Exhausted Cytotoxic Control of Epstein-Barr Virus in Human Lupus

Systemic Lupus Erythematosus (SLE) pathology has long been associated with an increased Epstein-Barr Virus (EBV) seropositivity, viremia and cross-reactive serum antibodies specific for both virus and self. It has therefore been postulated that EBV triggers SLE immunopathology, although the mechanism remains elusive. Here, we investigate whether frequent peaks of EBV viral load in SLE patients are a consequence of dysfunctional anti-EBV CD8+ T cell responses. Both inactive and active SLE patients (n = 76 and 42, respectively), have significantly elevated EBV viral loads (P = 0.003 and 0.002, respectively) compared to age- and sex-matched healthy controls (n = 29). Interestingly, less EBV-specific CD8+ T cells are able to secrete multiple cytokines (IFN-γ, TNF-α, IL-2 and MIP-1β) in inactive and active SLE patients compared to controls (P = 0.0003 and 0.0084, respectively). Moreover, EBV-specific CD8+ T cells are also less cytotoxic in SLE patients than in controls (CD107a expression: P = 0.0009, Granzyme B release: P = 0.0001). Importantly, cytomegalovirus (CMV)-specific responses were not found significantly altered in SLE patients. Furthermore, we demonstrate that EBV-specific CD8+ T cell impairment is a consequence of their Programmed Death 1 (PD-1) receptor up-regulation, as blocking this pathway reverses the dysfunctional phenotype. Finally, prospective monitoring of lupus patients revealed that disease flares precede EBV reactivation. In conclusion, EBV-specific CD8+ T cell responses in SLE patients are functionally impaired, but EBV reactivation appears to be an aggravating consequence rather than a cause of SLE immunopathology. We therefore propose that autoimmune B cell activation during flares drives frequent EBV reactivation, which contributes in a vicious circle to the perpetuation of immune activation in SLE patients

Présence de Cacyreus marshalli Butler dans les départements du Rhône et de la Haute-Loire (Lepidoptera Lycaenidae)

Occurrence of Cacyreus marshalli Butler in Rhône and Haute-Loire districts (France) (Lepidoptera Lycaenidae) Records of Cacyreus marshalli in Rhône and Haute-Loire shows that this species is expanding northward.Les observations de Cacyreus marshalli dans le Rhône et la Haute-Loire montrent que l'expansion de l'espèce vers le nord se poursuit.Girod Christophe, Sauce René. Présence de Cacyreus marshalli Butler dans les départements du Rhône et de la Haute-Loire (Lepidoptera Lycaenidae). In: Bulletin mensuel de la Société linnéenne de Lyon, 71ᵉ année, n°7, septembre 2002. pp. 275-276

Alloreactivity of ex vivo-expanded T cells is correlated with expansion and CD4/CD8 ratio.

International audienceBackground We have demonstrated previously that retroviral-mediated transfer of a suicide gene into bone marrow (BM) donor T cells allows an efficient control of graft-versus-host disease (GvHD) after allogeneic BM transplantation. However, the 12 days of ex vivo culture required for the production of gene-modified cells (GMC), including soluble CD3 monoclonal antibody (MAb)-mediated activation and expansion with interleukin (IL)-2, induced a decrease of GMC alloreactivity and a reversal of their CD4/CD8 ratio. Improving the culture protocol in order to maintain the highest alloreactivity is of critical importance in obtaining an optimal graft-versus-leukemia (GvL) effect. Methods Peripheral blood mononuclear cells were activated with soluble CD3 MAb or CD3 and CD28 MAb co-immobilized on beads and expanded for 12 days in the presence of IL-2, IL-7 or IL-15 before analysis of alloreactivity and phenotype. Results Replacing the CD3 MAb by CD3/CD28 beads led to similar in vitro alloreactivity but improved the expansion and in vivo alloreactivity of GMC. Replacing the IL-2 with IL-7, but not IL-15, or decreasing IL-2 or IL-7 concentrations, improved the in vitro alloreactivity of expanded cells but was associated with lower expansion. Indeed, the alloreactivity of expanded cells was negatively correlated with cell expansion and positively correlated with CD4/CD8 ratio and CD8 expression level. Discussion Quantitative (i.e. low CD4/CD8 ratio) and qualitative (e.g. low CD8 expression) defects may account for the decreased alloreactivity of GMC. Using CD3/CD28 beads and/or IL-7 is more beneficial than CD3 MAb and IL-2 for preventing perturbations of the alloreactivity and phenotype of GMC

Transcriptome of retrovirally transduced CD8+ lymphocytes: influence of cell activation, transgene integration, and selection process.

International audienceA suicide gene introduced by retroviral means can allow in vivo control of alloreactivity mediated by donor gene-modified T cells (GMTC) after allogeneic hematopoietic stem cell transplantation. The present study establishes the transcriptomic profile of GMTC prepared according to the GMTC production process used in our clinical trial (activation/selection methods, CD3/NeoR), which was previously demonstrated to induce phenotypical and functional alterations. This transcriptomic profile was compared with that of GMTC prepared by a novel process (CD3-CD28/DeltaNGFR-MACS) that limits alterations. Using a human pan-genomic microarray and GeneSpring software, we determined the gene expression profiles of CD8+ T cells from four healthy donors before and after the different steps required for gene modification. This analysis revealed that the gene expression pattern of GMTC is affected mainly by the activation step. Specific analysis of GMTC production processes showed that DeltaNGFR-MACS selection combined with CD3-CD28 activation limits the aberrant expression of genes involved in immunological functions and apoptotic pathways. Furthermore, our results indicate a limited risk of oncogenesis associated with retroviral-mediated gene transfer in CD8+ cells, a lower perturbation of the cell cycle regulation pathway after CD3-CD28 activation than after CD3 activation, and no significant involvement of the DeltaNGFR transduction signaling pathway when DeltaNGFR is used for selection. Moreover, genes that might be targeted to limit T cell functional alterations after ex vivo manipulation and culture were identified. These findings should be relevant to further adoptive T cell immunotherapy trials using ex vivo-expanded, gene-modified or unmodified T cells

Early immune response against retrovirally transduced herpes simplex virus thymidine kinase-expressing gene-modified T cells coinfused with a T cell-depleted marrow graft: an altered immune response?

International audienceAdministration of herpes simplex thymidine kinase (HSV-tk)-expressing, gene-modified T cells (GMCs) with T cell-depleted bone marrow transplantation (TCD-BMT) can allow modulation of posttransplantation alloreactivity. Twelve patients received 2 x 10(5) to 2 x 10(6) CD3+ donor GMCs per kilogram with HLA-identical sibling TCD-BMT. Despite extensive T cell depletion of bone marrow, an intensive conditioning regimen, and immunosuppressive graft-versus-host disease (GvHD) prophylaxis, infusion at the time of TCD-BMT of this low number of GMCs sufficed to induce a rapid GMC-specific immune response, as detected by interferon- enzyme- linked immunospot assay in six of eight patients, preferentially targeting HSV-tk. Maximal responses were reached early (median time, 49 [35-68] days post-BMT), with a subsequent rapid and significant decrease in five of six evaluable patients. Immune responses were negatively correlated with the maximal circulating GMC counts. However, such immune response did not result in the elimination of circulating GMCs and was not associated with measurable ex vivo cytotoxic activity against GMCs. Furthermore, alloreactive GMCs still could induce GCV-sensitive GvHD in one patient despite an ongoing immune response. Overall, infusion of HSV-tk-expressing GMCs at the time of BMT results in an early immune response. Such immune response may be altered and may not prevent persistent GCV-sensitive alloreactivity

Multiparameter grouping delineates heterogeneous populations of human IL-17 and/or IL-22 T-cell producers that share antigen specificities with other T-cell subsets

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LOX-1-Expressing Immature Neutrophils Identify Critically-Ill COVID-19 Patients at Risk of Thrombotic Complications

International audienceBackground: Lymphopenia and the neutrophil/lymphocyte ratio may have prognostic value in COVID-19 severity.Objective: We investigated neutrophil subsets and functions in blood and bronchoalveolar lavage (BAL) of COVID-19 patients on the basis of patients’ clinical characteristics.Methods: We used a multiparametric cytometry profiling based to mature and immature neutrophil markers in 146 critical or severe COVID-19 patients.Results: The Discovery study (38 patients, first pandemic wave) showed that 80% of Intensive Care Unit (ICU) patients develop strong myelemia with CD10−CD64+ immature neutrophils (ImNs). Cellular profiling revealed three distinct neutrophil subsets expressing either the lectin‐like oxidized low‐density lipoprotein receptor‐1 (LOX‐1), the interleukin-3 receptor alpha (CD123), or programmed death-ligand 1 (PD-L1) overrepresented in ICU patients compared to non-ICU patients. The proportion of LOX-1- or CD123-expressing ImNs is positively correlated with clinical severity, cytokine storm (IL-1β, IL-6, IL-8, TNFα), acute respiratory distress syndrome (ARDS), and thrombosis. BALs of patients with ARDS were highly enriched in LOX-1-expressing ImN subsets and in antimicrobial neutrophil factors. A validation study (118 patients, second pandemic wave) confirmed and strengthened the association of the proportion of ImN subsets with disease severity, invasive ventilation, and death. Only high proportions of LOX-1-expressing ImNs remained strongly associated with a high risk of severe thrombosis independently of the plasma antimicrobial neutrophil factors, suggesting an independent association of ImN markers with their functions.Conclusion: LOX-1-expressing ImNs may help identifying COVID-19 patients at high risk of severity and thrombosis complications

Influence of Progenitor-Derived Regeneration Markers on Hepatitis C Virus-Related Cirrhosis Outcome (ANRS CO12 CirVir Cohort)

International audienceProgenitor-derived regeneration gives rise to the aberrant expression of biliary markers such as cytokeratin 7 (K7) and epithelial cell adhesion molecule (EpCAM) in hepatocytes. We aimed to describe the expression of these molecules in patients with compensated hepatitis C virus (HCV)-related cirrhosis and to investigate its potential influence on cirrhosis complications. Among patients with Child-Pugh A uncomplicated HCV-related cirrhosis enrolled in the prospective ANRS CO12 CirVir cohort, we selected individuals with a liver biopsy collected within 2 years before inclusion in the study. K7 and EpCAM immunostaining identified intermediate hepatobiliary cells. The influence of biliary marker expres-sion in hepatocytes on decompensation events and the occurrence of hepatocellular carcinoma (HCC) was studied using a multivariate Cox proportional hazards regression model. Among the 337 patients eligible for the study (men, 67%; median age, 52 years), 198 (58.8%) had biopsies with K7-positive hepatocytes including extensive staining in 40 (11.9%) and 203 had EpCAM-positive hepatocytes (60.6%). During follow-up (median, 54.2 months), 47 patients (14%) experienced a decompensation event, and HCC was diagnosed in 37 patients (11%). Extensive K7 staining was independently associated with the occurrence of a decompensation event (hazard ratio [HR], 3.00; 95% confidence interval [CI], 1.30-6.89; P = 0.010). EpCAM expression was independently associated with HCC occurrence (HR, 2.37; 95% CI, 1.07-5.23; P =0.033) along with age and a low prothrombin ratio

Evidence of premature immune aging in patients thymectomized during early childhood.

International audienceWhile the thymus is known to be essential for the initial production of T cells during early life, its contribution to immune development remains a matter of debate. In fact, during cardiac surgery in newborns, the thymus is completely resected to enable better access to the heart to correct congenital heart defects, suggesting that it may be dispensable during childhood and adulthood. Here, we show that young adults thymectomized during early childhood exhibit an altered T cell compartment. Specifically, absolute CD4+ and CD8+ T cell counts were decreased, and these T cell populations showed substantial loss of naive cells and accumulation of oligoclonal memory cells. A subgroup of these young patients (22 years old) exhibited a particularly altered T cell profile that is usually seen in elderly individuals (more than 75 years old). This condition was directly related to CMV infection and the induction of strong CMV-specific T cell responses, which may exhaust the naive T cell pool in the absence of adequate T cell renewal from the thymus. Together, these marked immunological alterations are reminiscent of the immune risk phenotype, which is defined by a cluster of immune markers predictive of increased mortality in the elderly. Overall, our data highlight the importance of the thymus in maintaining the integrity of T cell immunity during adult life