Elevated serum angiotensin converting enzyme correlates with specific HLA-DRB1 alleles and extrapulmonary manifestations in sarcoidosis.

Background: Genetics influence the clinical picture in sarcoidosis, a granulomatous heterogeneous disease often accompanied by elevated serum angiotensin converting enzyme (s-ACE). We aimed to investigate if certain HLA-DRB1 alleles correlate with the levels of s-ACE, known as a marker of the granuloma burden.

Methods: Medical journals of patients with sarcoidosis from a Swedish clinical registry were retrospectively examined to extract the highest recorded s-ACE value and analysed in relation to patient characteristics including phenotype [Löfgren syndrome (LS)/ non-LS], chest X-ray staging according to Scadding, treatment with immunosuppressants, presence of extrapulmonary manifestations (EPM), HLA-DRB1 alleles and prognosis (resolving vs.

Inflammatory plasma protein levels are elevated years before sarcoidosis diagnosis: a nested case-control study in Sweden.

Background: Sarcoidosis is an immune-mediated inflammatory disease whose natural development is not well understood. We aimed to determine if inflammatory plasma protein levels are elevated before sarcoidosis diagnosis compared to controls. Furthermore, we investigated which proteins are increased and how long before diagnosis they are increased.

SARS-CoV-2 infection induces hyaluronan production and hyaluronan levels in COVID-19 patients relate to morbidity and long-term lung impairment: a prospective cohort study.

We previously demonstrated that the lungs of deceased COVID-19 patients were filled with a clear hydrogel consisting of hyaluronan (HA). In this translational study, we investigated the role of HA at all stages of COVID-19 disease to map the consequences of elevated HA on morbidity and identify the mechanism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced HA production. A reduced alveolar surface area was observed in the lungs of deceased COVID-19 patients compared to healthy controls, as visualized by a 3D rendering of lung morphology using light-sheet fluorescence microscopy.

A genetically engineered therapeutic lectin inhibits human influenza A virus infection and sustains robust virus-specific CD8 T cell expansion.

Native banana lectin (BanLec) is antiviral but highly mitogenic, which limits its therapeutic value. In contrast, the genetically engineered H84T BanLec (H84T) is not mitogenic but remains effective against influenza A virus (IAV) infection in mouse models. However, the potency and effect of H84T on human immune cells and IAV-specific immune responses is undetermined.

Innate lymphoid cells are activated in HFRS, and their function can be modulated by hantavirus-induced type I interferons.

Hantaviruses cause the acute zoonotic diseases hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). Infected patients show strong systemic inflammation and immune cell activation. NK cells are highly activated in HFRS, suggesting that also other innate lymphoid cells (ILCs) might be responding to infection.

The immunopathogenesis of sarcoidosis.

Sarcoidosis is a granulomatous multiorgan disease, thought to result from exposure to yet unidentified antigens in genetically susceptible individuals. The exaggerated inflammatory response that leads to granuloma formation is highly complex and involves the innate and adaptive immune system. Consecutive immunological studies using advanced technology have increased our understanding of aberrantly activated immune cells, mediators and pathways that influence the formation, maintenance and resolution of granulomas.

Comparison of SARS-CoV-2 spike-specific IgA and IgG in nasal secretions, saliva and serum.

Introduction: Several novel vaccine platforms aim at mucosal immunity in the respiratory tract to block SARS-CoV-2 transmission. Standardized methods for mucosal sample collection and quantification of mucosal antibodies are therefore urgently needed for harmonized comparisons and interpretations across mucosal vaccine trials and real-world data.

Methods: Using commercial electrochemiluminescence antibody panels, we compared SARS-CoV-2 spike-specific IgA and IgG in paired saliva, nasal secretions, and serum from 1048 healthcare workers with and without prior infection.

Human influenza virus infection elicits distinct patterns of monocyte and dendritic cell mobilization in blood and the nasopharynx.

During respiratory viral infections, the precise roles of monocytes and dendritic cells (DCs) in the nasopharynx in limiting infection and influencing disease severity are incompletely described. We studied circulating and nasopharyngeal monocytes and DCs in healthy controls (HCs) and in patients with mild to moderate infections (primarily influenza A virus [IAV]). As compared to HCs, patients with acute IAV infection displayed reduced DC but increased intermediate monocytes frequencies in blood, and an accumulation of most monocyte and DC subsets in the nasopharynx.

Respiratory and systemic monocytes, dendritic cells, and myeloid-derived suppressor cells in COVID-19: Implications for disease severity.

Since the beginning of the SARS-CoV-2 pandemic in 2020, researchers worldwide have made efforts to understand the mechanisms behind the varying range of COVID-19 disease severity. Since the respiratory tract is the site of infection, and immune cells differ depending on their anatomical location, studying blood is not sufficient to understand the full immunopathogenesis in patients with COVID-19. It is becoming increasingly clear that monocytes, dendritic cells (DCs), and monocytic myeloid-derived suppressor cells (M-MDSCs) are involved in the immunopathology of COVID-19 and may play important roles in determining disease severity.

Impaired oxygen-sensitive regulation of mitochondrial biogenesis within the von Hippel-Lindau syndrome.

Mitochondria are the main consumers of oxygen within the cell. How mitochondria sense oxygen levels remains unknown. Here we show an oxygen-sensitive regulation of TFAM, an activator of mitochondrial transcription and replication, whose alteration is linked to tumours arising in the von Hippel-Lindau syndrome.

Comparison of Lung-Homing Receptor Expression and Activation Profiles on NK Cell and T Cell Subsets in COVID-19 and Influenza.

Respiratory viral infections with SARS-CoV-2 and influenza viruses commonly induce a strong infiltration of immune cells into the human lung, with potential detrimental effects on the integrity of the lung tissue. Despite comprising the largest fractions of circulating lymphocytes in the lung, rather little is known about how peripheral blood natural killer (NK) cell and T cell subsets are equipped for lung-homing in COVID-19 and influenza. Here, we provide a detailed comparative analysis of NK cells and T cells in patients infected with SARS-CoV-2 or influenza virus, focusing on the protein and gene expression of chemokine receptors known to be involved in recruitment to the lung.

Airway antibodies emerge according to COVID-19 severity and wane rapidly but reappear after SARS-CoV-2 vaccination.

Understanding the presence and durability of antibodies against SARS-CoV-2 in the airways is required to provide insights into the ability of individuals to neutralize the virus locally and prevent viral spread. Here, we longitudinally assessed both systemic and airway immune responses upon SARS-CoV-2 infection in a clinically well-characterized cohort of 147 infected individuals representing the full spectrum of COVID-19 severity, from asymptomatic infection to fatal disease. In addition, we evaluated how SARS-CoV-2 vaccination influenced the antibody responses in a subset of these individuals during convalescence as compared with naive individuals.

Correction: Monocyte subset redistribution from blood to kidneys in patients with Puumala virus caused hemorrhagic fever with renal syndrome.

[This corrects the article DOI: 10.1371/journal.ppat.

Pulmonary and blood dendritic cells from sarcoidosis patients more potently induce IFNγ-producing Th1 cells compared with monocytes.

Sarcoidosis is a systemic inflammatory disease mainly affecting the lungs. The hallmark of sarcoidosis are granulomas that are surrounded by activated T cells, likely targeting the disease-inducing antigen. IFNγ-producing Th1 and Th17.