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.

Fate of surrogate light chains in B lineage cells.

Biosynthesis of the immunoglobulin (Ig) receptor components and their assembly were examined in cell lines representative of early stages in human B lineage development. In pro-B cells, the nascent surrogate light chain proteins form a complex that transiently associates in the endoplasmic reticulum with a spectrum of unidentified proteins (40, 60, and 98 kD) and Bip, a heat shock protein family member. Lacking companion heavy chains, the surrogate light chains in pro-B cells do not associate with either the Ig(alpha) or Ig(beta) signal transduction units, undergo rapid degradation, and fail to reach the pro-B cell surface. In pre-B cells, by contrast, a significant portion of the surrogate light chain proteins associate with mu heavy chains, Ig(alpha), and Ig(beta) to form a stable receptor complex with a relatively long half-life. Early in this assembly process, Bip/GRP78, calnexin, GRP94, and a protein of approximately 17 kD differentially bind to the nascent mu heavy chains. The 17-kD intermediate is gradually replaced by the surrogate light chain protein complex, and the Ig(alpha) and Ig(beta) chains bind progressively to the mu heavy chains during the complex and relatively inefficient process of pre-B receptor assembly. The results suggest that, in humans, heavy chain association is essential for surrogate light chain survival and transport to the cell surface as an integral receptor component.

Identification and characterization of autoantibodies against the nuclear envelope lamin B receptor from patients with primary biliary cirrhosis.

We have identified autoantibodies from two patients with primary biliary cirrhosis (PBC) that recognize the nuclear envelope of mammalian cells on indirect immunofluorescence microscopy. These antibodies bind to a 58-kD integral membrane protein (p58) of the turkey erythrocyte nuclear envelope, which has been previously identified as a membrane receptor for lamin B (Worman, H. J., J. Yuan, G. Blobel, and S. D. Georgatos. 1988. Proc. Natl. Acad. Sci. USA. 85:8531). The antibodies also bind to a 61-kD integral membrane protein (p61) of the rat liver nuclear envelope. Affinity-purified antibodies eluted from turkey p58 bind to rat p61, showing that the two proteins share an epitope(s) and that p61 is likely the rat liver lamin B receptor. In human nuclear envelopes, the antigen recognized has an apparent molecular mass close to that of avian protein. These findings, along with the previous discovery of autoantibodies against an integral membrane glycoprotein (gp210) of the nuclear pore membrane in patients with PBC, suggest that antibodies against integral membrane proteins of the nuclear envelope are characteristic of a subset of patients with PBC.

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.

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.

The 210-kD nuclear envelope polypeptide recognized by human autoantibodies in primary biliary cirrhosis is the major glycoprotein of the nuclear pore.

We have recently reported a new family of nuclear autoantibodies in a subset of patients with primary biliary cirrhosis. These antibodies bind to a nuclear envelope polypeptide(s) of approximately 200 kD, the exact identity of which was not established. In this study, we show that all of these autoantibodies are directed against a 210-kD integral membrane glycoprotein of the nuclear pore.

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.

AIDS-associated Kaposi's sarcoma in female patients.

Kaposi's sarcoma (KS) is very unusual in Caucasian women with AIDS. We conducted a retrospective survey of 12 female AIDS patients with KS, including 11 Caucasian women. HIV infection was thought to have been acquired after sexual contact, intravenous drug use (nine cases) or blood transfusion (three cases). In these patients KS was often the first manifestation of AIDS and showed an aggressive course. The disease was associated with a severe immunodeficiency (CD4 T lymphocyte count less than 100 x 10(6)/l in 50% of cases) and a poor prognosis. In four patients, lesions first developed on areas of sexual contact, supporting the hypothesis that KS is a sexually transmitted disease.

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.

[Primary biliary cirrhosis: current modes of presentation. Clinical, biochemical, immunologic and histologic study of 206 patients seen from 1978 to 1988]. / La cirrhose biliaire primitive: modes actuels de présentation. Etude clinique, biochimique, immunologique et histologique de 206 malades observés de 1978 à 1988.

The aim of this study, based on a series of 206 patients (186 women and 20 men) with primary biliary cirrhosis seen from 1978 to 1988, was to assess the current modes of presentation of the disease. In approximately 30 percent of patients, primary biliary cirrhosis was recognized at an asymptomatic stage. Two thirds of these patients remained asymptomatic: they were older (mean age 57 years) and had less severe histological lesions than the patients who became symptomatic (mean age 45 years). The modes of presentation were not markedly different in the male and female patients of our series. The prevalence of cholelithiasis seemed to be particularly high (more than 20 percent in our patients). Complications of portal hypertension (bleeding esophageal varices or ascites) were the initial manifestations of primary biliary cirrhosis in 8 percent of our symptomatic patients. Alkaline phosphatase level was normal or only slightly increased in 15 percent of our patients: a normal level or a slight increase in alkaline phosphatases is not an argument against the diagnosis of primary biliary cirrhosis. Antinuclear antibodies with perinuclear fluorescence were demonstrated in 26 percent of our patients; in most of these patients, an antibody to a 200 kD protein of the nuclear envelope was present; in patients with this antibody, asthenia, arthralgias and associated extrahepatic diseases were less common and the titers of antibodies to mitochondria were lower than in the patients without this antibody.

[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.

[Treatment of severe staphylococcal infections. Failure of rifampicin in combination therapy. 4 cases]. / Traitement des staphylococcies graves. Echecs de la rifampicine en association. Quatre observations.

Seven patients with severe methicillin-resistant Staphylococcus aureus infections (5 with bacterial endocarditis, 1 with mediastinitis and 1 with meningitis and septicaemia) were treated with rifampicin combined with vancomycin in 6 cases and with gentamicin in 1 case. The 7 strains initially isolated from haemocultures were resistant to methicillin and sensitive to rifampicin. In 4 of these patients (3 of whom received vancomycin and 1 gentamicin) clinical and bacteriological failure was observed, with selection of rifampicin-resistant mutants. Bactericidal activity was always mediocre in both serum and cerebrospinal fluid, with insufficient vancomycin and gentamicin concentrations in 3 patients. An in vitro study of the combined antibiotics by the chequer-board method suggested antagonism in 3 of these 4 cases. Thus, in spite of its excellent activity and unquestionable effectiveness, rifampicin should be used with caution in severe staphylococcal infections.

[Analysis of expression of the molecules Igalpha and Igbeta in human pro-B leukemic lines]. / Analyse de l'expression des molécules Ig alpha et Ig beta dans les lignées leucémiques pro-B humaines.

Ig alpha and Ig beta are two glycosylated transmembrane proteins of the Ig superfamily that are encoded by the B cell-specific genes mb-1 and B29, respectively. Ig alpha/Ig beta heterodimers may associate with the mu/surrogate light chains (psi LC) complex and with membrane Immunoglobulins on the surface of pre-B and B cells, respectively. They play a crucial role in the signal transduction that follows pre-B and B cell receptor cross-linking. Previous works have shown that mb-1 and B29 transcripts are expressed in normal mouse and human pro-B cells. However, little is known about the expression of Ig alpha and Ig beta molecules in pro-B cells. To address this issue we first analysed the expression of the Ig alpha and Ig beta molecules in the RS4; 11 and Nalm16 human pro-B cell lines using specific monoclonal antibodies. We found that both cell lines expressed Ig alpha and Ig beta but this expression was limited to the cytoplasm compartment. Three forms (44, 40 and 36 kDa) of the Ig alpha molecule and a single form (36 kDa) of the Ig beta molecule were detected in these lines. The heterogeneity of the Ig alpha molecule was partly related to the presence of a truncated Ig alpha protein which is likely the product of a short mb-1 transcript expressed in these cell lines. This short transcript is generated by alternative splicing of the mb1 mRNA with loss of exon 2. Ig alpha heterogeneity was also related to the expression of different glycosylated forms of the Ig alpha molecule. Only a minor fraction of the Ig alpha and Ig beta molecules associate with each other to form Ig alpha/Ig beta heterodimers and Ig beta homodimers. In these pro-B cell lines Ig alpha and Ig beta were found to associate with the lyn tyrosine kinase, suggesting that they may play some functional role at this B cell differentiation stage. Transfection of muHC gene in the Nalm16 cells results in the assembly of the pre-B receptor and in its expression on the cell surface. The level of surface expression of the pre-B receptor was found to correlate with the level of muHC and psi LC synthesis and with the level of association of the different components of the pre-B receptor with each other. Analysis of the 697 and Nalm6 pre-B cells and of the Ramos B cells indicated that heterogeneity of Ig alpha and Ig beta increases as a function of B cell differentiation.

[Bronchial complications of primary humoral immunodeficiency]. / Complications bronchiques des déficits primitifs de l'immunité humorale.

Primary humoral immunodeficiency is characterized by an abnormal immunoglobulin production. More than twelve forms are now known and a reviewed by the authors. The deficiency is responsible for bronchial infections which in the long term may result in bronchiectasis. It may also result in benign follicular hyperplasia. The specific treatment is substitutive and not devoid of hazards.

[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.