Thromboembolic events in patients with paroxysmal nocturnal hemoglobinuria (PNH): Real world data of a Greek nationwide multicenter retrospective study.

Thrombosis is the most common and a life-threatening complication in patients with Paroxysmal Nocturnal Hemoglobinuria. One-third of patients with PNH experience at least one thromboembolic event during the course of the disease, with thrombosis being the most common cause of death in these patients. The mechanism of thrombosis in PNH is complex and continues to be of great research interest. Since the introduction of C5 complement inhibitors in the treatment of PNH, the incidence of thromboembolic events has decreased substantially. We retrospectively analyzed data concerning the thrombotic episodes of 41 patients with PNH from 14 different national hematology centers in Greece. Sixteen patients (39%) experienced at least one episode of thrombosis, including, seven (43.8%) at diagnosis, seven (43.8%) during the course of the disease and two (12.5%) patients prior to PNH diagnosis. Nearly half of these individuals (n=7, 43.8%) had multiple episodes of thrombosis during the course of their disease. The most common sites of thrombosis were intra-abdominal veins. Three out of 26 patients developed thrombosis while on eculizumab. In none of the 16 patients, the thrombotic event was fatal. Our findings, despite the small number of patients, confirmed that thrombosis continues to be a significant complication of PNH affecting more than one third of the patients.

CXCR3 axis in patients with primary biliary cirrhosis: a possible novel mechanism of the effect of ursodeoxycholic acid.

The CXC chemokines, monokine induced by interferon (IFN)-gamma (MIG) (CXCL9), IFN-gamma-induced protein 10 (IP-10) (CXCL10) and IFN-inducible T cell alpha chemoattractant (I-TAC) (CXCL11), are known to attract CXCR3- (CXCR3A and CXCR3B) T lymphocytes. We investigated MIG, IP-10 and I-TAC mRNAs expression by semi-quantitative multiplex reverse transcription-polymerase chain reaction (RT-PCR) in liver biopsies obtained from patients with a first diagnosis of primary biliary cirrhosis [(PBC) = 20] compared to patients with normal liver biopsy [normal controls (NCs) = 20]. Chemokine production was assessed by enzyme-linked immunosorbent assay (ELISA) in serum. Measurements were repeated 6 months after ursodeoxycholic acid (UDCA) treatment in PBC patients. CXCR3A and CXCR3B mRNAs expression was examined in immunomagnetically sorted CD3(+) peripheral blood lymphocytes (PBL) pre- and post-treatment by RT-PCR. Flow cytometry was used to evaluate the expression of CXCR3(+) PBLs of NCs and PBC patients. A marked mRNA expression of MIG and IP-10 was found in PBC patients. I-TAC mRNA was not detected. In serum of PBC patients there was a significant increase of MIG and IP-10 compared to NCs. Interestingly, there was a significant reduction of these proteins in patients' serum after UDCA treatment. I-TAC was not statistically different between groups. CXCR3A mRNA expression was found in PBLs from PBC patients as well as in NCs. CXCR3B mRNA was expressed in four of 20 (19%) NCs and 20 of 20 PBC patients. Flow cytometry revealed a significantly lower CXCR3 expression in NCs (13·5%) than in PBC (37·2%), which was reduced (28·1%, P < 0·01) after UDCA administration. These data suggest a possible role for CXCR3-binding chemokines and their receptor in the aetiopathogenetic recruitment of lymphocytes in PBC and a new mechanism of action for UDCA.

Increased expression of chemokine receptor CCR3 and its ligands in ulcerative colitis: the role of colonic epithelial cells in in vitro studies.

Human colonic epithelial cells express T helper type 1 (Th1)-associated chemoattractants, yet little is known about the production of Th2-associated chemoattractants. CCL11/eotaxin-1, CCL24/eotaxin-2 and CCL26/eotaxin-3 are known to attract CCR3-expressing, Th2-polarized lymphocytes. We studied constitutive and inflammation-induced expression and production of CCR3 together with its ligands in the colon and peripheral blood of patients with inflammatory bowel disease (IBD) by flow cytometry, reverse transcription­polymerase chain reaction (RT­PCR) and enzyme-linked immunosorbent assay (ELISA). We further defined the regulated expression of these chemokines by RT­PCR and ELISA using cultured human epithelial cell lines. A higher fraction of peripheral T lymphocytes were found to be positive for CCR3 in patients with ulcerative colitis (UC) compared to Crohn's disease (CD), while almost no CCR3(+) T cells were found in normal controls (NC). Similarly, higher and more frequent expression of CCR3 was observed in colonic biopsies from patients with UC, regardless of the disease activity, when compared to CD or NCs. Serum CCL11/eotaxin-1 was increased significantly in UC (306 ± 87 pg/ml) and less so in CD (257 ± 43 pg/ml), whereas CCL24/eotaxin-2, and CCL26/eotaxin-3 were increased only in UC. Colonic expression of the three chemokines was minimal in NCs but high in inflammatory bowel diseases (especially UC) and was independent of disease activity. Th2, and to a lesser extent Th1, cytokines were able to induce expression and production of all three eotaxins from colonic epithelial cells in culture. CCR3 and ligands over-expression would appear to be a characteristic of UC. The production of CCR3 ligands by human colonic epithelial cells suggests further that epithelium can play a role in modulating pathological T cell-mediated mucosal inflammation.

Microtubule-interacting drugs induce moderate and reversible damage to human bone marrow mesenchymal stem cells.

OBJECTIVES: This study aimed to investigate molecular and cellular changes induced in human bone marrow mesenchymal stem cells (hMSCs) after treatment with microtubule-interacting agents and to estimate damage to the bone marrow microenvironment caused by chemotherapy. MATERIALS AND METHODS: Using an in vitro hMSC culture system and biochemical and morphological approaches, we studied the effect of nocodazole and taxol(R) on microtubule and nuclear envelope organization, tubulin and p53 synthesis, cell cycle progression and proliferation and death of hMSCs isolated from healthy donors. RESULTS AND CONCLUSIONS: Both nocodazole and taxol reduced hMSC proliferation and induced changes in the microtubular network and nuclear envelope morphology and organization. However, they exhibited only a moderate effect on cell death and partial arrest of hMSCs at G(2) but not at M phase of the cell cycle. Both agents induced expression of p53, exclusively localized in abnormally shaped nuclei, while taxol, but not nocodazole, increased synthesis of beta-tubulin isoforms. Cell growth rates and microtubule and nuclear envelope organization gradually normalized after transfer, in drug-free medium. Our data indicate that microtubule-interacting drugs reversibly inhibit proliferation of hMSCs; additionally, their cytotoxic action and effect on microtubule and nuclear envelope organization are moderate and reversible. We conclude that alterations in human bone marrow cells of patients under taxol chemotherapy are transient and reversible.

Functional, molecular and proteomic characterisation of bone marrow mesenchymal stem cells in rheumatoid arthritis.

OBJECTIVE: Bone marrow (BM) mesenchymal stem cells (MSCs) are being considered as potential therapeutic agents in various inflammatory autoimmune diseases for their tissue-repair and anti-inflammatory tissue-protective properties. This study investigates the reserves and function, the molecular and proteomic profile and the differentiation potential of BM MSCs in patients with active rheumatoid arthritis (RA). METHODS: We evaluated the frequency of MSCs in the BM mononuclear cell fraction using a limiting dilution assay, the proliferative/clonogenic potential and the capacity of cells to differentiate towards the osteogenic/chondrogenic/adipogenic lineages using appropriate culture conditions. We also assessed the molecular and proteomic characteristics in terms of inflammatory cytokine gene and protein expression, the relative telomere length and the survival characteristics of BM MSCs. RESULTS: MSCs from patients with RA (n = 26) and age- and sex-matched healthy individuals (n = 21) were similar in frequency, differentiation potential, survival, immunophenotypic characteristics, and protein profile. Patient MSCs, however, had impaired clonogenic and proliferative potential in association with premature telomere length loss. Transcriptome analysis revealed differential expression of genes related to cell adhesion processes and cell cycle progression beyond the G1 phase. Previous treatment with methotrexate, corticosteroids, anti-cytokine and biological agents or other disease-modifying anti-inflammatory drugs did not correlate with the clonogenic and proliferative impairment of BM MSCs. CONCLUSION: In spite of some restrictions related to the impaired clonogenic and proliferative potential, our findings support the use of autologous BM MSCs in RA and may have important implications for the ongoing efforts to repair tissue injury commonly seen in the course of the disease.

An improved method for the diagnostic approach of alpha+-thalassaemia.

An improved method for the diagnostic approach of alpha(+)-thalassaemia is described. The method is based on five common parameters: absence of iron deficiency, mild morphological abnormalities of erythrocytes, normal or slightly reduced erythrocytic indices MCV and MCH, normal chromatographic findings, and presence of haemoglobin H inclusions in erythrocytes with methyl-violet stain after, but not before, incubation with oxidant agent. We studied by DNA analysis, 58 subjects fulfilling the above mentioned diagnostic criteria and we found that 50 of them (86.2%) had a alpha-globin gene defect. In the remaining eight subjects (13.8%) no alpha-gene defect could be documented with the techniques used in the DNA analysis, which detect the six well-known alpha(+)-thalassaemic defects in the Greek population. We conclude that the improved method, we described has a high sensitivity and accuracy in the screening of alpha(+)-thalassaemia.

Changes in maternal plasma levels of VEGF, bFGF, TGF-beta1, ET-1 and sKL during uncomplicated pregnancy, hypertensive pregnancy and gestational diabetes.

BACKGROUND: Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), transforming growth factor-beta1 (TGF-beta1), endothelin-1 (ET-1) and soluble c-kit ligand (sKL) are cytokines involved in embryogenesis. MATERIALS AND METHODS: Maternal plasma cytokines were measured with ELISA during the three trimesters of gestation and on the day of delivery in 93 pregnant women and 18 age-matched non-pregnant control women. RESULTS: The VEGF and bFGF levels increased during the first trimester and declined thereafter, but they remained above the controls' values until delivery. The TGF-beta1 levels increased during the first trimester and remained unchanged thereafter. On the contrary, the ET-1 levels decreased and remained low until delivery. VEGF, bFGF, TGF-beta1 and ET-1 were increased in hypertensive pregnancy. Except for ET-1, these cytokines were also increased in gestational diabetes. No changes in plasma sKL were documented. CONCLUSION: All the aforementioned cytokines play a role in uncomplicated pregnancy, whereas hypertensive pregnancy is causatively-related with increased ET-1.

Normal bone marrow hematopoietic stem cell reserves and normal stromal cell function support the use of autologous stem cell transplantation in patients with multiple sclerosis.

Bone marrow (BM) stem cell reserves and function and stromal cell hematopoiesis supporting capacity were evaluated in 15 patients with multiple sclerosis (MS) and 61 normal controls using flow cytometry, clonogenic assays, long-term BM cultures (LTBMCs) and enzyme-linked immunosorbent assays. MS patients displayed normal CD34+ cell numbers but a low frequency of colony-forming cells (CFCs) in both BM mononuclear and purified CD34+ cell fractions, compared to controls. Patients had increased proportions of activated BM CD3+/HLA-DR+ and CD3+/CD38+ T cells that correlated inversely with CFC numbers. Patient BM CD3+ T cells inhibited colony formation by normal CD34+ cells and patient CFC numbers increased significantly following immunomagnetic removal of T cells from BMMCs, suggesting that activated T cells may be involved in the defective clonogenic potential of hematopoietic progenitors. Patient BM stromal cells displayed normal hematopoiesis supporting capacity indicated by the CFC number in the nonadherent cell fraction of LTBMCs recharged with normal CD34+ cells. Culture supernatants displayed normal stromal derived factor-1 and stem cell factor/kit ligand but increased flt-3 ligand levels. These findings provide support for the use of autologous stem cell transplantation in MS patients. The low clonogenic potential of BM hematopoietic progenitors probably reflects the presence of activated T cells rather than an intrinsic defect.

Activated T-lymphocytes with myelosuppressive properties in patients with chronic idiopathic neutropenia.

To characterize the cellular components responsible for the impaired granulopoiesis in chronic idiopathic neutropenia (CIN), we investigated the origin of the proapoptotic cytokine producing cells in the bone marrow (BM) microenvironment of CIN patients. We found that the interferon gamma (IFN gamma) and/or Fas-ligand expressing cells in patient BM mononuclear cells and long-term BM culture stroma cells were the CD3(+) T-lymphocytes but not the CD14(+) monocytes/macrophages. The percentage of activated T-lymphocytes was increased in patients' BM as indicated by the proportions of human leucocyte antigen (HLA)-DR(+), CD25(+), CD38(+), CD69(+) and Fas(+) cells within the CD3(+) fraction. Intracellular IFN gamma expression was higher in the BM than peripheral blood of the patients and was associated with increased BM T-lymphocyte numbers. In crossover experiments, patient CD3(+) T-lymphocytes conferred autologous and allogeneic haemopoietic progenitor cell colony inhibition. Patients' T-cell receptor repertoire and polymerase chain reaction analysis did not reveal any clonal T-lymphocyte expansion, suggesting the absence of a direct, antigen-driven recognition of CD34(+) myeloid progenitor cells by patient T-lymphocytes. We conclude that CIN patients have increased number of activated T-lymphocytes in the BM, probably in the setting of a localized polyclonal immune reaction and that these cells confer an inhibitory effect on myelopoiesis through myelosuppressive cytokines including Fas-ligand and IFN gamma.

Acute myeloid/NK precursor cell leukemia with trisomy 4 and a novel point mutation in the extracellular domain of the G-CSF receptor in a patient with chronic idiopathic neutropenia.

Chronic idiopathic neutropenia (CIN) has been well recognized as a granulocytic disorder not associated with increased risk to malignant transformation. Four cases, however, of acute myeloid leukemia have been recently reported in patients with CIN. In the current paper, we report on a CIN patient who developed acute myeloid/natural killer (NK) precursor cell leukemia 11 years after diagnosis and 4 months after initiation of treatment with recombinant human granulocyte colony-stimulating factor (rhG-CSF). Leukemic cells had trisomy 4 as the sole cytogenetic abnormality and, also, a novel point mutation in the extracellular domain of the G-CSF receptor (G-CSFR) leading to truncated protein with a loss of 36 amino acids. There was no evidence that this receptor transmitted signals even in the presence of high doses of rhG-CSF in the cultures. We consider that CIN may be a preleukemic condition, at least in a subset of patients, and that rhG-CSF administration is unlikely to be involved in the leukemic transformation in this patient, although such a possibility could not be completely ruled out.

Increased cell apoptosis in bone marrow trephine biopsies and immunomagnetically isolated myeloid progenitor cells in patients with chronic idiopathic neutropenia.

The frequency of apoptotic cells in bone marrow trephine biopsies and cytospins of immunomagnetically isolated myeloid progenitor cells was determined in 39 patients with chronic idiopathic neutropenia (CIN) and 12 hematologically normal individuals using the in situ end-labeling (ISEL) apoptosis detection method. We found that 66.7% of the patients but none of the normal controls displayed apoptotic cells equal to or higher than 5% of the total mononuclear cells in bone marrow biopsies (p<0.01). In the double stain, we also found that the proportion of apoptotic CD15(+) myeloid precursor cells did not differ significantly between patients and control subjects, while the proportion of apoptotic CD34(+) hemopoietic cells could not be estimated with accuracy because of the presence of CD34(+) endothelial cells. Significantly increased apoptosis was noted in cytospins of immunomagnetically isolated patient CD34(+) and CD34(+)/CD33(+) cells but not CD34(-)/CD33(+) cells, compared to the controls ( p<0.001, p<0.02 and p>0.05, respectively). These findings confirm and extend our previous observations in flow-cytometric studies of apoptosis in CIN, indicating that increased apoptosis in CIN bone marrow concerns mainly the CD34(+) and CD34(+)/CD33(+) progenitor cell compartments. We conclude that the accelerated apoptosis in these compartments may account for the impaired neutrophil production in CIN patients.

Complete regression of primary gastric plasmacytoma following Helicobacter pylori eradication.

We describe the first case of a primary gastric plasmacytoma stage I completely regressed following Helicobacter pylori (H.pylori) eradication. The patient, a 61-year-old man, had a long history of chronic gastritis and gastric ulcers with recurrent gastrointestinal hemorrhage. Diagnosis of H.pylori infection was based on the positive urease breath test, the elevated titers of serum anti- H.pylori antibodies, and the detection of the bacterium in gastric mucosa biopsy specimens. Diagnosis of gastric plasmacytoma was based on the findings of histopathology, immunocytochemistry and in situ hybridization. Eradication of H.pylori with antibiotics was followed by disappearance of endoscopic and histopathologic features of the gastric tumor 3 months after the completion of the treatment. No relapse has been documented 20 months after the initial diagnosis of plasmacytoma. A possible causal relationship between the tumor and the underlying H.pylori infection is discussed.

Non-Hodgkin's lymphoma in patients with systemic lupus erythematosus.

Two cases of non-Hodgkin's lymphoma (NHL) associated with systemic lupus erythematosus (SLE) are described. Patient-1 was a 65-year-old woman in whom SLE and diffuse large B-cell lymphoma were concurrently diagnosed. The patient presented with low-grade fever, butterfly rash, arthritis and generalized lymphadenopathy without splenomegaly or bone marrow involvement. Complete remission of NHL and SLE was achieved with cyclophosphamide, adriamycin, vincristine and prednisone. Patient-2 was a 56-year-old woman in whom SLE had been diagnosed 14 years earlier. The patient presented with low-grade fever, bulky splenomegaly without lymphadenopathy, IgMA paraproteinemia, and expansion of a monoclonal CD19+/CD22+ lambda-type B-cell population in both bone marrow and peripheral blood. Diagnosis of a lympho-plasmacytoid lymphoma was established histologically after splenectomy. A partial remission of the neoplasm was achieved with cyclophosphamide, vincristine and prednisone. We suggest that the development of NHLs in patients with SLE may not be coincidental and we recommend the search for NHL in cases of SLE with prominent lymphadenopathy, massive splenomegaly or expansion of a monoclonal CD19+/CD22+ B-cell population.

Two patients with nonimmune chronic idiopathic neutropenia of adults developing acute myeloid leukemia with aberrant phenotype and complex karyotype but no mutations in granulocyte colony-stimulating factor receptor.

It has been suggested that some cases of nonimmune chronic idiopathic neutropenia of adults (NI-CINA) may be considered preleukemic disorders. This paper describes two patients with NI-CINA who developed acute myeloid leukemia (AML) 34 and 64 months, respectively, following NI-CINA diagnosis. Patient 1 presented erythema nodosum and patient 2 polyarthritis of the large joints 9 and 2 months, respectively, before AML. Patient 1 had AML M4 disease associated with aberrant expression of CD7 and CD19 cell surface markers and one abnormal clone in bone marrow karyotype. Patient 2 had myeloid/natural killer (NK) cell leukemia with expression of CD7 and CD56 molecules and four derivative abnormal clones in the karyotype. Both patients had del(5)(q22q35) in common. No mutations in the transmembrane or the intracytoplasmic domain of the granulocyte colony-stimulating factor (G-CSF) receptor were found. The first patient had disease resistant to chemotherapy from the beginning of the treatment and the second following a brief complete hematological remission. On the basis of these observations, we concluded that a causal link of AML with the underlying NI-CINA cannot be presently justified, but the unusual findings noted in our patients prompt the description of additional cases for a further investigation of the relationships, if any, between these two granulocytic disorders.

Increased apoptosis of bone marrow CD34(+) cells and impaired function of bone marrow stromal cells in patients with systemic lupus erythematosus.

The changes in bone marrow (BM) stem cell reserve and function and stromal cell function in patients with active systemic lupus erythematosus (SLE) were investigated. The study was carried out on seven SLE patients and 28 healthy controls using flow cytometry and in vitro cell culture assays. We found that patients had low CD34(+) cells, compared with the control group, reflecting the decrease of both CD34(+)/CD38(-) and CD34(+)/CD38(+) cells. Patient CD34(+)/Fas(+) but not CD34(-)/Fas(+) cells were significantly increased. Apoptotic (7AAD(dim)) cells were higher among CD34(+)/Fas(+) than among CD34(+)/Fas(-) cells, and individual values of apoptotic CD34+ cells strongly correlated with the number of CD34(+)/Fas(+) cells. These findings are suggestive of a Fas-mediated apoptosis accounting for the low CD34(+) cells in SLE patients. Moreover, we found that patients had low numbers of granulocyte-macrophage colony-forming units (CFU-GM) and erythroid burst-forming units (BFU-E), compared with the control group, and that the generation of colony-forming cells in long-term BM cultures was significantly reduced. Patient BM stroma failed to support allogeneic progenitor cell growth. In one patient, CD34(+) cells were increased, apoptotic CD34(+)/Fas(+) cells were normalized and defective stromal cell function was restored after autologous stem cell transplantation. We concluded that defective haemopoiesis in SLE patients is probably caused, at least in part, to the presence of autoreactive lymphocytes in BM.

Non-immune chronic idiopathic neutropenia of adult: an overview.

There is strong evidence that non-immune chronic idiopathic neutropenia of adult is a cytokine-mediated syndrome characterized by (a) neutropenia of varying degree associated with a low number of lineage-specific CD34+ cells and increased production of inhibitors of hematopoiesis, including transforming growth factor-beta1 and tumor necrosis factor-alpha; (b) lymphopenia due to selective loss of primed/memory T-cells and NK cells; (c) increased splenic volume on ultrasonography in 48.1% of patients; (d) osteopenia and/or osteoporosis in 60.0% of patients; (e) anemia, mostly of the type of anemia of chronic disease, in 15.6% of patients; (f) features of chronic antigenic stimulation, including increased proportion of bone marrow plasma cells, increased serum levels of IgG1 and/or IgA, increased frequency of monoclonal gammopathy of undetermined significance, increased frequency of antinuclear antibodies with specific reactivity, and increased serum levels of circulating immune complexes; and (g) increased concentrations of a variety of macrophage-derived pro-inflammatory cytokines and chemokines capable of affecting bone metabolism, bone marrow function, and leukocyte trafficking. All these findings are suggestive of the existence of an unrecognized low-grade chronic inflammatory process which may be involved in the pathogenesis of the disorder. Neutropenia in these patients is probably the result of a combination of at least three factors, reduced neutrophil production in bone marrow, enhanced neutrophil extravasation, and increased sequestration and/or extravasation of neutrophils into the spleen.