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Olivier Lambotte

Publications and source records attributed to Olivier Lambotte.

At least 19 recordsLinked to original sources
PubMed2024

Major depletion of insulin sensitivity-associated taxa in the gut microbiome of persons living with HIV controlled by antiretroviral drugs.

BACKGROUND: Persons living with HIV (PWH) harbor an altered gut microbiome (higher abundance of Prevotella and lower abundance of Bacillota and Ruminococcus lineages) compared to non-infected individuals. Some of these alterations are linked to sexual preference and others to the HIV infection. The relationship between these lineages and metabolic alterations, often present in aging PWH, has been poorly investigated. METHODS: In this study, we compared fecal metagenomes of 25 antiretroviral-treatment (ART)-controlled PWH to three independent control groups of 25 non-infected matched individuals by means of univariate analyses and machine learning methods. Moreover, we used two external datasets to validate predictive models of PWH classification. Next, we searched for associations between clinical and biological metabolic parameters with taxonomic and functional microbiome profiles. Finally, we compare the gut microbiome in 7 PWH after a 17-week ART switch to raltegravir/maraviroc. RESULTS: Three major enterotypes (Prevotella, Bacteroides and Ruminococcaceae) were present in all groups. The first Prevotella enterotype was enriched in PWH, with several of characteristic lineages associated with poor metabolic profiles (low HDL and adiponectin, high insulin resistance (HOMA-IR)). Conversely butyrate-producing lineages were markedly depleted in PWH independently of sexual preference and were associated with a better metabolic profile (higher HDL and adiponectin and lower HOMA-IR). Accordingly with the worst metabolic status of PWH, butyrate production and amino-acid degradation modules were associated with high HDL and adiponectin and low HOMA-IR. Random Forest models trained to classify PWH vs. control on taxonomic abundances displayed high generalization performance on two external holdout datasets (ROC AUC of 80-82%). Finally, no significant alterations in microbiome composition were observed after switching to raltegravir/maraviroc. CONCLUSION: High resolution metagenomic analyses revealed major differences in the gut microbiome of ART-controlled PWH when compared with three independent matched cohorts of controls. The observed marked insulin resistance could result both from enrichment in Prevotella lineages, and from the depletion in species producing butyrate and involved into amino-acid degradation, which depletion is linked with the HIV infection.

Humans↗
PubMed2007

The correlation between levels of IL-7Ralpha expression and responsiveness to IL-7 is lost in CD4 lymphocytes from HIV-infected patients.

Measurements of Bcl-2 and CD25 expression suggested that IL-7R function is modified in CD4 lymphocytes of untreated viraemic patients. The extent of IL-7R function restoration post-HAART was analysed. A positive linear relationship was demonstrated between IL-7Ralpha expression and the magnitude of IL-7-induced responses in healthy individuals, whereas this relationship is lost in HIV-infected patients, suggesting that viraemic patients suffer a receptor signaling transduction defect in IL-7R function. IL-7 responsiveness is only partly restored by HAART.

Anti-HIV Agents↗
PubMed2006

Decreased B cell activating factor receptor expression on peripheral lymphocytes associated with increased disease activity in primary Sjögren's syndrome and systemic lupus erythematosus.

OBJECTIVE: To analyse B cell activating factor (BAFF) receptor (BAFF-R) expression on peripheral lymphocytes from patients with primary Sjögren's syndrome (pSS) and systemic lupus erythematosus (SLE). PATIENTS AND METHODS: Peripheral blood mononuclear cells from 20 patients with pSS, 19 patients with SLE and 15 controls were examined by flow cytometry to investigate BAFF-R mean fluorescence intensity (MFI) on lymphocytes. BAFF-R mRNA level from isolated blood B cells of nine patients with pSS and eight controls was assessed by real-time quantitative reverse transcription-PCR. BAFF serum level was determined by ELISA. RESULTS: In all subjects, BAFF-R was expressed on all naïve CD27- and memory CD27+ B-cells and was present on <0.5% of T cells. The expression of BAFF-R on B cells was significantly decreased in patients with pSS as compared with controls (MFI = 7.8 vs 10.6, p = 0.001), and was intermediate in patients with SLE (MFI = 9.5). Serum BAFF level was inversely correlated with BAFF-R MFI (p = 0.007), but not because of competition between endogenous BAFF (at observed concentrations in patients) and the monoclonal antibody (11C1) detecting BAFF-R. BAFF-R mRNA levels did not differ between patients with pSS and controls (p = 0.48). BAFF-R MFI decreased after overnight culture with recombinant human BAFF (from 32.5 to 25.4, p = 0.03). Contrary to the serum BAFF level, BAFF-R expression was correlated with extraglandular involvement in pSS and SLE Disease Activity Index. CONCLUSIONS: BAFF-R expression is reduced on peripheral B cells of patients with pSS and SLE. This down-regulation occurs through a post-transcriptional mechanism and could be the consequence of chronic increase in BAFF. BAFF-R levels on B cells could be a novel activity biomarker in autoimmune diseases.

Adult↗
PubMed2006

Microbial translocation is a cause of systemic immune activation in chronic HIV infection.

Chronic activation of the immune system is a hallmark of progressive HIV infection and better predicts disease outcome than plasma viral load, yet its etiology remains obscure. Here we show that circulating microbial products, probably derived from the gastrointestinal tract, are a cause of HIV-related systemic immune activation. Circulating lipopolysaccharide, which we used as an indicator of microbial translocation, was significantly increased in chronically HIV-infected individuals and in simian immunodeficiency virus (SIV)-infected rhesus macaques (P <or= 0.002). We show that increased lipopolysaccharide is bioactive in vivo and correlates with measures of innate and adaptive immune activation. Effective antiretroviral therapy seemed to reduce microbial translocation partially. Furthermore, in nonpathogenic SIV infection of sooty mangabeys, microbial translocation did not seem to occur. These data establish a mechanism for chronic immune activation in the context of a compromised gastrointestinal mucosal surface and provide new directions for therapeutic interventions that modify the consequences of acute HIV infection.

Animals↗
PubMed2006

Characteristics and long-term outcome of 15 episodes of systemic lupus erythematosus-associated hemophagocytic syndrome.

Reactive hemophagocytic syndrome (HS) occurs mainly in the setting of serious infections and lymphomas. HS can occur in the course of 2 active systemic diseases, without simultaneous infection: adult Still disease and systemic lupus erythematosus (SLE). Observations of specific lupus-associated HS are rare, and the long-term outcome of these patients with active SLE is unknown. We retrospectively studied 15 episodes of SLE-associated HS in 12 patients (10 women, 2 men) and noted the long-term outcome. HS occurred at a mean age of 25 years. All patients were febrile with >or=2 cytopenias, and bone marrow aspiration indicated hemophagocytosis. HS revealed SLE in 9 patients and recurred in 3. The main features of SLE-associated HS were a low frequency of hepatosplenomegaly, a high frequency of heart involvement (5 pericarditis, 4 myocarditis requiring transfer to intensive care unit), and a low C-reactive protein level (mean, 15 mg/L). Cutaneous-mucous symptoms of SLE, arthritis, and nephritis were present respectively in 8 (53%), 6 (40%), and 4 (27%) episodes, but symptoms of SLE were absent in 4 episodes at admission. All patients had anti-nuclear antibodies when the HS occurred. Anti-double-stranded DNA antibodies were present in 12 episodes. Treatment was steroids in 14 cases but cyclophosphamide was the only treatment able to control HS in 2 cases. All the cases of SLE-associated HS were controlled by the immunosuppressive regimen. Intravenous immunoglobulins seemed poorly effective. No infectious agent was found. Clinical presentations of the 23 patients with SLE-associated HS described in the literature were reviewed and were similar to those of the current series. The mean follow-up was 88 months (range, 7-240 mo). One patient died at 15 months (sepsis). Among the 5 patients with a follow-up >8 years, 4 always had active disease. During the follow-up of SLE, immunosuppressive drugs were added in 8 patients (cyclophosphamide in 7, azathioprine in 3, mycophenolate mofetil in 2) with significant adverse drug reactions. In the long-term, SLE-associated HS seems to define a severe SLE form with frequent flares, possible HS recurrences, and the need for prolonged immunosuppression.

Adolescent↗
PubMed2006

Regulatory dysfunction of the interleukin-7 receptor in CD4 and CD8 lymphocytes from HIV-infected patients--effects of antiretroviral therapy.

Despite an increase in plasma IL-7 levels, the CD4 T-cell pool decrease progressively in HIV-infected patients. Here we report on our tests to check the hypothesis that defects in the IL-7 receptor system might be involved in this phenomenon. The cell surface expression of CD127 was measured ex vivo in CD4 and CD8 T lymphocytes drawn from 3 groups of HIV patients. IL-7 function was also followed in vitro by measuring IL-7-driven T-cell proliferation, the induction of the CD25 activation marker, and overexpression of the antiapoptotic molecule Bcl-2. Untreated viremic patients showed a slight but significant decrease in CD127 expression on the surface of their CD4 lymphocytes. By contrast, CD127 expression was substantially altered on the surface of CD8 T lymphocytes taken from untreated viremic patients. IL-7-induced overexpression of the antiapoptotic molecule Bcl-2 was dramatically altered in viremic patients, whereas IL-7-dependent CD25 induction and T-cell proliferation were reduced. Highly active antiretroviral therapy partially corrected these defects in patients with an undetectable viral load and CD4 counts of more than 400 cells/microL. The effects of HAART were less pronounced in patients with undetectable VL but low CD4 counts (<250 cells/microL). The IL-7 receptor is dysfunctional in the CD4 and CD8 lymphocytes of HIV-infected patients. This may be due to abnormal activation of the immune system in HIV-infected patients and may contribute to the reduced CD4 count and the altered function of the CD8 compartment.

Antiretroviral Therapy, Highly Active↗
PubMed2005

HIV controllers: a homogeneous group of HIV-1-infected patients with spontaneous control of viral replication.

We identified a total 15 patients who have maintained undetectable plasma HIV RNA loads without antiretroviral treatment for >10 years from cohorts of 1300 and 1551 patients infected with human immunodeficiency virus (HIV). These 15 patients, whom we have referred to as "HIV controllers," are characterized by a low HIV DNA load in peripheral blood mononuclear cells and by a strong HIV-specific immune response.

Adult↗
PubMed2005

Efficacy of mycophenolate mofetil in adult refractory auto-immune cytopenias: a single center preliminary study.

UNLABELLED: Treatment of auto-immune cytopenia refractory to front line therapy with intravenous immunoglobulins and steroids is a matter of concern. We assessed the efficacy and safety of mycophenolate mofetil in a prospective open preliminary study. STUDY DESIGN: Adult patients with steroid refractory auto-immune cytopenias were included. Mycophenolate mofetil (MMF) was added to treatment given at the time of inclusion, and efficacy was evaluated in term of improvement of platelet/haemoglobin levels and in term of reduction of previously given drugs, if any. All auto-immune thrombocytopenic purpura (AITP) patients had serologic assessment for associated auto-antibodies at the time of inclusion. Cytopenias associated with other auto-immune diseases, lymphoproliferative diseases or HIV infection were excluded. RESULTS: From November 1999 through November 2003, 13 patients were included (nine AITP, three auto-immune haemolytic anaemia (AIHA), one Evans' syndrome; four males, nine females; age: 35-72 yr). For AITP patients, an overall response of 78% was observed. Retrospective analysis showed no significant difference between patients having a short disease duration (<1 yr) and longer disease duration; between patients who previously received more or less than three treatments; and between patients for whom MMF was started as monotherapy or in association with prednisone, However, all AITP patients presenting associated auto-antibodies responded to MMF, while only 50% of patients without associated antibodies were responders. All patients presenting AIHA and Evans' syndrome were responders. The drug was well tolerated, with no significant side effects reported. The cumulative data suggest a potential place for MMF in the treatment arsenal of refractory cytopenias.

Adult↗
PubMed2005

Efficacy of rituximab in refractory polymyositis.

We describe the effectiveness of rituximab, an anti-B lymphocyte monoclonal antibody, in a case of refractory polymyositis with interstitial pulmonary disease and anti-Jo-1 autoantibody (antisynthetase syndrome). Rituximab was well tolerated, and its efficacy in inflammatory myositis should be evaluated.

Antibodies, Antinuclear↗
PubMed2005

Anti-retroviral therapy in HIV-infected patients: in vitro effects of AZT and saquinavir on the response of CD4 and CD8 lymphocytes to interleukin-7.

IL-7 is a crucial cytokine regulating lymphopoiesis and peripheral T lymphocyte homeostasis. Plasma IL-7 levels increase during HIV infection and, although antiretroviral therapy (ARV therapy) decreases these levels, they fail to return to normal. Immune reconstitution in most ARV-treated patients is only partial. We tested the possibility that the IL-7R system might be affected by ARV drugs. The effects of the antireverse transcriptase AZT and the anti-protease saquinavir on CD3- and CD3+CD28-induced T lymphocyte stimulation, in the presence (or absence) of IL-7, were studied in vitro. Small amounts of the drugs did not interfere with the capacity of IL-7 to stimulate T cell proliferation, but higher concentrations significantly decreased IL-7-induced T cell proliferation both in cells from HIV-infected patients and in cells from healthy donors. IL-7 is known to down-modulate its own receptor on the surface of CD4 and CD8 T lymphocytes in vitro. In CD4 lymphocytes from healthy donors or HIV-infected patients, neither AZT, nor saquinavir, nor a combination of the two, interfered with this property. In contrast, AZT + saquinavir worsened the IL-7-induced down-regulation of CD127 expression by CD8 T cells from HIV-infected patients, while no such effect was observed with CD8 T cells from healthy donors. Our data suggest that, under certain conditions, antiretroviral therapy could interfere with the expression and function of the IL-7/IL-7R system, and more particularly it may affect the CD8-lymphocyte compartment of HIV-infected patients.

Adult↗
PubMed2004

Pegylated interferon alpha-2a-associated life-threatening Evans' syndrome in a patient with chronic hepatitis C.

In this report, we describe an unusual and unreported complication with the new licensed form of pegylated interferon alpha2a (PEG-IFN-alpha2a). We report the first case of severe autoimmune cytopenias, an Evans' syndrome, in a patient with chronic hepatitis C, 2 months after PEG-IFN-alpha2a initiation. Haemolytic anaemia and thrombocytopenia developed, complicated by gastric bleeding and brain haemorrhage. Outcome was favourable under immunosuppressive treatment. Treatment with PEG-IFN-alpha2a requires careful follow-up, as IFNalpha can induce or exacerbate autoimmune diseases.

Aged↗
PubMed2004

The lymphocyte HIV reservoir in patients on long-term HAART is a memory of virus evolution.

OBJECTIVE: To investigate the dynamics of the lymphocyte HIV reservoir in patients on prolonged and effective highly active antiretroviral therapy (HAART). DESIGN: Nine HAART-treated patients were selected on the basis of long-term infection and long-term undetectable plasma viral RNA. Five patients had received antiretroviral therapy before HAART. We compared a polymorphic region of the env gene (C2V4), and the part of the pol gene encoding the reverse transcriptase in pre-HAART plasma and in the reservoir lymphocytes during HAART; the first plasma sample taken after structured treatment interruption was also studied in three patients. METHODS: Both regions of interest were amplified from plasma HIV RNA and cellular proviral DNA, then cloned, sequenced and subjected to phylogenetic analysis. RESULTS: Diversity of the lymphocyte reservoir was found in six of nine patients. Archiving of pre-HAART plasma clones was observed in six of nine patients. 'Wild-type' and zidovudine-resistant strains co-existed in reservoir T cells of two pre-HAART treated patients. In three patients, no resistant virus was found in the T-cell reservoir despite the detection of resistant virus in pre-HAART plasmas. However, virus archiving was documented in two of these three patients on the basis of C2V4 analysis. Latently infected T cells only partly accounted for the plasma viral load rebound after structured treatment interruption. CONCLUSIONS: The HIV lymphocyte reservoir is dynamic. Its diversity results mainly from successive archiving of circulating plasma viruses during the course of HIV infection. Archiving of resistant virus must be taken into account in therapeutic decisions.

Antiretroviral Therapy, Highly Active↗
PubMed2004

Hemophagocytic syndrome as a presenting sign of transformation of smoldering to acute adult T-cell leukemia/lymphoma: efficacy of anti-retroviral and interferon therapy.

A 55-year-old Caribbean woman with a 6-year history of smoldering adult T-cell leukemia/lymphoma presented with clinical and biological symptoms of hemophagocytic syndrome. An extensive search for infectious diseases was negative. A lymph node biopsy showing large T-cell lymphoma (CD4-, CD25+) and findings of high LDH count and severe lymphocytosis led to the diagnosis of acute adult T-cell leukemia/lymphoma. Anti-retroviral therapy combining zidovudine, lamivudine, and interferon-alpha was started, resulting in rapid control of both hemophagocytic syndrome and symptoms of acute adult T-cell leukemia/lymphoma. Thus, we propose that adult T-cell leukemia/lymphoma must be added to the spectrum of etiologies of hemophagocytic syndrome.

Antineoplastic Agents↗
PubMed2003

Multiple myeloma presenting as fever of unknown origin.

BACKGROUND: Multiple myeloma (MM) itself is not considered to be responsible for fever and is not usually listed among the causes of fever of unknown origin (FUO). METHODS: We report three cases of MM presenting with specific fever that we analyze in combination with the three previously published cases. RESULTS: MM could easily be suspected in most, but not all, cases, emphasizing that bone marrow aspiration should be a part of 'standard' FUO investigations. All patients underwent extensive, sometimes potentially harmful, investigations. Conventional treatment of MM produced a sustained improvement in the temperature curve and inflammatory syndrome in all cases within a few months. Fever recurred during nearly all relapses. Six patients died, one after a disease course of more than 8 years. CONCLUSIONS: This series shows that MM may present as a FUO and that useless and hazardous investigations may be avoided given the possibility of specific fever in this disease. Chemotherapy must be considered without much delay after a reasonable work-up to eliminate any associated process, especially infections.

Journal Article↗
PubMed2003

HIV-1 persistence, viral reservoir, and the central nervous system in the HAART era.

HAART therapy has led to a significant reduction of general and neurological morbidity, and mortality among HIV-1 infected patients. It can also decrease HIV-1 RNA titres in plasma and CSF towards undetectable level. However, the initial hope of achieving total eradication of the virus from the body has vanished. Even in patients who do not develop viral resistance or treatment intolerance, two kinds of viral persistence have been demonstrated both in lymphoid and central nervous system. The first one is a smoldering infection that persists, despite prolonged and apparently efficient HAART, in monocytes, tissue macrophages and most probably microglia. The second one is an integration of proviral DNA in the genome of subpopulations of CD4 lymphocytes of patients receiving efficient HAART. A similar viral integration in astrocytes and less likely in resting microglia is suggested by several studies, although it has yet to be demonstrated conclusively.

Antiretroviral Therapy, Highly Active↗
PubMed2003

High ferritin and low glycosylated ferritin may also be a marker of excessive macrophage activation.

OBJECTIVE: A high serum ferritin concentration with a low percentage of glycosylated ferritin (< 20%) have been reported to be a specific marker of active adult Still's disease (ASD). However, high ferritin levels are found during hemophagocytosis syndrome (HS). We investigated the ferritin level and the percentage of glycosylation in a HS series of various causes. METHODS: Diagnosis of HS was confirmed by erythrophagocytosis pictures on a bone marrow cytology or biopsy in all patients. Serum ferritin concentration was determined on a heterogenous immunoassay module. Glycosylated ferritin was separated using concanavalin A (Con-A) sepharose 4B chromatography. The nonglycosylated ferritin unbound to Con-A was recovered in the supernatant and quantified with the same procedure. Percentages of glycosylated ferritin less than 20% are considered to be usual in ASD, between 20 and 40% usual in inflammatory syndrome, and between 50 and 80% normal. RESULTS: In all cases tested during the acute phase of the disease, ferritin blood level was high and the percentage of glycosylated ferritin was low, less than 20%. CONCLUSION: The combination of high ferritin level and low percentage of glycosylation may be a marker of excessive macrophage activation.

Adult↗
PubMed2002

Persistence of replication-competent HIV in both memory and naive CD4 T cell subsets in patients on prolonged and effective HAART.

OBJECTIVE: To investigate the phenotypic features of infected lymphocytes in patients on prolonged and effective highly active antiretroviral therapy (HAART). DESIGN: We examined highly purified subsets of memory and naive CD4 T lymphocytes for the presence of replication-competent virus. METHODS: In 11 highly selected HAART-treated patients, we isolated highly purified CD45RO CD45RA CD4 T cells using a magnetic bead-based procedure. In some patients, a subsequent cell separation according to CD62L expression was performed. We quantified total viral DNA in freshly isolated T-cell subsets. To verify whether the virus was replication-competent, HIV RNA was measured in supernatants following cell activation. RESULTS: HIV DNA was detectable in the CD45RO and CD45RA CD4 T-cell subsets in 100% and 90% of the patients tested, respectively. In central memory CD45ROCD62L, effector memory CD45RO+CD62L-, truly naive CD45RACD62L, and CD45RA+CD62L- CD4 T cells, HIV DNA was found in 100%, 55%, 88%, and 50% of the patients tested respectively. HIV DNA was significantly higher in the CD45RO fraction than in the CD45RA subset and in the CD45ROCD62L fraction than in the three other CD45RA/ROCD62L+/- subsets. Detectable HIV RNA was found in the culture supernatants of CD45RO and CD45RA CD4 T-cell subsets in 80% and 66% of the patients tested respectively, and in CD45ROCD62L, CD45RO+CD62L-, CD45RACD62L, and CD45RA+CD62L- CD4 T cells in 100%, 100%, 100% and 50% of the patients tested respectively. CONCLUSIONS: In patients on prolonged and effective HAART, the pool of infected CD4 T lymphocytes consists predominantly of memory cells but also contains naive cells.

Antiretroviral Therapy, Highly Active↗