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The first case of ribosome lamella complex (RLC) is reported in abnormal cells of a Sézary's syndrome, a T cell malignancy. Until now this ultrastructural cytoplasmic inclusion has usually been described in hairy cell leukaemia and other lymphoproliferative syndromes of B cell origin. Since RLC are also observed in abnormal lymphoid T cells, in non lymphoid cells, and moreover in non haematopoietic cells, they lack diagnostic specificity. [ABSTRACT FROM PUBLISHER]

Natural killer cells (NK) are pivotal cells of innate immunity. They are potent antileukemic cytotoxic effectors. A defect in their cytotoxicity has been described in some hematopoietic malignancies such as acute myeloid leukemia, multiple myeloma and myelodysplastic syndromes. This defect is at least partially linked to a decreased or absent expression of some activating NK cells molecules, more particularly the so-called natural cytotoxicity receptors. In the present study, we more particularly focused our attention on NK cells of polycythemia vera, a myeloproliferative disease characterized by the presence of mutated JAK2 tyrosine kinase. The polymerase chain reaction analysis of NK cells from patients showed that they expressed the mutated form of JAK2. In polycythemia vera the proportion of NK was increased compared to healthy donors. The proliferative and cytotoxic abilities of NK cells from patients were similar to healthy donors. Expression of activating or inhibitory receptors was comparable in patients and donors, with nonetheless an imbalance for the inhibitory form of the CD158a,h couple of receptors in patients. Finally, the transcriptomic profile analysis clearly identified a discriminant signature between NK cells from patients and donors that could putatively be the consequence of abnormal continuous activation of mutated JAK2., (Copyright © 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Polycythemia vera (PV) is a disease with slow development. Nonetheless, the immune response is unable to eliminate the uncontrolled proliferating hematopoietic cells, leading to treatment of patient by phlebotomy and/or cytotoxic drugs. In addition, a higher incidence of cancers is observed in PV patients, independently of treatment. These observations argue for an impaired immune response in PV. In order to investigate this hypothesis, we studied the distribution of lymphocyte subpopulations in PV, and showed a significant decrease in T, TCR γ/δ and B cells together with an increase in natural killer (NK) cells., (Copyright © 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Epigenetic drugs modify DNA methylation and are used in refractory anemia with excess of blasts (RAEB). These drugs may reactivate anti-oncogene expression and restore a normal phenotype instead of inducing antitumor toxicity, although they also have immunosuppressive effects on T-lymphocytes [1] In RAEB and acute myeloid leukemia, a defect in natural killer (NK) cell cytotoxicity has been shown, which relies on abnormal expression of activating receptors. Previous study has shown that 5-azacytidine impaired mRNA synthesis and induced apoptosis in NK cells [2]. In this study we investigated the effect of the demethylating drug 5-azacytidine (Vidaza(®)) on NK receptors with the hypothesis that demethylation of the promoters of activating NK receptor genes induces gene reactivation and thus may increase their expression.

Background: Abnormal NK phenotype and cytotoxic functions have been described in acute myeloid leukemia, chronic lymphocytic leukemia, myeloma and myelodysplastic syndromes. Defective NK cytotoxicity is due to decreased expression of the Natural Cytotoxicity Receptors (NCRs), 2B4/CD244/p38, or NKG2D. This prompted us to test the expression of these molecules on circulating NK cells from patients with AIDS-related lymphomas (RL) in comparison with HIV + patients without lymphoma, healthy subjects and HIV-negative patients with lymphoma., Methods: Blood samples were analyzed by flow cytometry for NCRs, 2B4/CD244/p38 and NKG2D expression on NK cells defined as CD3-/CD56+ lymphocytes. We also analyzed by quantitative PCR specific RNA for NKp30/NCR3 and NKp46/NCR1., Results: We could not detect any defect in NKp46/NCR1 expression between all groups. NKp44/NCR2, NKp30/NCR3 and NKG2D had lower expression in AIDS-RL in comparison with HIV + patients without lymphoma when compared to patients with similar (>0.3 G/L) CD4+ lymphocyte levels. Expression of 2B4/CD244/p38 was lower in AIDS-RL than in HIV-negative lymphoma. Comparison of specific NKp30/NCR3 and NKp46/NCR1 RNA showed increased steady state levels, despite decreased surface expression for NKp30/NCR3, suggesting abnormal post-transcriptional regulatory mechanisms., Conclusions: We show a more pronounced defect in NK activating molecule when HIV infection is associated with lymphoma than when only one condition (HIV positivity or lymphoma) is present. Defective NK phenotype, in addition to CD4+ depletion and dysfunction, may participate to the increased incidence of lymphoma in HIV patients.

In monoclonal gammopathies (MG) and multiple myeloma (MM), normal natural cytotoxicity receptors (NCR) expression (NCR1/NKp46, NCR2/NKp44, NCR3/NKp30) is observed in natural killer (NK) cells. Nonetheless, except in plasma cell leukemia, few tumor plasmocytes are present in PB, while NK studies have been performed on peripheral blood (PB). For this reason we focused our attention on NK from bone marrow (BM). Our study demonstrates that the down-regulation of NCR3/NKp30 is only detectable in NK from BM but not in PB, and shows a drastic decrease of both NKG2D and CD244/2B4/p38 expression in NK from BM in comparison with PB. In conclusion, our data more precisely describe the mechanism of immune escape of MG/MM from innate immunity since we show a drastic down regulation of 3 major activating NK receptors (NCR3/NKp30, NKG2D and CD244/2B4/p38) at the site of tumor, i.e BM, that was undetectable in PB. Further studies regarding immune regulatory drugs in MG/MM will imperiously require the assessment of immune cell status not only in PB but also in BM to obtain more relevant data regarding anti-tumor efficacy., (© 2013 John Wiley & Sons Ltd.)

Recent advances in chronic lymphocytic leukaemia (CLL) treatment, more particularly through upfront use of anti-CD20 monoclonal antibodies, have prolonged patient progression-free survival. Nonetheless, apart from allogeneic stem cell transplantation, no curative treatment is available. One possible explanation for the lack of cure in CLL could be a defective immune anti-tumour response. As the result of abnormal HLA class I molecule expression, CLL cells escape from specific T-lymphocyte immunity but should be the target for the innate natural killer (NK) cell-mediated immune response. Defective NK cytotoxicity as the result of decreased expression of the natural cytotoxicity receptors (NCRs) NKp30/NCR3, NKp44/NCR2 and NKp46/NCR1 has been described in haematological malignancies such as acute myeloid leukaemia. This prompted us to focus our attention on NCR expression on NK cells from patients with CLL. Although we failed to detect any difference between CLL patients and healthy age-matched controls, a precise analysis of clinical data showed a correlation between decreased NCR expression and poor prognosis factors such as low haemoglobin level, high (>30×10(9) per litre) lymphocyte count or elevated C-reactive protein. Together, these observations support the rationale for restoration of normal NK cell functions in patients with CLL, putatively through the use of immune therapy protocols that already have demonstrated some benefit in acute myeloid leukaemia such as interleukin-2 plus histamine dihydrochloride., (© 2011 The Authors. Immunology © 2011 Blackwell Publishing Ltd.)

Tissue factor pathway inhibitor (TFPI) plays a crucial role in haemostasis by regulating TF-induced initiation of coagulation. Since it is expressed by endothelial and trophoblastic cells, TFPI is of particular importance at the placental level and might be involved in the occurrence of gestational vascular complications (GVC). In the present study, we investigated plasma free TFPI antigen in four groups of women: healthy non-pregnant women without history of pregnancy complications; women at the beginning (<12 weeks) and women during the third trimester of a normal pregnancy; women with late pregnancy complications (pre-eclampsia / HELLP syndrome, intra-uterine fetal death, fetal growth retardation) at the time of obstetrical event and/or at distance from pregnancy. In normal pregnancy, TFPI increased between first trimester and delivery (median 5.0 ng/ml vs. 7.1 ng/ml; p<0.0001) but remained lower than in non-pregnant controls (median 8.2 ng/ml; p<0.0001). In patients, when measured concomitantly to the obstetrical event, TFPI showed no difference with normal late pregnancy levels. In contrast, at distance from pregnancy, in the absence of any hormonal influence, TFPI was significantly lower than in non-pregnant controls (median 5.9 vs. 8.2ng/ml, p < 0.0001). After categorisation into quartiles, an inverse dose-effect relationship was demonstrated between TFPI categories recorded apart from pregnancy and GVC risk, with a crude odds ratio of 43.5 (95% confidence interval 8.2-230) for patients with TFPI values in the lowest quartile (< 5.7 ng/ml). In conclusion, low free TFPI at distance from pregnancy appears to be a strong indicator of GVC risk.

Peripheral T-cell lymphomas constitute a heterogeneous group with regard to diagnosis, treatment and prognosis. Efforts have been made to combine novel techniques with cytology and immunochemistry in order to more precisely define these entities. Molecular profiling has contributed to novel insights in the biology of T-cell lymphoma. Regarding anaplastic large cell lymphoma, low expression T-cell receptor signalling and high STAT3 target signatures have been associated with the ALK-positive subgroup. Gene expression profiling differentiates angioblastic T-cell lymphoma from other T-cell malignancies, suggests that the normal counterpart of lymphoma cells are follicular helper T cells, and supports the involvement of vascular endothelial growth factor deregulation in its physiopathology. In peripheral T-cell lymphoma unspecified, gene profiling suggests the normal counterpart of tumour cells are activated CD4(+) or CD8(+) T-lymphocytes, delineates prognostic groups depending on the proliferative signature, and suggests therapeutic options aimed at regulating nuclear factor-kappaB and platelet-derived growth factor receptor-alpha phosphorylation. Gene expression profiling of primary cutaneous T cell lymphomas highlighted the importance of abnormal methylation patterns, suggested a pivotal role for JUNB/AP-1, and defined a predictive model for response to interferon-alpha. In conclusion, gene expression profiling is beginning to change the pathological classification, the prognosis profiles and the therapeutic approach in T-cell lymphomas.

Purpose: Gaucher disease is the most frequent lysosomal storage disease, and corresponds to an inherited deficiency of glucocerebrosidase. Due to excessive accumulation of glucocerebroside in bone marrow, cytopenia and bone lesions occur., Key Points: The clinical signs at diagnosis include frequently anaemia, thrombopenia and splenomegaly. The hematologist is often in first line of the diagnosis, but it must avoid certain diagnostic traps (pseudo-Gaucher cells or even pseudo-pseudo-Gaucher cells in certain crystal storage diseases). The treatment of substitution when adequately carried out generally makes it possible to quickly improve the hematologic parameters. Another hematologic aspect must be evoked in Gaucher disease, i.e. the incidence of associated malignant pathologies and more particularly of multiple myeloma. Many cases of association between multiple myeloma and Gaucher disease have been reported in the literature. Recently two important series demonstrated the nonfortuitous character of this association., Projects: The physiopathological links which could connect myeloma and Gaucher disease are not known to date. Immune network imbalance could be an interesting hypothesis that should require further investigations.

Gaucher disease (GD) is the most frequent lysosomal storage disease and corresponds to an inherited deficiency of glucocerebrosidase. Due to excessive accumulation of glucocerebroside in bone marrow, both cytopenia and bone lesions may occur. The incidence of malignant disorders has been evoked in non-neuronopathic type I GD. More particularly, many case reports have been published that describe the association between GD and multiple myeloma (MM). Here, we first deal with diagnosis criteria that allow to distinguish between bona fide Gaucher celles and the so-called pseudo or pseudo-pseudo Gaucher cells. We then analyse relevant case reports and recent articles that provide convincing data regarding GD and MM association and suggest physiopathological links between the two disorders.

Moderate hematologic abnormalities, like anemia or leukopenia, are frequently seen in anorexia nervosa, whereas pancytopenia and bone marrow abnormalities are uncommon. We report a case of tricytopenia with gelatinous bone marrow transformation in anorexia nervosa. Marrow gelatinous transformation (also called serous fat atrophy or starvation marrow) is characterized by the association of marrow hypoplasia and interstitial infiltration of a ground gelatinous substance (acidic mucopolysaccharides). Changes in peripheral blood cell counts are various and moderate, and do not always reflect the severity of bone marrow damage. The pathogenesis is not yet well elucidated but is certainly related to the nutritional status because gelatinous bone marrow transformation is found in anorexia nervosa and in other clinical situations with cachexia. Gelatinous transformation of the marrow is reversible with feeding.

A 55-year-old man was treated during 22 months with chlorambucil (total dose : 4 218 g) for glomerulonephritis. Towards the end of the treatment, he developed acute myelomonocytic leukaemia and died of this complication. The authors underline the oncogenetic dangers of the association dysimmune disease/immunosuppressive treatment and draw attention to the almost regular preleukaemic phase with its well-known cytological, biochemical, immunological, cytogenetic and evolutive criteria.

A trial of immunotherapy in the maintenance treatment of non-lymphoblastic acute leukaemias led to a comparison of 2 groups of patients in complete remission. Group C (14 patients) received only monthly reinduction chemotherapy. Group C + I (17 patients) received identical chemotherapy together with weekly immunotherapy combining BCG and irradiated leukaemic cells. Whilst the duration of the first remission was unmodified, the overall survival and above all survival after the first recurrence were prolonged in group C + I. These results were all the more marked when a homogeneous patients having received the same induction chemotherapy is considered.