Persistence of circulating CD169+monocytes and HLA-DR downregulation underline the immune response impairment in PASC individuals: the potential contribution of different COVID-19 pandemic waves.

The use of CD169 as a marker of viral infection has been widely discussed in the context of COVID-19, and in particular, its crucial role in the early detection of SARS-CoV-2 infection and its association with the severity and clinical outcome of COVID-19 were demonstrated. COVID-19 patients show relevant systemic alteration and immunological dysfunction that persists in individuals with post-acute sequelae of SARS-CoV-2 infection (PASC). It is critical to implement the characterization of the disease, focusing also on the possible impact of the different COVID-19 waves and the consequent effects found after infection.

The Association of Low CD4 Expression on Monocytes and Low CD8+ T-Cell Count at Hospital Admission Predicts the Need for Mechanical Ventilation in Patients With COVID-19 Pneumonia: A Prospective Monocentric Cohort Study.

Unlabelled: To identify COVID-19-associated immunophenotyping patterns at hospital admission and to determine if some patterns could predict the need for mechanical ventilation (MV).

Design: Prospective observational monocentric cohort study.

Setting: A university-affiliated hospital in Marseille, France.

SARS-CoV-2 spike protein induces a differential monocyte activation that may contribute to age bias in COVID-19 severity.

A strong bias related to age is observed in COVID-19 patients with pediatric subjects developing a milder disease than adults. We hypothesized that a specific SARS-CoV-2 effect conjugated with preexisting differences in the immune systems may explain this. Using flow cytometry, we investigated basal immune differences in a cohort consisting of 16 non-infected young and 16 aged individuals and further leveraged an in vitro whole blood model of SARS-CoV-2 infection so that functional differences could be mined as well.

Small molecules to regulate the GH/IGF1 axis by inhibiting the growth hormone receptor synthesis.

Growth hormone (GH) and insulin-like growth factor-1 (IGF1) play an important role in mammalian development, cell proliferation and lifespan. Especially in cases of tumor growth there is an urgent need to control the GH/IGF1 axis. In this study we screened a 38,480-compound library, and in two consecutive rounds of analogues selection, we identified active lead compounds based on the following criteria: inhibition the GH receptor (GHR) activity and its downstream effectors Jak2 and STAT5, and inhibition of growth of breast and colon cancer cells.

A rapid, easy, and scalable whole blood monocyte CD169 assay for outpatient screening during SARS-CoV-2 outbreak, and potentially other emerging disease outbreaks.

Objective: The COVID-19 corona virus disease outbreak is globally challenging health systems and societies. Its diagnosis relies on molecular methods, with drawbacks revealed by mass screening. Upregulation of neutrophil CD64 or monocyte CD169 has been abundantly reported as markers of bacterial or acute viral infection, respectively.

One-step White Blood Cell Extracellular Staining Method for Flow Cytometry.

Flow cytometry is a powerful analytical technique that is increasingly used in scientific investigations and healthcare; however, it requires time-consuming, multi-step sample procedures, which limits its use to specialized laboratories. In this study, we propose a new universal one-step method in which white blood cell staining and red blood cell lysis are carried out in a single step, using a gentle lysis solution mixed with fluorescent antibody conjugates or probes in a dry or liquid format. The blood sample may be obtained from a routine venipuncture or directly from a fingerprick, allowing for near-patient analysis.

Direct freezing of whole blood enables analysis of leucocyte markers by flow cytometry: a proof-of-concept study.

A new one-step flow cytometry procedure has been recently demonstrated for identifying subjects with infections, but only for fresh whole blood samples. The goal of this study was to assess its applicability on frozen samples, by proposing a new method to perform the sample freezing directly and easily. Fresh blood was tested, then frozen either directly or with dimethylsulfoxide and serum.

Cell Analysis from Dried Blood Spots: New Opportunities in Immunology, Hematology, and Infectious Diseases.

Blood cell analysis is a major pillar of biomedical research and healthcare. These analyses are performed in central laboratories. Rapid shipment from collection site to the central laboratories is currently needed because cells and biomarkers degrade rapidly.

CD169 and CD64 could help differentiate bacterial from CoVID-19 or other viral infections in the Emergency Department.

The identification of a bacterial, viral, or even noninfectious cause is essential in the management of febrile syndrome in the emergency department (ED), especially in epidemic contexts such as flu or CoVID-19. The aim was to assess discriminative performances of two biomarkers, CD64 on neutrophils (nCD64) and CD169 on monocytes (mCD169), using a new flow cytometry procedure, in patients presenting with fever to the ED during epidemics. Eighty five adult patients presenting with potential infection were included during the 2019 flu season in the ED of La Timone Hospital.

Monocyte CD169 Expression as a Biomarker in the Early Diagnosis of Coronavirus Disease 2019.

We assessed the expression of CD169, a type I interferon-inducible receptor, on monocytes (monocyte CD169 [mCD169]) in 53 adult patients admitted to the hospital during the coronavirus disease 2019 (COVID-19) outbreak for a suspicion of severe acute respiratory syndrome coronavirus 2 infection. Monocyte CD169 was strongly overexpressed in 30 of 32 (93.7%) confirmed COVID-19 cases, compared with 3 of 21 (14.

Toward Monocyte HLA-DR Bedside Monitoring: A Proof-of-Concept Study.

Objectives: Decreased expression of human leukocyte antigen-DR on monocytes (mHLA-DR) is recognized as the most appropriate marker for the monitoring of immune alterations in septic patients and critically ill subjects. Its measurement has been established for years by flow cytometry, but remains under-used due to pre-analytical constraints. The objectives of the present work were to develop a rapid and robust one-step protocol.

A Granulocytic Signature Identifies COVID-19 and Its Severity.

Background: An unbiased approach to SARS-CoV-2-induced immune dysregulation has not been undertaken so far. We aimed to identify previously unreported immune markers able to discriminate COVID-19 patients from healthy controls and to predict mild and severe disease.

Methods: An observational, prospective, multicentric study was conducted in patients with confirmed mild/moderate (n = 7) and severe (n = 19) COVID-19.

Flow cytometry evaluation of infection-related biomarkers in febrile subjects in the emergency department.

In an Emergency Department (ED), the etiological identification of infected subjects is essential. 13 infection-related biomarkers were assessed using a new flow cytometry procedure. If subjects presented with febrile symptoms at the ED, 13 biomarkers' levels, including CD64 on neutrophils (nCD64) and CD169 on monocytes (mCD169), were tested and compared with clinical records.

Role of the interferons in CD64 and CD169 expressions in whole blood: Relevance in the balance between viral- or bacterial-oriented immune responses.

Introduction: CD64 expression increases on neutrophils during bacterial infections. Recently an increase in CD169 expression has been discovered on monocytes during viral infections. Generally, interferons α (IFNsα) and IFNsγ are key drivers of the infectious host immune response.

Clinical research assessment by flow cytometry of biomarkers for infectious stratification in an Emergency Department.

Management of patients with infections within the Emergency Department (ED) is challenging for practitioners, as the identification of infectious causes remains difficult with current techniques. A new combination of two biomarkers was tested with a new rapid flow cytometry technique. Subjects from the ED were tested for their CD64 on neutrophils (nCD64) and CD169 on monocytes (mCD169) levels and results were compared to their clinical records.

A Novel Rapid Method of Red Blood Cell and Platelet Permeabilization and Staining for Flow Cytometry Analysis.

Background: Flow cytometry essentially focuses on surface-expressed proteins, with few protocols being devoted to intracellular components. We evaluated a two-step procedure using new formaldehyde-free permeabilization and staining reagents that allow the staining of platelets and red blood cells (RBCs) from whole blood.

Methods: Citrated blood was treated with the new staining protocol (NSP) or control reagent (phosphate-buffered solution bovine serum albumin) and stained with antibodies against surface or intracellular markers.

Sensitive and easy screening for circulating tumor cells by flow cytometry.

Circulating Tumor Cells (CTCs) represent an easy, repeatable and representative access to information regarding solid tumors. However, their detection remains difficult because of their paucity, their short half-life, and the lack of reliable surface biomarkers. Flow cytometry (FC) is a fast, sensitive and affordable technique, ideal for rare cells detection.

A novel one-step extracellular staining for flow cytometry: Proof-of-concept on sepsis-related biomarkers.

Background: Flow cytometry is a powerful analytical technique. However, it requires time-consuming, multi-step sample procedure. A new protocol was developed to perform extracellular staining and red blood cell lysis in one step, using dry antibodies.

Role of platelet α2-adrenoreceptor in biological low response to Clopidogrel for patients with non cardioembolic ischemic stroke or transient ischemic attack.

Background And Purpose: Low biological response to Clopidogrel prescribed after non cardioembolic ischemic stroke or transient ischemic attack (TIA) is a major clinical problem and could explain the recurrence of vascular events. Platelet α2-adrenoreceptors are involved in the high residual platelet reactivity in stable coronary artery disease patients on dual antiplatelet therapy. In the present study we investigated the impact of platelet α2-adrenoreceptors on ADP-induced platelet aggregation and on ADP-induced platelet membrane CD62P (P-selectin) expression, a marker of platelet activation on blood samples from patients hospitalized at the acute phase of a non cardioembolic ischemic stroke or TIA.

Specific Pharmacological Profile of A Adenosine Receptor Predicts Reduced Fractional Flow Reserve in Patients With Suspected Coronary Artery Disease.

Background: The rapid and reliable exclusion of myocardial revascularization is a major unmet clinical need in patients with suspected coronary artery disease (CAD) and non-contributive electrocardiography and troponin. Non-invasive tests have high rates of false positives and negatives, and there is no biomarker to assess myocardial ischemia. The presence of spare adenosine A receptors (AR)-characterized by a high dissociation constant/half maximal effective concentration (K/EC) ratio-expressed on peripheral blood mononuclear cells (PBMC) has been associated with ischemia during exercise stress testing in patients with CAD.

Macrothrombocytopenia and dense granule deficiency associated with FLI1 variants: ultrastructural and pathogenic features.

Congenital macrothrombocytopenia is a family of rare diseases, of which a significant fraction remains to be genetically characterized. To analyze cases of unexplained thrombocytopenia, 27 individuals from a patient cohort of the Bleeding and Thrombosis Exploration Center of the University Hospital of Marseille were recruited for a high-throughput gene sequencing study. This strategy led to the identification of two novel variants (c.