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1.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-314098

ABSTRACT

​​Since its recent zoonotic spill-over severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is constantly adapting to the human host as illustrated by the emergence of variants of concern with increased transmissibility and immune evasion. Prolonged replication in immunosuppressed individuals and evasion from spike-specific antibodies is known to drive intra-host SARS-CoV-2 evolution. Here we show for the first time the major role of CD8 T cells in SARS-CoV-2 evolution. In a patient with chronic, ultimately fatal infection, we observed three spike mutations that prevented neutralisation by convalescent plasma therapy. Moreover, at least four mutations in non-spike proteins emerged that hampered CD8 T-cell recognition of mutant epitopes, two of these occurred before spike mutations. A comparison with worldwide sequencing data showed that several of these T-cell escape mutations had emerged independently as homoplasies in multiple circulating lineages. We propose that human leukocyte antigen class I contributes to shaping the evolutionary landscape of SARS-CoV-2.

2.
Dtsch Med Wochenschr ; 146(13-14): 899-903, 2021 Jul.
Article in German | MEDLINE | ID: covidwho-1493267

ABSTRACT

Infection with SARS-CoV-2 has a profound influence on the hematopoetic system that mediates clinical symptoms and mortality. Several studies have shown that treatment of the cytokine storm (CRS) with anti-inflammatory drugs like dexamethasone and tocilizumab can significantly improve survival. Systematic reviews confirm the safety of convalescent plasma administration and offer initial indications of its effectiveness in certain groups. COVID-associated coagulopathy (CAC) and vaccine-induced immune thrombotic thrombocytopenia (VITT) represent severe infection- or vaccination associated complications that require a specific diagnostic and therapeutic workup.


Subject(s)
COVID-19/blood , COVID-19/complications , Hematology , Hematopoiesis , Hemostasis , SARS-CoV-2/physiology , Blood Coagulation Disorders/etiology , Blood Coagulation Disorders/prevention & control , Blood Coagulation Disorders/therapy , COVID-19/mortality , COVID-19/therapy , Humans , Immunization, Passive
3.
PLoS Pathog ; 17(10): e1009742, 2021 10.
Article in English | MEDLINE | ID: covidwho-1456098

ABSTRACT

Disease manifestations in COVID-19 range from mild to severe illness associated with a dysregulated innate immune response. Alterations in function and regeneration of dendritic cells (DCs) and monocytes may contribute to immunopathology and influence adaptive immune responses in COVID-19 patients. We analyzed circulating DC and monocyte subsets in 65 hospitalized COVID-19 patients with mild/moderate or severe disease from acute illness to recovery and in healthy controls. Persisting reduction of all DC subpopulations was accompanied by an expansion of proliferating Lineage-HLADR+ cells lacking DC markers. Increased frequency of CD163+ CD14+ cells within the recently discovered DC3 subpopulation in patients with more severe disease was associated with systemic inflammation, activated T follicular helper cells, and antibody-secreting cells. Persistent downregulation of CD86 and upregulation of programmed death-ligand 1 (PD-L1) in conventional DCs (cDC2 and DC3) and classical monocytes associated with a reduced capacity to stimulate naïve CD4+ T cells correlated with disease severity. Long-lasting depletion and functional impairment of DCs and monocytes may have consequences for susceptibility to secondary infections and therapy of COVID-19 patients.


Subject(s)
COVID-19/immunology , Dendritic Cells/immunology , Regeneration/immunology , SARS-CoV-2/immunology , Adult , Antigens, CD/immunology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/pathology , COVID-19/pathology , Dendritic Cells/pathology , Female , Humans , Male , Middle Aged , Monocytes/immunology , Monocytes/pathology , Programmed Cell Death 1 Receptor/immunology
4.
Hemasphere ; 5(7): e603, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1301392

ABSTRACT

The clinical and immunological impact of B-cell depletion in the context of coronavirus disease 2019 (COVID-19) is unclear. We conducted a prospectively planned analysis of COVID-19 in patients who received B-cell depleting anti-CD20 antibodies and chemotherapy for B-cell lymphomas. The control cohort consisted of age- and sex-matched patients without lymphoma who were hospitalized because of COVID-19. We performed detailed clinical analyses, in-depth cellular and molecular immune profiling, and comprehensive virological studies in 12 patients with available biospecimens. B-cell depleted lymphoma patients had more severe and protracted clinical course (median hospitalization 88 versus 17 d). All patients actively receiving immunochemotherapy (n = 5) required ICU support including long-term mechanical ventilation. Neutrophil recovery following granulocyte colony stimulating factor stimulation coincided with hyperinflammation and clinical deterioration in 4 of the 5 patients. Immune cell profiling and gene expression analysis of peripheral blood mononuclear cells revealed early activation of monocytes/macrophages, neutrophils, and the complement system in B-cell depleted lymphoma patients, with subsequent exacerbation of the inflammatory response and dysfunctional interferon signaling at the time of clinical deterioration of COVID-19. Longitudinal immune cell profiling and functional in vitro assays showed SARS-CoV-2-specific CD8+ and CD4+ T-effector cell responses. Finally, we observed long-term detection of SARS-CoV-2 in respiratory specimens (median 84 versus 12 d) and an inability to mount lasting SARS-CoV-2 antibody responses in B-cell depleted lymphoma patients. In summary, we identified clinically relevant particularities of COVID-19 in lymphoma patients receiving B-cell depleting immunochemotherapies.

5.
Dtsch Med Wochenschr ; 145(15): 1044-1050, 2020 Jul.
Article in German | MEDLINE | ID: covidwho-691147

ABSTRACT

Infection with SARS-COV-2 leads to a number of pathologies in the hematopoetic system that have significant impact on clinical symptoms and mortality. There are 3 stages of infection: (1) early upper respiratory tract infection with fever and lymphopenia (2) pulmonary phase and (3) hyperinflammatory phase with the clinical signs of organ failure such as ARDS/shock. Hyperinflammation, which is triggered by activation of T cells and monocytes/macrophages, is essential for organ pathologies. Interferon IFN-É£, tumor necrosis factor (TNF)-α, IL-10 and interleukin-6 (IL-6) play important roles as mediators of inflammation. In analogy to the cytokine release syndrome (CRS) after CAR-T cell therapy, the therapeutic activity of the IL-6 receptor antibody tocilizumab is investigated in clinical studies.The coagulation system is activated during the inflammatory phase of COVID infection, most likely on the pathophysiological basis of immune thrombosis. Clinically, there is a significantly increased incidence of venous (especially pulmonary artery embolism), but also arterial thromboembolism (TE). In laboratory chemistry, the D-dimer, fibrinogen but also vWF and FVIII are significantly increased. Guidelines for the prophylaxis and therapy of COVID-associated coagulopathy have been developed. Analogous to other viral infections, there are approaches to passive immunization using convalescent plasma. Its administration has shown promising activity in first uncontrolled case series and is currently being examined in clinical studies worldwide for its therapeutic activity.


Subject(s)
Coronavirus Infections , Hematologic Diseases , Pandemics , Pneumonia, Viral , Betacoronavirus , COVID-19 , Coronavirus Infections/complications , Coronavirus Infections/therapy , Embolism/prevention & control , Embolism/therapy , Embolism/virology , Hematologic Diseases/prevention & control , Hematologic Diseases/therapy , Hematologic Diseases/virology , Humans , Inflammation/prevention & control , Inflammation/therapy , Inflammation/virology , Pneumonia, Viral/complications , Pneumonia, Viral/therapy , SARS-CoV-2
6.
JMIR Public Health Surveill ; 6(2): e19033, 2020 06 01.
Article in English | MEDLINE | ID: covidwho-456495

ABSTRACT

BACKGROUND: From the perspective of health care professionals, coronavirus disease (COVID-19) brings many challenges as well as opportunities for digital health care. One challenge is that health care professionals are at high risk of infection themselves. Therefore, in-person visits need to be reduced to an absolute minimum. Connected care solutions, including telehealth, remote patient monitoring, and secure communications between clinicians and their patients, may rapidly become the first choice in such public health emergencies. OBJECTIVE: The aim of the COVID-19 Caregiver Cockpit (C19CC) was to implement a free-of-charge, web- and app-based tool for patient assessment to assist health care professionals working in the COVID-19 environment. METHODS: Physicians in Argentina, Germany, Iran, Italy, Portugal, Switzerland, and the United States explained their challenges with COVID-19 patient care through unstructured interviews. Based on the collected feedback, the first version of the C19CC was built. In the second round of interviews, the application was presented to physicians, and more feedback was obtained. RESULTS: Physicians identified a number of different scenarios where telemedicine or connected care solutions could rapidly improve patient care. These scenarios included outpatient care, discharge management, remote tracking of patients with chronic diseases, as well as incorporating infected physicians under quarantine into telehealth services. CONCLUSIONS: The C19CC is the result of an agile and iterative development process that complements the work of physicians. It aims to improve the care and safety of people who are infected by COVID-19.


Subject(s)
Coronavirus Infections/therapy , Internet , Mobile Applications , Pneumonia, Viral/therapy , Telemedicine/methods , Ambulatory Care/methods , Attitude of Health Personnel , COVID-19 , Coronavirus Infections/epidemiology , Hospitalization , Humans , Pandemics , Physicians/psychology , Pneumonia, Viral/epidemiology , Qualitative Research , Telemedicine/organization & administration
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