Neutrophil phenotype, effector functions and microbicidal activity in SARS-CoV-2-associated ARDS patients.

Critically ill patients admitted to the intensive care unit (ICU) for SARS-CoV-2-induced acute respiratory distress syndrome (ARDS) are at increased risk of bacterial and fungal secondary pulmonary infections due to acquired immune dysfunction. Given that the activity of neutrophils has not been described in these patients, we aimed to investigate the function of neutrophils at ICU admission and on Day 7 (D7) post admission. Neutrophil maturation and several functional indicators were investigated. We detected a significant decrease in reactive oxygen species production at D7, but we did not observe any other significant alterations in neutrophil function. Furthermore, bronchoalveolar lavage obtained from patients displayed no inhibitory effect on the function of neutrophils from healthy donors. These findings indicate that patients admitted to the ICU for SARS-CoV-2-induced ARDS do not acquire neutrophil dysfunction within the first week of their stay, which suggests that nosocomial infections among these patients are not due to acquired neutrophil dysfunctions.

Brexucabtagene autoleucel in relapsed or refractory mantle cell lymphoma, intention-to-treat use in the DESCAR-T registry.

Not available.

Enteral citrulline supplementation versus placebo on SOFA score on day 7 in mechanically ventilated critically ill patients: the IMMUNOCITRE randomized clinical trial.

BACKGROUND: Restoring plasma arginine levels through enteral administration of L-citrulline in critically ill patients may improve outcomes. We aimed to evaluate whether enteral L-citrulline administration reduced organ dysfunction based on the Sequential Organ Failure Assessment (SOFA) score and affected selected immune parameters in mechanically ventilated medical intensive care unit (ICU) patients. METHODS: A randomized, double-blind, multicenter clinical trial of enteral administration of L-citrulline versus placebo for critically ill adult patients under invasive mechanical ventilation without sepsis or septic shock was conducted in four ICUs in France between September 2016 and February 2019. Patients were randomly assigned to receive enteral L-citrulline (5 g) every 12 h for 5 days or isonitrogenous, isocaloric placebo. The primary outcome was the SOFA score on day 7. Secondary outcomes included SOFA score improvement (defined as a decrease in total SOFA score by 2 points or more between day 1 and day 7), secondary infection acquisition, ICU length of stay, plasma amino acid levels, and immune biomarkers on day 3 and day 7 (HLA-DR expression on monocytes and interleukin-6). RESULTS: Of 120 randomized patients (mean age, 60 ± 17 years; 44 [36.7%] women; ICU stay 10 days [IQR, 7-16]; incidence of secondary infections 25 patients (20.8%)), 60 were allocated to L-citrulline and 60 were allocated to placebo. Overall, there was no significant difference in organ dysfunction as assessed by the SOFA score on day 7 after enrollment (4 [IQR, 2-6] in the L-citrulline group vs. 4 [IQR, 2-7] in the placebo group; Mann‒Whitney U test, p = 0.9). Plasma arginine was significantly increased on day 3 in the treatment group, while immune parameters remained unaffected. CONCLUSION: Among mechanically ventilated ICU patients without sepsis or septic shock, enteral L-citrulline administration did not result in a significant difference in SOFA score on day 7 compared to placebo. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT02864017 (date of registration: 11 August 2016).

The Negative Influence of Baseline Cell-free DNA on Long-term Survival in DLBCL Depends on Frontline Treatment Intensity.

PURPOSE: This study aims to investigate the relationship between the intensity of the initial treatment given to patients with de novo diffuse large B-cell lymphoma (DLBCL) and the impact of their baseline cell-free DNA (cfDNA) levels on their long-term survival. EXPERIMENTAL DESIGN: The GOELAMS 075 randomized clinical trial compared rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) with high-dose R-chemotherapy plus autologous stem cell transplantation (R-HDT) for patients aged ≤60. An interim PET assessment was used to refer patients for salvage therapy. With a median follow-up of more than 5.8 years, we analyzed the effects of the treatment arm, salvage therapy, and cfDNA level at diagnosis on overall survival (OS). RESULTS: In a representative group of 123 patients, a high cfDNA concentration (>55 ng/mL) at diagnosis was associated with poor clinical prognostic factors and constituted a prognostic marker, independently of the age-adjusted International Prognostic Index. A cfDNA level above a threshold value of 55 ng/mL at diagnosis was associated with significantly worse OS. In an intention-to-treat analysis, high-cfDNA R-CHOP patients (but not high-cfDNA R-HDT patients) had worse OS [HR (95% confidence interval), 3.99 (1.98-10.74); P = 0.006]. In patients with high cfDNA levels, salvage therapy and transplantation were associated with a significantly higher OS rate. Among 50 patients with complete response 6 months after the end of treatment, for 11 of 24 R-CHOP patients, the cfDNA did not fall back to normal values. CONCLUSIONS: In this randomized clinical trial, intensive regimens mitigated the negative influence of high cfDNA levels in de novo DLBCL, relative to R-CHOP.

Functional specialization of short-lived and long-lived macrophage subsets in human tonsils.

Macrophages play a central role in tissue homeostasis and host defense. However, the properties of human macrophages in non-diseased tissues remain poorly understood. Here, we characterized human tonsil macrophages and identified three subsets with distinct phenotype, transcriptome, life cycle, and function. CD36hi macrophages were related to monocytes, while CD36lo macrophages showed features of embryonic origin and CD36int macrophages had a mixed profile. scRNA-seq on non-human primate tonsils showed that monocyte recruitment did not pre-exist an immune challenge. Functionally, CD36hi macrophages were specialized for stimulating T follicular helper cells, by producing Activin A. Combining reconstruction of ligand-receptor interactions and functional assays, we identified stromal cell-derived TNF-α as an inducer of Activin A secretion. However, only CD36hi macrophages were primed for Activin A expression, via the activity of IRF1. Our results provide insight into the heterogeneity of human lymphoid organ macrophages and show that tonsil CD36hi macrophage specialization is the result of both intrinsic features and interaction with stromal cells.

Demultiplexing Ig repertoires by parallel mRNA/DNA sequencing shows major differential alterations in severe COVID-19.

To understand the fine differential elements that can lead to or prevent acute respiratory distress syndrome (ARDS) in COVID-19 patients, it is crucial to investigate the immune response architecture. We herein dissected the multiple layers of B cell responses by flow cytometry and Ig repertoire analysis from acute phase to recovery. Flow cytometry with FlowSOM analysis showed major changes associated with COVID-19 inflammation such as an increase of double-negative B-cells and ongoing plasma cell differentiation. This paralleled COVID-19-driven expansion of two disconnected B-cell repertoires. Demultiplexing successive DNA and RNA Ig repertoire patterns characterized an early expansion of IgG1 clonotypes with atypically long and uncharged CDR3, the abundance of this inflammatory repertoire being correlated with ARDS and likely pejorative. A superimposed convergent response included convergent anti-SARS-CoV-2 clonotypes. It featured progressively increasing somatic hypermutation together with normal-length or short CDR3 and it persisted until a quiescent memory B-cell stage after recovery.

Blood, Cellular, and Tissular Calcineurin Inhibitors Pharmacokinetic-Pharmacodynamic Relationship in Heart Transplant Recipients: The INTRACAR Study.

BACKGROUND: After heart transplantation, calcineurin inhibitors (CNI) (cyclosporin A and tacrolimus) are key immunosuppressive drugs to prevent graft rejection. Whole-blood concentration (C blood )-guided therapeutic drug monitoring (TDM) is systematically performed to improve graft outcomes. However, some patients will still experience graft rejection and/or adverse events despite CNI C blood within the therapeutic range. Other pharmacokinetic parameters, such as the intragraft, or intracellular concentration at the CNI site of action could refine their TDM. Nonetheless, these remain to be explored. The objective of the INTRACAR study was to describe the relationship between whole blood, intragraft, and intracellular CNI concentrations as well as their efficacy in heart transplant recipients (HTR). METHODS: In a cohort of HTR, protocol endomyocardial biopsies (EMB) were collected to assess rejection by anatomopathological analysis. Part of the EMB was used to measure the intragraft concentrations of CNI (C EMB ). C blood and the concentration inside peripheral blood mononuclear cells, (C PBMC ), a cellular fraction enriched with lymphocytes, were also monitored. Concentrations in the 3 matrices were compared between patients with and without biopsy-proven acute rejection (BPAR). RESULTS: Thirty-four HTR were included, representing nearly 100 pharmacokinetic (PK) samples for each CNI. C blood , C EMB , and C PBMC correlated for both CNI. BPAR was observed in 74 biopsies (39.6%) from 26 patients (76.5%), all except one was of low grade. None of the PK parameters (C blood , C EMB , C PBMC , C EMB/blood , and C PBMC/blood ) was associated with BPAR. CONCLUSIONS: In this cohort of well-immunosuppressed patients, no association was observed for any of the PK parameters, including C blood , with the occurrence of BPAR. However, a trend was noticed for the C EMB and C EMB/blood of cyclosporin A. Further studies in higher-risk patients may help optimize the use of C EMB and C PBMC for CNI TDM in HTR.