scholarly journals A case report describing the immune response of an infant with congenital heart disease and severe COVID-19

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Danielle Wurzel ◽  
Melanie R. Neeland ◽  
Jeremy Anderson ◽  
Yara-Natalie Abo ◽  
Lien Anh Ha Do ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Acute Infection ◽  
Young Infant ◽  
Immune Memory ◽  
Future Research ◽  
Cell Populations ◽  
Initial Increase ◽  
Immune Correlates ◽  
Cytokine Analysis

Abstract Background Children with SARS-CoV-2 infection generally present with milder symptoms or are asymptomatic in comparison with adults, however severe disease occurs in a subset of children. To date, the immune correlates of severe COVID-19 in young children have been poorly characterised. Methods We report the kinetics of immune responses in relation to clinical and virological features in an infant with acute severe COVID-19 using high-dimensional flow cytometry and multiplex cytokine analysis. Results Systemic cellular and cytokine profiling show an initial increase in neutrophils and monocytes with depletion of lymphoid cell populations (particularly CD8 + T and NK cells) and elevated inflammatory cytokines. Expansion of memory CD4 + T (but not CD8 + T) cells occurred over time, with a predominant Th2 bias. Marked activation of T cell populations observed during the acute infection gradually resolved as the child recovered. Substantial in vitro activation of T-cell populations and robust cytokine production, in response to inactivated SARS-CoV-2 stimulation, was observed 3 months after infection indicating durable, long-lived cellular immune memory. Conclusions These findings provide important insights into the immune response of a young infant with severe COVID-19 and will help to inform future research into therapeutic targets for high-risk groups.

scholarly journals Immune Responses in an Infant with Congenital Heart Disease and Severe COVID-19 

2021 ◽  
Author(s):  
Paul Licciardi ◽  
Danielle Wurzel ◽  
Melanie Neeland ◽  
Jeremy Anderson ◽  
Yara-Natalie Abo ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Severe Disease ◽  
Acute Infection ◽  
Immune Memory ◽  
Cell Populations ◽  
Initial Increase ◽  
Older Children ◽  
Immune Correlates

Abstract Children have lower hospitalisation and mortality rates for coronavirus disease-2019 (COVID-19) than adults; however, younger children (<4 years of age)1 may develop more severe disease than older children. To date, the immune correlates of severe COVID-19 in young children have been poorly characterized. We report the kinetics of immune responses in relation to clinical and virological features in an infant with acute severe COVID-19. Systemic cellular and cytokine profiling showed initial increase in neutrophils and monocytes with depletion of lymphoid cell populations (particularly CD8+ T and NK cells) and elevated inflammatory cytokines. Expansion of memory CD4+T (but not CD8+T) cells occurred over time, with predominant Th2 bias. Marked activation of T cell populations observed during the acute infection gradually resolved as the child recovered. Significant in vitro activation of T-cell populations and robust cytokine production, in response to inactivated SARS-CoV-2 stimulation, was observed 3 months after infection indicating durable, long-lived cellular immune memory.

scholarly journals OP0083 INFECTIOUS AND AUTOINFLAMMATORY MODIC TYPE 1 CHANGES HAVE DIFFERENT PATHOMECHANISMS

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 45.2-45
Author(s):  
I. Heggli ◽  
R. Schüpbach ◽  
N. Herger ◽  
T. A. Schweizer ◽  
A. Juengel ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Immune Response ◽  
T Cell ◽  
Cell Populations ◽  
Gene Set ◽  
Go Enrichment ◽  
Modic Type ◽  
And Control ◽  
Infectious Etiology

Background:Modic type 1 changes (MC1) are vertebral bone marrow (BM) edema that associate with non-specific low back pain (LBP). Two etiologies have been described. In the infectious etiology the anaerobic aerotolerant Cutibacterium acnes (C. acnes) invades damaged intervertebral discs (IVDs) resulting in disc infection and endplate damage, which leads to the evocation of an immune response. In the autoinflammatory etiology disc and endplate damage lead to the exposure of immune privileged disc cells and matrix to leukocytes, thereby evoking an immune response in the BM. Different etiologies require different treatment strategies. However, it is unknown if etiology-specific pathological mechanisms exist.Objectives:The aim of this study was to identify etiology-specific dysregulated pathways of MC1 and to perform in-depth analysis of immune cell populations of the autoinflammatory etiology.Methods:BM aspirates and biopsies were obtained from LBP patients with MC1 undergoing spinal fusion. Aspirates/biopsies were taken prior screw insertion through the pedicle screw trajectory. From each patient, a MC1 and an intra-patient control aspiration/biopsy from the adjacent vertebral level was taken. If C. acnes in IVDs adjacent to MC1 were detected by anaerobic bacterial culture, patients were assigned to the infectious, otherwise to the autoinflammatory etiology.Total RNA was isolated from aspirates and sequenced (Novaseq) (infectious n=3 + 3, autoinflammatory n=5 + 5). Genes were considered as differentially expressed (DEG) if p-value < 0.01 and log2fc > ± 0.5. Gene ontology (GO) enrichment was performed in R (GOseq), gene set enrichment analysis (GSEA) with GSEA software.Changes in cell populations of the autoinflammatory etiology were analyzed with single cell RNA sequencing (scRNAseq): Control and MC1 biopsies (n=1 + 1) were digested, CD45+CD66b- mononuclear cells isolated with fluorescence activated cell sorting (FACS), and 10000 cells were sequenced (10x Genomics). Seurat R toolkit was used for quality-control, clustering, and differential expression analysis.Transcriptomic changes (n=5 + 5) of CD45+CD66b+ neutrophils isolated with flow cytometry from aspirates were analyzed as for total bulk RNAseq. Neutrophil activation (n=3 + 3) was measured as CD66b+ expression with flow cytometry. CD66bhigh and CD66blow fractions in MC1 and control neutrophils were compared with paired t-test.Results:Comparing MC1 to control in total bulk RNAseq, 204 DEG in the autoinflammatory and 444 DEG in the infectious etiology were identified with only 67 shared genes (Fig. 1a). GO enrichment revealed “T-cell activation” (p = 2.50E-03) in the autoinflammatory and “complement activation, classical pathway” (p=1.1E-25) in the infectious etiology as top enriched upregulated biological processes (BP) (Fig 1b). ScRNAseq of autoinflammatory MC1 showed an overrepresentation of T-cells (p= 1.00E-34, OR=1.54) and myelocytes (neutrophil progenitor cells) (p=4.00E-05, OR=2.27) indicating an increased demand of these cells (Fig. 1c). Bulk RNAseq analysis of neutrophils from the autoinflammatory etiology revealed an activated, pro-inflammatory phenotype (Fig 1d), which was confirmed with more CD66bhigh neutrophils in MC1 (+11.13 ± 2.71%, p=0.02) (Fig. 1e).Figure 1.(a) Venn diagram of DEG from total bulk RNAseq (b) Top enriched upregulated BP of autoinflammatory (left) and infectious (right) etiology (c) Cell clustering of autoinflammatory MC1 BM (d) Enrichment of “inflammatory response” gene set in autoinflammatory MC1 neutrophils (e) Representative histogram of CD66b+ expression in MC1 and control neutrophils.Conclusion:Autoinflammatory and infectious etiologies of MC1 have different pathological mechanisms. T-cell and neutrophil activation seem to be important in the autoinflammatory etiology. This has clinical implication as it could be explored for diagnostic approaches to distinguish the two MC1 etiologies and supports developing targeted treatments for both etiologies.Disclosure of Interests:None declared

Introduction to Clinical Immunology: Overview of the Immune Response, Autoimmune Conditions, and Immunosuppressive Therapeutics for Rheumatic Diseases

2016 ◽  
Author(s):  
Steven K. Lundy ◽  
Alison Gizinski ◽  
David A. Fox
Keyword(s):  
Immune Response ◽  
Immune System ◽  
T Cell ◽  
Immune Responses ◽  
Autoimmune Diseases ◽  
Adaptive Immunity ◽  
Cell Populations ◽  
Hematopoietic Stem ◽  
Innate And Adaptive Immunity ◽  
Adaptive Immune

The immune system is a complex network of cells and mediators that must balance the task of protecting the host from invasive threats. From a clinical perspective, many diseases and conditions have an obvious link to improper functioning of the immune system, and insufficient immune responses can lead to uncontrolled acute and chronic infections. The immune system may also be important in tumor surveillance and control, cardiovascular disease, health complications related to obesity, neuromuscular diseases, depression, and dementia. Thus, a working knowledge of the role of immunity in disease processes is becoming increasingly important in almost all aspects of clinical practice. This review provides an overview of the immune response and discusses immune cell populations and major branches of immunity, compartmentalization and specialized immune niches, antigen recognition in innate and adaptive immunity, immune tolerance toward self antigens, inflammation and innate immune responses, adaptive immune responses and helper T (Th) cell subsets, components of the immune response that are important targets of treatment in autoimmune diseases, mechanisms of action of biologics used to treat autoimmune diseases and their approved uses, and mechanisms of other drugs commonly used in the treatment of autoimmune diseases. Figures show the development of erythrocytes, platelets, lymphocytes, and other immune system cells originating from hematopoietic stem cells that first reside in the fetal liver and later migrate to the bone marrow, antigen–major histocompatibility complex recognition by T cell receptor control of T cell survival and activation, and Th cells as central determinants of the adaptive immune response toward different stimuli. Tables list cell populations involved in innate and adaptive immunity, pattern recognition receptors with known ligands, autoantibody-mediated human diseases: examples of pathogenic mechanisms, selected Food and Drug Administration–approved autoimmune disease indications for biologics, and mechanism of action of biologics used to treat autoimmune diseases.   This review contains 3 highly rendered figures, 5 tables, and 64 references.

scholarly journals Race between Retroviral Spread and CD4+ T-Cell Response Determines the Outcome of Acute Friend Virus Infection

2009 ◽  
Vol 83 (21) ◽  
pp. 11211-11222 ◽  
Author(s):  
Rebecca Pike ◽  
Andrew Filby ◽  
Mickaël J.-Y. Ploquin ◽  
Urszula Eksmond ◽  
Rute Marques ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Cell Response ◽  
Acute Infection ◽  
T Cell Response ◽  
Friend Virus ◽  
Antiviral Immune Response ◽  
Ultimate Failure ◽  
Necessary And Sufficient

ABSTRACT Retroviruses can establish persistent infection despite induction of a multipartite antiviral immune response. Whether collective failure of all parts of the immune response or selective deficiency in one crucial part underlies the inability of the host to clear retroviral infections is currently uncertain. We examine here the contribution of virus-specific CD4+ T cells in resistance against Friend virus (FV) infection in the murine host. We show that the magnitude and duration of the FV-specific CD4+ T-cell response is directly proportional to resistance against acute FV infection and subsequent disease. Notably, significant protection against FV-induced disease is afforded by FV-specific CD4+ T cells in the absence of a virus-specific CD8+ T-cell or B-cell response. Enhanced spread of FV infection in hosts with increased genetic susceptibility or coinfection with Lactate dehydrogenase-elevating virus (LDV) causes a proportional increase in the number of FV-specific CD4+ T cells required to control FV-induced disease. Furthermore, ultimate failure of FV/LDV coinfected hosts to control FV-induced disease is accompanied by accelerated contraction of the FV-specific CD4+ T-cell response. Conversely, an increased frequency or continuous supply of FV-specific CD4+ T cells is both necessary and sufficient to effectively contain acute infection and prevent disease, even in the presence of coinfection. Thus, these results suggest that FV-specific CD4+ T cells provide significant direct protection against acute FV infection, the extent of which critically depends on the ratio of FV-infected cells to FV-specific CD4+ T cells.

scholarly journals Impact of Low-Dose Occupational Exposure to Ionizing Radiation on T-Cell Populations and Subpopulations and Humoral Factors Included in the Immune Response

Dose-Response ◽  
2018 ◽  
Vol 16 (3) ◽  
pp. 155932581878556 ◽  
Author(s):  
Ilona Gyuleva ◽  
Jana Djounova ◽  
Ivanka Rupova
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Occupational Exposure ◽  
Low Dose ◽  
Dose Range ◽  
Interleukin 2 ◽  
Cell Populations ◽  
Control Group ◽  
T Helper ◽  
Humoral Factors

The aim of the present study is to assess the effects of low-dose occupational exposure on T helper response. One Hundred five employees working in Nuclear Power Plant, Kozloduy, Bulgaria and control group of 32 persons are included in this investigation. Flow cytometry measurements of T-cell populations and subpopulations and natural killer T cells are performed and levels of G, A, and M immunoglobulins and interleukin 2 (IL-2), IL-4, and interferon γ were determined. The data interpreted with regard to cumulative doses, length of service, and age. The results of the present study are not enough to outline a clear impact of occupational radiation exposure on T helper populations. Nevertheless, the observed even slight trends in some lymphocyte’s populations and in cytokines profile give us the reason to assume a possibility of a gradual polarization of T helper 1 to T helper 2 immune response at dose range 100 to 200 mSv. The results of the present study indicate the need to perform a more detailed epidemiological survey including potential confounding and misclassifying factors and possible selection bias that could influence the results.

scholarly journals CD8+ T Cells Participate in the Memory Immune Response to Mycobacterium tuberculosis

2001 ◽  
Vol 69 (7) ◽  
pp. 4320-4328 ◽  
Author(s):  
Natalya V. Serbina ◽  
JoAnne L. Flynn
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Mycobacterium Tuberculosis ◽  
T Cell ◽  
Acute Infection ◽  
Cell Subset ◽  
Ifn Γ ◽  
Memory And Recall ◽  
Memory Immune Response ◽  
Activation Marker Cd69

ABSTRACT The contribution of CD8+ T cells to the control of tuberculosis has been studied primarily during acute infection in mouse models. Memory or recall responses in tuberculosis are less well characterized, particularly with respect to the CD8 T-cell subset. In fact, there are published reports that CD8+ T cells do not participate in the memory immune response to Mycobacterium tuberculosis. We examined the CD8+ T-cell memory and local recall response to M. tuberculosis. To establish a memory immunity model, C57BL/6 mice were infected with M. tuberculosis, followed by treatment with anti-mycobacterial drugs and prolonged rest. The lungs of memory immune mice contained CD4+ and CD8+ T cells with the cell surface phenotype characteristic of memory cells (CD69lowCD25low CD44high). At 1 week postchallenge withM. tuberculosis via aerosol, ≥30% of both CD4+ and CD8+ T cells in the lungs of immune mice expressed the activation marker CD69 and could be restimulated to produce gamma interferon (IFN-γ). In contrast, <6% of T cells in the lungs of naive challenged mice were CD69+ at 1 week postchallenge, and IFN-γ production was not observed at this time point. CD8+ T cells from the lungs of both naive and memory mice after challenge were cytotoxic toward M. tuberculosis-infected macrophages. Our data indicate that memory and recall immunity to M. tuberculosis is comprised of both CD4+ and CD8+ T lymphocytes and that there is a rapid response of both subsets in the lungs following challenge.

scholarly journals Flagellin-Independent Regulation of Chemokine Host Defense in Campylobacter jejuni-Infected Intestinal Epithelium

2006 ◽  
Vol 74 (6) ◽  
pp. 3437-3447 ◽  
Author(s):  
Priscilla A. Johanesen ◽  
Michael B. Dwinell
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Campylobacter Jejuni ◽  
Host Defense ◽  
Intestinal Epithelium ◽  
Diarrheal Disease ◽  
Adaptive Immune Response ◽  
Immune Memory ◽  
Adaptive Immune ◽  
Autoimmune Neuropathy

ABSTRACT Campylobacter jejuni is a leading cause of bacterial food-borne diarrheal disease throughout the world and the most frequent antecedent of autoimmune neuropathy Guillain-Barré syndrome. While infection is associated with immune memory, little is known regarding the role of the epithelium in targeting dendritic cells (DC) for initiating the appropriate adaptive immune response to C. jejuni. The objective of this study was to define the role for the intestinal epithelium in the induction of the adaptive immune response in C. jejuni infection by assessing the production of DC and T-cell chemoattractants. Human T84 epithelial cells were used as model intestinal epithelia. Infection of T84 cells with C. jejuni dose- and time-dependently up-regulated DC and T-cell chemokine gene transcription and secretion. Induction required live bacteria and was in the physiologically relevant direction for attraction of mucosal immunocytes. C. jejuni-activated NF-κB signaling was shown to be essential for proinflammatory chemokine secretion. Notably, C. jejuni secretion occurred independently of flagellin identification by Toll-like receptor 5. Secretion of a DC chemoattractant by differing clinical C. jejuni isolates suggested adherence/invasion were key virulence determinants of epithelial chemokine secretion. The regulated epithelial expression of DC and T-cell chemoattractants suggests a mechanism for the directed trafficking of immune cells required for the initiation of adaptive immunity in campylobacteriosis. Chemokine secretion occurs despite Campylobacter evasion of the flagellin pattern recognition receptor, suggesting that alternate host defense strategies limit disease pathogenesis.

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