Epstein-Barr virus-driven B Cell Proliferation with CD4+ T Cell Expansion: A Lymphomatoid Granulomatosis-like Disease Related to Hyperinterleukin-10 Secretion of Remarkably Favourable Outcome with Rituximab.

Granulomatous lymphomatosis is an Epstein-Barr virus (EBV)-driven B cell proliferation associated with an exuberant CD4(+) T cell reaction with usually histopathological pictures of angiocentrism. So far, the characteristics of CD4(+) T cells in granulomatous lymphomatosis and the mechanism leading to their expansion remain poorly explored. We report a 56-year-old female with a past history of cold agglutinin disease, which was successfully treated with 4 weekly infusions of rituximab. She presented one year later with features of granulomatous lymphomatosis that resulted in severe lung and bone marrow infiltration. We provide evidence that CD4(+) T cell expansion was oligoclonal, involved anergic cells and did not result from an EBV-driven stimulation. Rather, it resulted possibly from a high production of interleukin-10 by immunoblastic EBV-positive B cells. The outcome was remarkably favourable with rituximab and steroids. Our results suggest that an EBV-driven B cell proliferation should be investigated in patients presenting with a CD4(+) T cells alveolitis or other systemic manifestations resulting from a CD4(+) T cell expansion. These features should prompt to introduce an immunosuppressive therapy including steroids and rituximab. Our results deserve further investigations to confirm our pathophysiological hypotheses in CD4(+) T cell expansions associated with EBV-driven B cell proliferations and to assess whether granulomatous lymphomatosis could result from comparable mechanisms.

[Lymphocytopenia: aetiology and diagnosis, when to think about idiopathic CD4(+) lymphocytopenia?]. / Démarche diagnostique devant une lymphopénie : quand penser à la lymphopénie CD4(+) idiopathique ?

Lymphocytopenia is defined by a lymphocyte count less than 1500/mm(3) in adults and less than 4500/mm(3) in children before the age of 8 months. Lymphocytopenia can be global or selectively affect a peculiar lymphocyte subpopulation. The patient's age, the context as well as the associated clinical manifestations and treatment prescribed must be taken into account in order to identify the etiology of lymphocytopenia. In adults, lymphocytopenia can be caused by: (1) insufficient thymic output (primary immune deficiencies, corticosteroid treatment, zinc deficiency, etc.), (2) increased lymphocyte catabolism (radiotherapy, chemotherapy, immunosuppressant, HIV infection, systemic lupus, etc.), (3) modified lymphocyte distribution (viral infections, septic shock, extensive burns, splenomegaly, granulomatosis, etc.), (4) multifactorial or unknown etiology (end-stage renal disease, lymphoid malignancies, solid tumor, ethnicity, etc.). In children, in addition to these etiologies, other immune deficiencies may be responsible for severe lymphocytopenia (thymocytes apoptosis, cytokine deficiencies, altered B-cell and T-cell receptor synthesis, signal transduction and cellular interactions deficiencies). Idiopathic CD4(+) lymphocytopenia is a rare disorder. It is defined by a persisting lymphocyte CD4(+) count less or equal to 300/mm(3) or less or equal to 20% of total lymphocytes in the absence of alternative diagnosis. Clinical symptoms can be absent or include opportunistic infections, auto-immune manifestations, lymphoma or solid tumors. Treatment is similar to that of HIV-infected patients and sometimes relies on specific immunotherapy even though clinical benefit has not been evaluated.

Evidence for a protective role of the STAT5 transcription factor against oxidative stress in human leukemic pre-B cells.

STAT5 transcription factors are involved in normal B lymphocyte development and in leukemogenesis. We show that the inhibition of STAT5A expression or activity in the NALM6, 697 and Reh leukemic pre-B cell lines, results in a higher spontaneous apoptosis and an increased FAS-induced cell death. However, the molecular mechanisms underlying the altered pre-B cell survival are unclear. We used a proteomic approach to identify proteins that are differentially regulated in cells expressing (NALM6Δ5A) or not a dominant negative form of STAT5A. Among the 14 proteins identified, six were involved in the control of the oxidative stress like glutathione (GSH) synthetase and DJ-1. Accordingly, we showed increased levels of reactive oxygen species (ROS) in NALM6Δ5A cells and suppression of the increased sensitivity to Fas-mediated apoptosis by the GSH tripeptide. Similar results were observed when NALM6 cells were treated with TAT-STAT5Δ5A fusion proteins or STAT5A shRNA. In addition, the 697 and Reh pre-B cells were found to share number of molecular changes observed in NALM6Δ5A cells including ROS generation, following inhibition of STAT5 expression or function. Our results point out to a hitherto undescribed link between STAT5 and oxidative stress and provide new insights into STAT5 functions and their roles in leukemogenesis.

Factors influencing disease phenotype and penetrance in HFE haemochromatosis.

Haemochromatosis is predominantly associated with the HFE p.C282Y homozygous genotype, which is present in approximately 1 in 200 people of Northern European origin. However, not all p.C282Y homozygotes develop clinical features of haemochromatosis, and not all p.C282Y homozygotes even present abnormal iron parameters justifying venesection therapy. This situation was not apparent from initial genotype/phenotype correlation studies as there was a selection bias of patients. Only those patients with a significant iron burden were included in these early studies. It is now largely accepted that the p.C282Y/p.C282Y genotype is necessary for the development of HFE haemochromatosis. However, this genotype provides few clues as to why certain symptoms are associated with the disease. Expression of iron overload in people with this genotype depends on the complex interplay of environmental factors and modifier genes. In this review, we restrict our discussion to work done in humans giving examples of animal models where this has helped clarify our understanding. We discuss penetrance, explaining that this concept normally does not apply to autosomal recessive disorders, and discuss the usefulness of different biochemical markers in ascertaining iron burden. Hepcidin, a peptide synthesized primarily by the liver, has been identified as the central regulator in iron homeostasis. Consequently, understanding its regulation is the key. We conclude that the main goal now is to identify important modifiers that have a significant and unambiguous effect on iron storage.

STAT3 transcription factor is constitutively activated and is oncogenic in nasal-type NK/T-cell lymphoma.

Nasal-type natural killer (NK) cell lymphoma is an infrequent aggressive malignant disease with very poor prognosis. We aimed to explore the possible role of the transcription factor STAT3 in the pathophysiology of this malignancy, as it was involved in oncogenesis and chemoresistance. For this, we established and characterized a continuous interleukin 2-dependent NK cell line (MEC04) from a patient with a fatal nasal-type NK-cell lymphoma. Cells harbored poor cytotoxic activity against K562 cells, and spontaneously secreted interferon-gamma, interleukin-10 and vascular-endothelium growth factor in vitro. STAT3 was phosphorylated in Y705 dimerization residue in MEC04 cells and restricted to the nucleus. Y705 STAT3 phosphorylation involved JAK2, as exposure of cells to AG490 inhibitor inhibited Y705 STAT3 phosphorylation. By using recombinant transducible TAT-STAT3-beta (beta isoform), TAT-STAT3Y705F (a STAT3 protein mutated on Y705 residue, which prevents STAT3 dimerization) and peptides inhibiting specifically STAT3 dimerization, we inhibited STAT3 phosphorylation and cell growth, with cell death induction. Finally, STAT3 was phosphorylated in Y705 residue in the nuclei of lymphoma cells in eight/nine patients with nasal-type NK/T-cell lymphoma and in YT, another NK cell line. Our results suggest that STAT3 protein has a major role in the oncogenic process of nasal-type NK-cell lymphomas, and may represent a promising therapeutical target.

The Src tyrosine kinase Hck is required for Tel-Abl- but not for Tel-Jak2-induced cell transformation.

Tel-Abl and Tel-Jak2 are fusion proteins associated with human haematologic neoplasms. They possess constitutive tyrosine kinase activity and activate common downstream signalling pathways like Stat-5, PI3-K/Akt, Ras/MapK and NF-kappaB. In this study, we showed the specific requirement of Src family members for the Tel-Abl-mediated cell growth, activation of Stat5, PI3-K/Akt and Ras/MapK while dispensable for Tel-Jak2. Hck was found strongly phosphorylated in Tel-Abl-expressing Ba/F3 cells and sensitive to imatinib mesylate treatment, providing evidence that Hck is a target of Tel-Abl tyrosine kinase activity. Overexpression of a kinase dead form of Hck inhibits the proliferation of Ba/F3 cells expressing Tel-Abl as the phosphorylation of Akt and Erk1/2. These results argue for an important role of Hck in Tel-Abl oncogenic signalling.

Successful treatment of osteolytic epithelioid hemangioendothelioma with pamidronate.

We describe the case of a 70-year-old man with unicentric grade 1 epitheloid hemangioendothelioma (EH) of the bone that favourably responded to intravenous pamidronate as a single agent. After 6 years of follow-up, the patient was in complete remisssion. We suggest that use of bisphosphonates should be considered in the treatment of osteolytic EH.

[Hemophagocytosis associated with an Escherichia coli sepsis: a case report]. / Syndrome d'activation macrophagique associé à une septicémie à Escherichia coli: à propos d'un cas.

INTRODUCTION: Hemophagocytic lymphohistiocytosis syndrome (HLS) is defined by activated macrophage proliferation. These cells phagocyte the blood elements. This syndrome can be primary as an autosomal recessive disease or secondary to neoplasia, immune diseases or infections-viral, parasitary or bacterian. CASE: Our case concerns an association of HLS and Escherichia coli (E. coli) sepsis in a metastatic prostatic cancer. The evolution was rapidly improved by antibiotics alone. The clinical and biological aspects as well as the differential diagnosis are discussed. CONCLUSION: The HLS is fatal. It can be caused by a severe infection, even an E. coli sepsis. The treatment focused on etiology can be sufficient.

Primary Sjögren's syndrome associated agranulocytosis: a benign disorder?

OBJECTIVE: To report on an uncommon association of agranulocytosis in primary Sjögren's syndrome (SS). METHODS: The clinical, haematological, and immunological features of seven patients with primary SS associated with a chronic (>6 months) agranulocytosis, and the outcome of the patients, were analysed. RESULTS: Patients were white women with an unexplained agranulocytosis. They all had non-erosive arthritis and three had a thrombocytopenia or Evan's syndrome. In three patients, transient or durable expansion of T lymphocytes was present in the peripheral blood or in the bone marrow, but evolved independently from neutrophil counts. There was no paroxysmal nocturnal haemoglobinuria clone or antibodies to neutrophil surface antigens. In vitro bone marrow culture was normal (four patients) or showed a decrease in colony forming unit-granulocyte monocyte (CFU-GM) and colony forming unit-erythroblast (CFU-E) (one patient). Serum levels of soluble Fas ligand (sFasL) were normal, and granulocyte-colony stimulating factor (G-CSF) concentrations were either normal or raised. One patient was treated with steroids associated with intravenous immunoglobulins and achieved a lasting response. Two other patients were treated with steroids and methotrexate, with poor efficacy. Short courses of subcutaneous G-CSF produced a transient and mild response in all three patients. Complete recovery of the neutrophils occurred temporarily during pregnancy in two patients. After a mean follow up of 34.8 months (range 6-139) all patients were alive and none developed serious infections. CONCLUSION: A subset of patients with primary SS and non-destructive arthritis may develop a chronic but well tolerated agranulocytosis that is usually poorly responsive to steroids and oral methotrexate.

Inflammatory myositis associated with anti-U1-small nuclear ribonucleoprotein antibodies: a subset of myositis associated with a favourable outcome.

OBJECTIVES: Inflammatory myositides are rare chronic disorders which may be either isolated or associated with other conditions such as connective tissue diseases or neoplasia. A large variety of autoantibodies can be detected in patients with myositis, some of which have a diagnostic and/or a prognostic value. Myositis associated with anti-U1-small nuclear ribonucleoprotein antibodies (anti-U1-snRNP Abs) are usually considered as overlapping syndromes, mainly mixed connective tissue diseases (MCTD) in which muscle symptoms occur insidiously during the disease course and are characterized by a favourable outcome. METHODS: The clinical, biological, immunological and pathological findings as well as the outcome of five patients with anti-U1-snRNP-associated myositis were retrospectively analysed. RESULTS: Patients were mainly black females. In all five patients, myositis was the predominant manifestation at presentation. Associated conditions consisted of interstitial lung disease (ILD) (three), arthritis (three) and neurological symptoms (two). No patient presented Raynaud's phenomenon nor met criteria for MCTD. Biological inflammatory features, rheumatoid factor and polyclonal hypergammaglobulinaemia were present in all cases. Besides anti-U1-snRNP Abs, one patient had anti-Ro/SSA and anti-La/SSB Abs at presentation and one additional patient developed anti-double-stranded-DNA and anti-Sm Abs after a follow-up of more than 4 yr. No patient had anti-PM/sclerosis (Scl) nor anti-aminoacyl-tRNA synthetase Abs. All patients dramatically improved with steroids, and reached complete remission (CR) within 3 weeks. Two patients relapsed 18 months after CR. They both reached rapidly second CR using steroids associated or not with oral methotrexate. CONCLUSION: Our data suggest that anti-U1-snRNP Abs may define a subset of myositis characterized by a favourable outcome, though often associated with ILD and/or neurological manifestations.

Effectiveness of platelet transfusions after plasma exchange in adult thrombotic thrombocytopenic purpura: a report of two cases.

Plasma infusion (PI) and plasma exchange (PE) are the most efficient treatment of thrombotic thrombocytopenic purpura (TTP), allowing achievement of complete remission in 60 to 90% of cases. Life-threatening bleeding, related to severe thrombocytopenia, is one of the main complications of the disease. Thrombocytopenia may also preclude invasive procedures such as splenectomy, which may be required during the management of TTP. Platelet concentrates transfusions are usually thought to worsen the disease, especially if not associated with the appropriate treatment of this latter, and thus should be avoided. We report hereon 2 patients with TTP who experienced a surgical procedure i.e., a cholecystectomy for a cholecystitis, and a splenectomy for a refractory TTP. In both patients, the surgical procedure was preceded by a 60 mL/kg plasma exchange with solvent/detergent treated plasma as replacement fluid, followed by platelet transfusion, with a corrected count increment of 57.1% (Patient 1) and 69.3% (Patient 2). Using this sequential treatment, the patients did not experience any deterioration of their status. Both patients had a favorable outcome after surgery. However, until such a procedure will be validated on a larger series of patients, it should be restricted to patients presenting with a refractory life-threatening thrombocytopenia and/or requiring surgery or any kind of invasive procedure. Am. J. Hematol. 68:198-201, 2001. Published 2001 Wiley-Liss, Inc.

Astrovirus enteritis in a chronic lymphocytic leukemia patient treated with fludarabine monophosphate.

We report on a case of severe astrovirus gastroenteritis in a chronic lymphocytic leukemia (CLL) patient treated with fludarabine monophosphate (FAMP). Astrovirus was detected in stools using both an immunoenzymatic assay and an electronic microscopy analysis. Treatment consisted in symptomatic care and the outcome was favorable. Astrovirus infection might constitute a common etiology of gastroenteritis in patients with hematologic malignancies that have been severely immunocompromised with FAMP or other purine analogues, and therefore should be more systematically investigated.

Haemorrhagic cystitis associated with adenovirus in a patient with AIDS treated for a non-Hodgkin's lymphoma.

Adenovirus-induced haemorrhagic cystitis has been reported chiefly in bone marrow or kidney transplant recipients. We report here on an HIV-positive patient treated for a Burkitt's lymphoma who developed gross haematuria associated with fever and burning urination. Usual causes of haematuria were ruled out: lithiasis, urinary tract lesions, glomerulonephritis, mycobacterium and schistosoma infections, and drug toxicity. Adenovirus was detected by cellular cultures and BK/JC virus DNA sequences were detected using a polymerase chain reaction method. Because BK/JC virus shedding is very common (75%) in HIV patients receiving chemotherapy, our data strongly suggest that adenovirus was responsible for the haemorrhagic cystitis in our patient. In conclusion, adenovirus should be considered as a potential cause of haemorrhagic cystitis in AIDS patients whose immunosuppression is aggravated by cytotoxic drugs.

Modifications of Igalpha and Igbeta expression as a function of B lineage differentiation.

Transcription of the mb1 and B29 genes is initiated when lymphoid progenitors enter the B cell differentiation pathway, and their transmembrane Igalpha and Igbeta products constitute essential signaling components of pre-B and B cell antigen receptors. We analyzed Igalpha/Igbeta biosynthesis, heterogeneity, and molecular interactions as a function of human B lineage differentiation in cell lines representative of the pro-B, pre-B, and B cell stages. All B lineage representatives produced a 36-kDa Igbeta form and three principal Igalpha forms, transient 33/40-kDa species and a mature 44-kDa glycoprotein. Deglycosylation revealed a major Igalpha core protein of 25 kDa and a minor 21-kDa Igalpha protein, apparently the product of an alternatively spliced mRNA. In pro-B cells, the Igalpha and Igbeta molecules existed primarily in separate unassembled pools, exhibited an immature glycosylation pattern, did not associate with surrogate light chain proteins, and were retained intracellularly. Their unanticipated association with the Lyn protein-tyrosine kinase nevertheless suggests functional potential for the Igalpha/Igbeta molecules in pro-B cells. Greater heterogeneity of the Igalpha and Igbeta molecules in pre-B and B cell lines was attributable to increased glycosylation complexity. Finally, the Igalpha/Igbeta heterodimers associated with fully assembled IgM molecules as a terminal event in B cell receptor assembly.

Pulmonary infections associated with systemic capillary leak syndrome attacks in a patient with hypogammaglobulinemia.

Systemic capillary leak syndrome (SCLS) is a rare disorder of unknown etiology, characterized by recurrent hypovolemic shock attacks associated in most cases with a serum monoclonal immunoglobulin. Prophylactic therapy is usually disappointing and the outcome is often fatal. We report on a patient with recurrent hypovolemic shocks consistent with the diagnosis of SCLS associated with severe serum panhypogammaglobulinemia but no detectable monoclonal immunoglobulin or B cell proliferation. Attacks were often preceded by severe respiratory infections. Both infections and attacks were successfully prevented by i.v. gammaglobulin replacement. Further evaluation is needed to assess the efficacy of i.v. gammaglobulins in patients with SCLS but without hypogammaglobulinemia.

Severe respiratory syncytial virus pulmonary infection in a patient treated with fludarabine for chronic lymphocytic leukemia.

Fludarabine phosphate is currently proposed for the treatment of refractory chronic lymphocytic leukemia (CLL). CD4 T-lymphocyte depletion, myelosuppression, and subsequent severe infections are the major side effects of fludarabine phosphate therapy. We report here on a heretofore undescribed respiratory syncytial virus (RSV) infection in a patient with a long-standing history of refractory CLL that was treated with fludarabine phosphate. The patient developed a severe infection of the upper and lower respiratory tract with bilateral pulmonary infiltrates and severe hypoxemia. RSV was the only infectious agent that could be isolated, and treatment with aerosolized ribavirin lead to prompt improvement of all symptoms.