further decreased levels after 2 years. Interestingly, the patient who presented with several rejection-suggesting incidents over this period displayed a greater than twofold increase of both cell subsets. These results suggest that CD4(+) CD25(+) CD127(low/neg) T(reg) and iNK T cells could be involved in the local control of organ rejection, by modulating immune responses in situ, in clinically stable patients. The measurement of these cell subsets in peripheral blood could be useful for non-invasive monitoring of heart transplant recipients, especially in the growing context of tolerance-induction trials.

Alteration of the immunological synapse in lung cancer: a microenvironmental approach.

This study was designed to investigate the immunological properties of stroma reaction T cells and tumoral cells by comparison with non-tumoral lung tissue and local lymph nodes in order to explore interactions between tumour cells and the immune system. Immunodetection of major histocompatibility complex (MHC) molecules, CD3/T cell receptor (TCR) complex and T cell subsets markers was carried out in situ on frozen sections, and the semi-quantitative expression of CD3, CD4 and CD8 was examined in flow cytometry on lymphocytes of nodal, tumoral and healthy lung tissue from 62 patients with non-small cell lung cancer. This study showed alterations on lymphocytes and tumour cells in lung cancer, consistent with an impairment of T cell activation. CD3, TCR alpha beta and accessory molecules expression is down-modulated on peri- or intra-tumoral lymphocytes. MHC class I and class II molecules are down-modulated significantly on tumour cells. Other differences were noted, such as the reversed CD4/CD8 ratio of tumour infiltrating cells, compared to healthy lung tissues, consistent with the development of cytotoxic anti-tumoral responses. This study reports on the presence of a strong in vivo immunomodulating effect of tumour cells in human non-small cell lung cancer, likely to impair proper formation of the immunological synapse.

Immunoglobulin A nephropathy. Quantitative immunohistomorphometry of the tonsillar plasma cells evidences an inversion of the immunoglobulin A versus immunoglobulin G secreting cell balance.

Primary IgA nephropathy (Berger's disease) is characterized by renal deposits of IgA, the origin of which is still unknown. However, several clinical and biological findings suggest that these immunoglobulins might have a mucosal origin, and that such patients should present mucosal abnormalities. This paper reports the results of the immunohistomorphometrical analysis of tonsillar plasma cells from seven patients suffering from Berger's disease and seven controls also with recurrent tonsillitis. IgG, IgA, and IgM-secreting cells were enumerated after immunofluorescent staining of serial frozen-cut sections from 20 tonsils. In controls, a predominance of the IgG-secreting population, similar to this reported in the literature was observed (65% of IgG secreting cells and 29% of IgA plasma cells), while an inversion in the patients' plasma cells percentages was evidenced (IgG:37%, IgA:56%). This increment in the IgA population was paralleled by an augmentation of the number of dimeric IgA-secreting cells (75% of IgA plasma cells), stained both for cytoplasmic IgA and J chain. In controls, the latter cells were in similar proportions as previously reported by others (45% of IgA plasma cells). These results demonstrate an imbalance in the IgA-producing system of patients with Berger's disease, which is in keeping with the hypothesis favoring a mucosal origin for the mesangial IgA present in their kidneys.

2006 Bethesda International Consensus recommendations on the flow cytometric immunophenotypic analysis of hematolymphoid neoplasia: medical indications.

The clinical indications for diagnostic flow cytometry studies are an evolving consensus, as the knowledge of antigenic definition of hematolymphoid malignancies and the prognostic significance of antigen expression evolves. Additionally the standard of care is not routinely communicated to practicing clinicians and diagnostic services, especially as may relate to new technologies. Accordingly there is often uncertainty on the part of clinicians, payers of medical services, diagnostic physicians and scientists as to the appropriate use of diagnostic flow cytometry. In an attempt to communicate contemporary diagnostic utility of immunophenotypic flow cytometry in the diagnosis and follow-up of patients with hematolymphoid malignancies, the Clinical Cytometry Society organized a two day meeting of international experts in this area to reach a consensus as to this diagnostic tool. This report summarizes the appropriate use of diagnostic flow cytometry as determined by unanimous approval of these experienced practitioners.

Imatinib and methylprednisolone alternated with chemotherapy improve the outcome of elderly patients with Philadelphia-positive acute lymphoblastic leukemia: results of the GRAALL AFR09 study.

Acute lymphoblastic leukemia (ALL) in the elderly is characterized by its ominous prognosis. On the other hand, imatinib has demonstrated remarkable, although transient, activity in relapsed and refractory Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL), which prompted us to assess the use of imatinib in previously untreated elderly patients. ALL patients aged 55 years or older were given steroids during 1 week. Ph+ve cases were then offered a chemotherapy-based induction followed by a consolidation phase with imatinib and steroids during 2 months. Patients in complete response (CR) after consolidation were given 10 maintenance blocks of alternating chemotherapy, including two additional 2-month blocks of imatinib. Thirty patients were included in this study and are compared with 21 historical controls. Out of 29 assessable patients, 21 (72%, confidence interval (CI): 53-87%) were in CR after induction chemotherapy vs 6/21 (29%, CI: 11-52%) in controls (P=0.003). Five additional CRs were obtained after salvage with imatinib and four after salvage with additional chemotherapy in the control group. Overall survival (OS) is 66% at 1 year vs 43% in the control group (P=0.005). The 1-year relapse-free survival is 58 vs 11% (P=0.0003). The use of imatinib in elderly patients with Ph+ ALL is very likely to improve outcome, including OS.

Microfluidics in flow cytometry and related techniques.

Technological advances in laboratory automation are now well understood and applied as they considerably improved the speed and robustness of haematological laboratory data, in the companion fields of blood analyzers and flow cytometry. Still rather confidential is the field of microfluidics, mostly confined so far to academic settings and research laboratories. The literature in the field of microfluidics is growing and applications in hematology range from cell counting to flow cytometry, cell sorting, or ex vivo testing. A literature search allows to identify many innovative solutions developed to master the specific physics of fluid movements in microchips. Miniaturization also dwells on findings that have emerged from different areas such as electronics and nanoengineering. This review proposes an overview of the major principles guiding developments in microfluidics and describes a necessarily limited and nonexhaustive series of specific applications. Readers are strongly encouraged to consult the documents referred to in the references section to learn more about this world knocking at our door and possibly liable to revolutionize our profession of hematology biologists in a not so far future.

New parameters on the hematology analyzer XN-10 (SysmexTM) allow to distinguish childhood bacterial and viral infections.

INTRODUCTION: Complete blood counts (CBC) performed for infected children admitted for fever mostly disclose leukocytosis. Yet, the recently developed XN-10® provides novel CBC parameters which could be useful to ascertain infection and discriminate between bacterial and viral etiologies. These were the main objectives of the study presented here. METHODS: Blood samples from 90 children, 1 month to 5 years old, admitted to an emergency unit for fever benefited from a CBC, C-reactive protein, and procalcitonin assays. For 58, a bacterial infection was documented while a viral cause was disclosed for 32. Concomitantly, 30 healthy children of the same age range were selected as a control group. RESULTS: Complete blood counts parameters and leukocyte differentials allowed to statistically significantly disclose infection, compared to reference children, in the age group of 1-5 years old. Among the eight novel discriminant parameters, a particular interest appeared for Neutr-RI and Delta-He. They both were successfully incorporated in a score together with age and immature granulocytes (IG). ROC curves and AUCs were calibrated using a Hosmer-Lemeshow test. Moreover, novel lymphocyte parameters allowed to segregate bacterial and viral infections in the whole group of 90 febrile children. CONCLUSION: Complete blood counts is the most broadly performed rapid laboratory investigation. Here, we show that XN-10® provides complementary information allowing to confirm infection in febrile children, moreover discriminating between bacterial or viral origin.

Lymphocyte expansion after unrelated cord blood allogeneic stem cell transplantation in adults.

Limited information is available regarding the incidence and features of lymphocyte expansions after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Large granular lymphocytes (LGL) expansions have been reported after bone marrow or peripheral blood, but not after unrelated cord blood (UCB) allo-HSCT, associated with indolent clinical courses and favorable outcomes. Here, we considered 85 recipients of UCB allo-HSCT to more broadly define the impact of lymphocytosis, not limited to LGL. Sustained lymphocytosis was observed in 21 (25%) patients at a median onset of 12.6 months and with a median duration of 12 months. Immunophenotypic analysis showed predominantly CD8+ T and/or polyclonal B-cell expansions. Three patients only had monoclonal T-cell expansion. CMV reactivation was significantly more frequent in the group of patients with lymphocytosis (76% vs 28%, P=0.0001), but was not associated with survival. Conversely, 2-year disease-free survival and overall survival were significantly higher for lymphocytosis patients (85% vs 55%, P=0.01 and 85% vs 63%, P=0.03, respectively). In conclusion, expansion of T or B lymphocytes after UCB allo-HSCT in adults is not a rare event. Although occurring relatively late after transplant, this feature is predictive of a better outcome for the patients.

Flow cytometry in hematological nonmalignant disorders.

Multiparameter flow cytometry (MFC) has become an integral part of the diagnosis and classification of hematological malignancies. However, several nonmalignant or premalignant disorders may benefit from this technology in hematology laboratories. This review provides information on the normal immunophenotypic characteristics of peripheral blood leukocyte subsets and their modifications in several clinical conditions. The usefulness of MFC and the specific markers that can be investigated in hyperlymphocytosis, infection, hypereosinophilia, paroxysmal nocturnal hemoglobinuria, and large granular lymphocyte disorders is described. Mention is also made of the developments of MFC for analyses of red blood cells or platelets.

Impact of diet and nutraceutical supplementation on inflammation in elderly people. Results from the RISTOMED study, an open-label randomized control trial.

BACKGROUND & AIMS: Eating habits may influence the life span and the quality of ageing process by modulating inflammation. The RISTOMED project was developed to provide a personalized and balanced diet, enriched with or without nutraceutical compounds, to decrease and prevent inflammageing, oxidative stress and gut microbiota alteration in healthy elderly people. This paper focused on the effect on inflammation and metabolism markers after 56 days of RISTOMED diet alone or supplementation with three nutraceutical compounds. METHODS: A cohort of 125 healthy elderly subjects was recruited and randomized into 4 arms (Arm A, RISTOMED diet; Arm B, RISTOMED diet plus VSL#3 probiotic blend; Arm C, RISTOMED diet plus AISA d-Limonene; Arm D, RISTOMED diet plus Argan oil). Inflammatory and metabolism parameters as well as the ratio between Clostridium cluster IV and Bifidobacteria (CL/B) were collected before and after 56 days of dietary intervention, and their evolution compared among the arms. Moreover, participants were subdivided according to their baseline inflammatory parameters (erythrocytes sedimentation rate (ESR), C-Reactive Protein, fibrinogen, Tumor Necrosis Factor-alfa (TNF-α), and Interleukin 6) in two clusters with low or medium-high level of inflammation. The evolution of the measured parameters was then examined separately in each cluster. RESULTS: Overall, RISTOMED diet alone or with each nutraceutical supplementation significantly decreased ESR. RISTOMED diet supplemented with d-Limonene resulted in a decrease in fibrinogen, glucose, insulin levels and HOMA-IR. The most beneficial effects were observed in subjects with a medium-high inflammatory status who received RISTOMED diet with AISA d-Limonene supplementation. Moreover, RISTOMED diet associated with VSL#3 probiotic blend induced a decrease in the CL/B ratio. CONCLUSIONS: Overall, this study emphasizes the beneficial anti-inflammageing effect of RISTOMED diet supplemented with nutraceuticals to control the inflammatory status of elderly individuals.

Acute lymphoblastic leukemia relapsing after first-line pediatric-inspired therapy: a retrospective GRAALL study.

The outcome of adult patients with Philadelphia chromosome-negative acute lymphoblastic leukemia (Ph- ALL) relapsing after pediatric-inspired front-line therapy is ill known. Here 229 relapsing Ph- ALL younger adults (18-63 years) treated within the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003/-2005 trials were considered. Salvage regimens consisted of potentially curative therapies in 194 cases, low-intensity therapies in 21, allogeneic stem cell transplant (allo-SCT) in 6 and best supportive care in 8. Overall, 77 patients received allo-SCT after relapse. The median follow-up was 3.1 years. A second complete remission (CR2) was achieved in 121 patients (53%). In multivariate analysis, only younger age <45 years (P=0.008) and CR1 duration ⩾18 months (P=0.009) predicted CR2. Overall survival (OS) at 2 and 5 years was 19.3% (14-24%) and 13.3% (8-18%), respectively. In CR2 patients, disease-free survival (DFS) at 2 and 5 years was 29.0% (21-38%) and 25% (17-33%). In multivariate analysis, CR1 duration ⩾18 months and allo-SCT after relapse were associated with longer DFS (P<0.009 and P=0.004, respectively) and longer OS (P=0.004 and P<0.0001, respectively). In conclusion, although younger adults relapsing after pediatric-inspired ALL therapies retain a poor outcome, some of them may be cured if CR1 duration ⩾18 months and if allo-SCT can be performed in CR2. New therapies are definitely needed for these patients.

Isoelectric restriction of human immunoglobulin isotypes.

The partition of human serum immunoglobulins along a pH gradient of ampholynes was investigated using the recently developed method of preparative isoelectrofocusing. Each isotype was demonstrated to display a specific pI range, with limited overlapping. IgA appear to be the most acidic serum immunoglobulins while IgG are clearly basic.

Alternative rearrangements of immunoglobulin light chain genes in human leukemia.

Immunoglobulin heavy and light chain genes undergo rearrangement before they can be expressed by B-cells. A sequence of successive rearrangements has been proposed, suggesting that these events are initiated on heavy chain genes and are followed by sequential attempts of light chain gene rearrangements involving kappa gene alleles before lambda genes. This hypothesis, mainly established on B-cell clones of medullary origin, is consistent with the predominance of kappa chains among human serum immunoglobulins. However, data from tumors or normal lymphoid tissue suggest that lambda chain expression could be favored outside the bone marrow, due to an alternative rearrangement hierarchy. We investigated this hypothesis further on 17 leukemia samples. In three instances, we observed that lambda genes had undergone rearrangement while kappa genes remained in germline configuration. These data support the hypothesis of occasional alternative rearrangements of light chain genes.

Comparison of outcome, clinical, laboratory, and immunological features in 164 children and adults with T-ALL. The Groupe d'Etude Immunologique des Leucémies.

T cell acute lymphoblastic leukemia (T-ALL) is a disease of poor prognosis, usually studied separately in adults or children. Controversial clinical or biological prognostic factors have been reported, and little information is available regarding the frequency and prognostic value of membrane markers identified on blast cells. We report an extensive investigation of the incidence and prognostic value of immunophenotypic, clinical, and laboratory data in T-ALL, performed as a multicenter study in 164 patients. CD7, CD5, and CD2 were the most frequently expressed T cell antigens, and CD2 and CD4 were more frequently observed in children than in adults. MHC class II, CD9, and CD10 were observed in 16, 22, and 21% of the patients, respectively. The male prevalence of T-ALL, and the more frequent presence of a tumoral syndrome in children were confirmed, but mediastinal enlargement and high leukocyte counts were observed in less than half the patients. A poor prognosis was associated with the expression of MHC class II in adults. The presence of a mediastinal mass appeared to be of good prognosis in adults, as well as a leukocyte count lower than 100 x 10(9)/l whatever the age of the patient.

Immunological classification of acute myeloblastic leukemias: relevance to patient outcome.

Immunophenotyping is a major tool to assign acute leukemia blast cells to the myeloid lineage. However, because of the large heterogeneity of myeloid-related lineages, no clinically relevant immunological classification of acute myeloblastic leukemia (AML) has been devised so far. To attempt at formulating such a classification, we analyzed the pattern of expression of selected antigens, on blast cells collected at AML diagnosis. Patients were eligible if they had a first diagnosis of de novo AML and a sufficient number of blast cells for proper immunophenotyping. The relative expression of CD7, CD13, CD14, CD15, CD33, CD34, CD35, CD36, CD65, CD117, and HLA-DR were analyzed by cytometry in a test series of 176 consecutive AML cases. Statistical tools of clusterization allowed to remove antigens with overlapping distribution, leading us to propose an AML classification that was validated in a second AML cohort of 733 patients. We identified five AML subsets (MA to ME) based on the expression of seven antigens within four groups (CD13/CD33/CD117, CD7, CD35/CD36, CD15).-MA and MB-AML have exclusively myeloid features with seldom extramedullary disease and rare expression of lymphoid antigens. No cases of acute promyelocytic leukemia (APL) were observed within MB AML. MC AML have either myeloid or erythroblastic features. MD AML have more frequently high WBC counts than other subsets, which were related to the expression of CD35/CD36 and CD14 and to monoblastic differentiation. ME AML lack CD13, CD33, and CD117 but display signs of terminal myeloid differentiation. Specific independent prognostic factors were related to poor overall survival in each immunological subset: CD34+ (P<3 x 10(-4)) in MA AML, CD7+ in MB AML, non-APL cases (P<0.03) in MC AML, CD34+ (P<0.002) and CD14+ (P<0.03) in MD AML, CD14+ in ME AML (P<0.01). The inclusion of seven key markers in the immunophenotyping of AML allows a stratification into clinically relevant subsets with individual prognostic factors, which should be considered to define high-risk AML populations.

Proposals for the immunological classification of acute leukemias. European Group for the Immunological Characterization of Leukemias (EGIL).

Criteria for the immunological classification of acute leukemias are proposed by a recently established European group designated EGIL. The main aims of EGIL are to establish guidelines for the characterization of acute leukemias based on marker expression and provide a uniform basis for the diagnosis of the various types of these hemopoietic malignancies which should be helpful for future multinational clinical and laboratory investigations. Within the two major types (B and T cell lineage) of acute lymphoblastic leukemia (ALL), several groups are delineated according to the degree of cell differentiation. Within the acute myeloid leukemias (AML), only three subtypes as defined by the FAB classification: M0-AML, M6-AML and M7-AML, can be unequivocally defined by immunological markers; prospective studies are undertaken to see whether characteristic immunological profiles are associated with particular AML subtypes defined by specific cytogenetic abnormalities. Criteria for the definition of biphenotypic acute leukemia (BAL) are devised and a scoring system is outlined aimed to distinguish BAL from those acute leukemias with expression of a marker from another lineage. In addition, an uncommon subset of acute leukemias with no evidence of lymphoid or myeloid differentiation is recognized and the useful panel of markers to investigate and establish the cell nature of the acute leukemias is outlined. EGIL will focus in the future on testing the reproducibility of the proposed guidelines, particularly those for BAL, assessing their clinical value within a framework of multicentric trials and setting up uniform methodological criteria.

Surface markers in adult acute myeloblastic leukemia: correlation of CD19+, CD34+ and CD14+/DR--phenotypes with shorter survival. Groupe d'Etude Immunologique des Leucémies (GEIL).

The immunophenotype of blast cells was investigated in a multicentric study of 154 adult acute myeloblastic leukemias (AMLs). A panel of 27 monoclonal antibodies (MoAbs) was tested in indirect immunofluorescence. Expression of CD14 (UCHM1), CD19 (SB4), CD36 (OKM5), and HLA-DR were associated with higher mean leucocyte counts. CD14 expression correlated with low hemoglobin level and the absence of CD33 (MY9) with low platelet counts. Extramedullary disease was associated with CD16 (Leu11b) and HLA-DR antigen positivity. The study of relationships between surface markers and FAB criteria confirmed the predominant expression of CD14 in the M5 sub-group (p less than 0.000001) and the association of CD19 and CD36 with monocytic M4/M5 subgroups (respectively p less than 0.00002 and p less than 0.000001). All patients received an induction therapy including an anthracycline and cytarabine. The median follow-up was 13 months. The achievement of complete remission (CR) was inversely correlated with CD34 (B13C5) and CD19 expression: CR was obtained in 31 of 59 (53%) CD34-positive AML versus 64 of 75 (85%) CD34-negative cases (p less than 0.0001) and 11 of 24 (46%) CD19-positive versus 95 of 122 (78%) CD19-negative cases (p less than 0.01). In univariate analysis, a longer survival was associated with CD33 expression and the combined phenotypes CD36+/CD19- and CD16+/CD14-. Conversely, the CD18(IOT18)+/CDw65(VIM2)- phenotype was related to shorter survival. The expression of CD19, of CD34, and of the combined phenotype CD14+/DR--correlated with shorter survival as demonstrated both in univariate and multivariate analysis (p less than 0.03 in each case in multivariate analysis).