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A S Korganow

Publications and source records attributed to A S Korganow.

16 recordsLinked to original sources
PubMed2002

[Pulmonary histiocytosis, then bronchiolo-alveolar cancer in HIV-1 infection].

INTRODUCTION: Langerhans cell pulmonary histiocytosis is a rare disease, primarily enhanced by smoking, and of unclear mechanism. OBSERVATION: A 42 year-old man, smoking 25 packs-years, was infected by a type 1 human immunodeficiency virus (HIV-1). He successively developed pulmonary emphysema, Langerhans cell pulmonary histiocytosis and alveolar bronchial carcinoma of the lower right pulmonary lobe, which was fatal. DISCUSSION: We discuss the concomitance of pulmonary histiocytosis and alveolar bronchial carcinoma, exceptional in the literature, and the eventual enhancing role of HIV-1 infection. The principal incriminating factor in pulmonary histiocytosis probably remains smoking, but the HIV-1 infection may have participated in the emergence of the neoplastic pathology.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed2002

Expansion of marginal zone B cells is not sufficient for the development of renal disease in NZBxNZW F1 mice.

The mechanisms which govern the production of autoantibodies and of tissue damage during systemic lupus (SLE) are still unclear. In the NZBxNZW F1 (BW) model of SLE glomerulonephritis, the activation and commitment of B cells are thought to play a major role in disease progression. Previous analysis has suggested that these mice have a substantial increase of marginal zone (MZ) B cells before the occurrence of the disease. Owing to the probable role of this B cell subset in autoantibody production, it was important to define the possible link between this abnormality and the occurrence of kidney damage. Using cytofluorometry analysis, we followed the splenic MZ B cell phenotype in different series of mice with shared autoimmune genetic background and histologically defined renal status. By comparing BW females and BW males, NZB and NZW mice, we confirm that BW mice have an increase in MZ B cells but this MZ B cells expansion is not directly linked to tissue lesions. Genetically modified BW female mice with a restricted repertoire of B and T cell antigen receptors, and which do not develop nephritis, exhibit the same increase of MZ B cells, suggesting that this increase does not depend on a specific set of antigens. Moreover, our analysis brings to light a pre-disease state in BW males, with autoantibody production and mesangial deposits.

Animals↗
PubMed2000

Salivary gland lymphomas in patients with Sjögren's syndrome may frequently develop from rheumatoid factor B cells.

OBJECTIVE: Patients with Sjögren's syndrome (SS) have an increased risk of developing monoclonal B cell non-Hodgkin's lymphomas (MNHL), which frequently occur in the salivary glands (SG). The transition from the benign lymphocyte infiltrate of the gland that characterizes SS to MNHL is not well understood. Previous sequence analyses of the expressed variable (V) region genes have supported the theory that the surface Ig (sIg) plays an important role in the initial expansion of nonmalignant B cell clones and in lymphomagenesis. However, the antigenic specificities of these B cells were unknown. We describe the specificities of the Ig expressed by 2 cases of MNHL that developed in the SG of 2 patients with SS. METHODS: The expressed V genes were amplified by polymerase chain reaction from biopsy specimens, sequenced, and subcloned into eukaryotic expression vectors. The constructs were transfected into P3X63-Ag8.653 cells to obtain 2 monoclonal cell lines, each secreting 1 of the sIg expressed by the MNHL. These IgM were tested by enzyme-linked immunosorbent assay and immunofluorescence against a panel of antigens potentially implicated in SS. RESULTS: Our main finding was that the Ig products of the neoplastic B cells were rheumatoid factors (RF). Contrary to expectations, they did not react with nuclear or cytoplasmic antigens, double-stranded DNA, self antigens commonly bound by natural autoantibodies, or SG tissue. CONCLUSION: Previous analyses of V gene use have provided indirect evidence that SG MNHL may frequently express RF. We demonstrate that this hypothesis is true in the 2 patients we studied. Large-scale studies will be needed to establish the exact frequency of RF specificity among SS-associated MNHL.

Aged↗
PubMed1999

The arthritogenic T cell receptor and its ligand in a model of spontaneous arthritis.

OBJECTIVE: Spontaneous arthritis in the KRN transgenic mouse model is due to the autoreactivity of the transgenic T cell receptor (TCR) against Ag7 major histocompatibility complex (MHC) molecules, which leads to strong but incomplete clonal deletion. We sought to determine whether other stimuli triggering this receptor might provoke arthritis, whether the apparently systemic reactivity might have some joint-preferential component explaining the paradoxical arthritic phenotype, and whether the transgenic receptor was the only one required or whether other TCRs might be ferried along in a leaky tolerance process. METHODS: Crosses and radiation chimeras involving a panel of transgenic and knockout mouse lines were used. The reactivity of the KRN TCR was tested in carboxyfluorescein diacetate succinimidyl ester-transfer experiments and in crosses with transgenic or inbred mice expressing other molecules that stimulate the KRN receptor (the mls-1a superantigen, the Aalpha(k69)Abeta(k) mutant MHC molecule). The arthritogenic capacity of T cells expressing only the KRN TCR was tested by crossing to recombination-activating gene-knockout mice, and constructing bone marrow chimeras with precursors to these strictly monoclonal T cells. RESULTS: The data show that the KRN TCR itself is the only receptor needed. It needs to be triggered by the Ag7 molecule loaded with self-peptides in order to provoke arthritis, but there is no indication of preferential presentation of joint-derived peptides. CONCLUSION: Arthritis can be generated by systemic recognition of self-MHC-peptide complexes by autoreactive T cells. This triggers B lymphocytes to produce arthritogenic antibodies, without the involvement of joint-specific T cell targets.

Animals↗
PubMed1999

From systemic T cell self-reactivity to organ-specific autoimmune disease via immunoglobulins.

Rheumatoid arthritis is a common and debilitating autoimmune disease whose cause and mechanism remain a mystery. We recently described a T cell receptor transgenic mouse model that spontaneously develops a disease with most of the clinical, histological, and immunological features of rheumatoid arthritis in humans. Disease development in K/BxN mice is initiated by systemic T cell self-reactivity; it requires T cells, as expected, but B cells are also needed, more surprisingly. Here, we have identified the role of B cells as the secretion of arthritogenic immunoglobulins. We suggest that a similar scenario may unfold in some other arthritis models and in human patients, beginning with pervasive T cell autoreactivity and ending in immunoglobulin-provoked joint destruction.

Adoptive Transfer↗
PubMed1999

Different modes of pathogenesis in T-cell-dependent autoimmunity: clues from two TCR transgenic systems.

T lymphocytes constantly flirt with reactivity to self peptides, a price they pay for their ability to recognize foreign peptides presented by self-MHC molecules, and autoreactivity in the T compartment occasionally gives rise to autoimmune disease. Pathology from T-cell autoimmunity can manifest itself through radically different strategies, as we have observed recently in two transgenic models. In the BDC2.5 diabetes model, T cells express a transgene-encoded T-cell receptor (TCR) with reactivity against a pancreatic antigen. This leads to a massive, if often controlled, infiltration of the pancreatic islets. Target cell destruction then results from the local consequences of this local immune/inflammatory process. On the other hand, the arthritic manifestations of the KRN transgenic model are indirect: the transgenic TCR confers a broad autoreactivity, through which T cells stimulate B cells to produce arthritogenic immunoglobulins. These molecules are then sufficient to produce the disease, even in the complete absence of any lymphocytes. Although important questions subsist in this model--how the KRN T cells interfere with B-cell tolerance, what the target of arthritogenic IgG is--its implication is that an isolated T-cell dysregulation may manifest itself through an Ig-mediated disease.

Animals↗
PubMed1998

[Soluble tumor necrosis factor receptors in patients with systemic lupus erythematosus].

OBJECTIVE: To study the variations of type II soluble receptors for tumor necrosis factor (sR-TNF) in patients with systemic lupus erythematosus and investigate their use in the clinical setting. PATIENTS AND METHODS: Twenty-six patients with systemic lupus were followed for a mean 3 years. sR-TNF and other immunological parameters (C reactive protein, anti-DNA antibodies, C3 and C4 complement fractions, soluble receptors for interleukin 2) were measured in sera at different points of the disease course. The systemic lupus activity measure (SLAM) was determined at each point, and confronted with the biology results. The study was cross sectional for the group and longitudinal for the patients. RESULTS: sR-TNF was the immunological parameter which correlated best with SLAM. It also correlated with sedimentation rate, C reactive protein, thrombopenia, anemia, creatinine level, anti-DNA antibodies and sR-IL2. The longitudinal study pointed out however that this finding is not consistent for each patient. CONCLUSION: A rise in sR-TNF related to systemic lupus activity but is of limited practical interest for individual patient follow-up.

C-Reactive Protein↗
PubMed1998

[Humoral immunity].

Explore the source record for details and available documents.

Antibody Formation↗
PubMed1997

[Lipomatosis induced by corticosteroid therapy].

Steroid-induced lipomatosis usually presents as a localized hypertrophy of the adipose tissue and seems more common than previously thought. Most patients develop this phenomenon after prolonged administration of moderate to high doses of oral corticosteroids. The localizations are numerous and determine the clinical presentation. Often asymptomatic, they can also be revealed by worrying symptoms usually due to a compressive syndrome. The most frequently reported localizations (spinal epidural, retro-orbital, mediastinal) are also the most clinically apparent. The cessation or reduction of steroid therapy, when medically possible, inconsistently results in the decrease or disappearance of the lipomatosis deposits. Computerized tomography or magnetic resonance imaging are the most helpful diagnostic means. Interestingly, these lipomatoses have rarely been reported in patients with Cushing disease. Their pathophysiology remains poorly elucidated and may imply an inhibition of the brown adipose tissue lipolysis.

Adult↗
PubMed1996

Organ-specific disease provoked by systemic autoimmunity.

Rheumatoid arthritis (RA) is a chronic joint disease characterized by leukocyte invasion and synoviocyte activation followed by cartilage and bone destruction. Its etiology and pathogenesis are poorly understood. We describe a spontaneous mouse model of this syndrome, generated fortuitously by crossing a T cell receptor (TCR) transgenic line with the NOD strain. All offspring develop a joint disease highly reminiscent of RA in man. The trigger for the murine disorder is chance recognition of a NOD-derived major histocompatibility complex (MHC) class II molecule by the transgenic TCR; progression to arthritis involves CD4+ T, B, and probably myeloid cells. Thus, a joint-specific disease need not arise from response to a joint-specific antigen but can be precipitated by a breakdown in general mechanisms of self-tolerance resulting in systemic self-reactivity. We suggest that human RA develops by an analogous mechanism.

Alleles↗
PubMed1994

Molecular analysis of rearranged VH genes during B cell chronic lymphocytic leukemia: intraclonal stability is frequent but not constant.

Several genetic mechanisms have been shown to diversify the expressed antibody repertoire of committed B lymphocytes. These include V gene replacement, ongoing gene rearrangement and somatic hypermutation. These mechanisms may be operational at discrete points in the B cell differentiation pathway and generate idiotype diversity in various malignant B cell tumors. In particular, V region mutations have been established as a major mechanism of tumor escape from anti-idiotype immunotherapy in some lymphoma. On the other hand, previous studies on a few selected cases have shown that this mutation process does not affect the B cell clone during chronic lymphocytic leukemia. However, to what extent this intraclonal stability is a general phenomenon during B cell CLL is not clear. Therefore, we randomly selected 6 patients suffering from classical B cell CLL (sIgM (+), CD5 (+), CD19 (+)) at different stages of the disease and analysed the intraclonal variability of the expressed variable region of the heavy chain (VH). After PCR amplification of the cDNA corresponding to the rearranged VDJ regions, the products were cloned and sequenced. In five cases, multiple clone analysis did not show any intraclonal variability whatever the stage of the disease. Furthermore, in a single case, this intraclonal stability was confirmed during a three year period of time when the disease progressed. The sixth case behaved differently since we found multiple nucleotide substitutions, apparently accumulating as the malignant clone expanded. Besides the theoretical difficulties that these changes can induce during immunotherapy, two findings merit further discussion: 1) the distribution of the ongoing mutations affecting the VH region was not suggestive of an antigen driven selection, 2) this intraclonal variability was specific for the VH region, since the VL region showed no intraclonal variation.

Aged↗
PubMedDate not supplied

[Rhabdomyolysis caused by simvastatinin a patient following heart transplantation and cyclosporine therapy].

Hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are cholesterol-lowering agents which may induce rhabdomyolysis. The authors present a case of rhabdomyolysis attributed to simvastatin in a heart-transplant recipient. They stress the probability of a dose-dependent muscular toxicity and the risk of overdosage in patients already under treatment with drugs that interfere with the pharmacokinetics of HMG-CoA reductase inhibitors, notably ciclosporine.

Anticholesteremic Agents↗