Claudia Giesecke

Claudia Giesecke
Max Planck Institute for Molecular Genetics | MOLGEN · Flow Cytometry

Dr. rer. nat.

About

38
Publications
15,677
Reads
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2,481
Citations
Additional affiliations
June 2018 - present
Max Planck Institute for Molecular Genetics
Position
  • Head of Department
May 2016 - May 2018
German Rheumatism Research Centre
Position
  • PostDoc Position
January 2010 - December 2015
Charité Universitätsmedizin Berlin
Position
  • PhD Student

Publications

Publications (38)
Preprint
SARS-CoV-2 mRNA vaccination of healthy individuals is highly immunogenic and protective against severe COVID-19. However, there are limited data on how disease-modifying therapies (DMTs) alter SARS-CoV-2 mRNA vaccine immunogenicity in patients with autoimmune diseases. Here we investigated the induction and stability of vaccine-specific antibodies,...
Article
Advanced age is a main risk factor for severe COVID-19. However, low vaccination efficacy and accelerated waning immunity have been reported in this age group. To elucidate age-related differences in immunogenicity, we analyzed human cellular, serological, and salivary SARS-CoV-2 spike glycoprotein-specific immune responses to the BNT162b2 COVID-19...
Preprint
Full-text available
Advanced age is a main risk factor for severe COVID-19 and thus elderly were often prioritized for vaccination. However, low vaccination efficacy and accelerated waning immunity have been reported in this age group. To elucidate age-related differences in immunogenicity, we analysed cellular, serological and salivary SARS-CoV-2 spike glycoprotein-s...
Article
Full-text available
Flow cytometers are robust and ubiquitous tools of biomedical research, as they enable high-throughput fluorescence-based multi-parametric analysis and sorting of single cells. However, analysis is often constrained by the availability of detection reagents or functional changes of cells caused by fluorescent staining. Here, we introduce MAPS-FC (m...
Article
Full-text available
The functional relevance of pre-existing cross-immunity to SARS-CoV-2 is a subject of intense debate. Here, we show that human endemic coronavirus (HCoV)-reactive and SARS-CoV-2-cross-reactive CD4 ⁺ T cells are ubiquitous but decrease with age. We identified a universal immunodominant coronavirus-specific spike peptide (S816-830) and demonstrate th...
Article
Full-text available
DNA methylation plays a critical role during development, particularly in repressing retrotransposons. The mammalian methylation landscape is dependent on the combined activities of the canonical maintenance enzyme Dnmt1 and the de novo Dnmts, 3a and 3b. Here, we demonstrate that Dnmt1 displays de novo methylation activity in vitro and in vivo with...
Article
Full-text available
This study elucidates the mechanism of CCL25 and CCR9 in rheumatoid arthritis. RA synovial fluid (SF) expresses elevated levels of CCL25 compared to OA SF and plasma from RA and normal. CCL25 was released into RA SF by fibroblasts (FLS) and macrophages (MΦs) stimulated with IL‐1β and IL‐6. CCR9 is also presented on IL‐1β and IL‐6 activated RA FLS a...
Preprint
Full-text available
While evidence for pre-existing SARS-CoV-2-cross-reactive CD4+ T cells in unexposed individuals is increasing, their functional significance remains unclear. Here, we comprehensively determined SARS-CoV-2-cross-reactivity and human coronavirus-reactivity in unexposed individuals. SARS-CoV-2-cross-reactive CD4+ T cells were ubiquitous, but their pre...
Article
Full-text available
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the rapidly unfolding coronavirus disease 2019 (COVID-19) pandemic1,2. Clinical manifestations of COVID-19 vary, ranging from asymptomatic infection to respiratory failure. The mechanisms determining such variable outcomes remain unresolved. Here, we investigated SARS-CoV-2 spi...
Preprint
Full-text available
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a rapidly unfolding pandemic, overwhelming health care systems worldwide1. Clinical manifestations of Corona-virus-disease 2019 (COVID-19) vary broadly, ranging from asymptomatic infection to acute respiratory failure and death2, yet the underlying physiological conditions...
Article
Full-text available
Background Memory B cell (mBC) induction and maintenance is one of the keys to long-term protective humoral immunity. MBCs are fundamental to successful medical interventions such as vaccinations and therapy in autoimmunity. However, their lifestyle and anatomic residence remain enigmatic in humans. Extrapolation from animal studies serves as a con...
Preprint
Full-text available
This report presents the key concepts of workshop 4 at CYTO 2018 and summarizes the subsequent discussion. The goal of the workshop was to introduce and discuss the use of an LED pulser to characterize the detection performance of flow cytometers.
Poster
Full-text available
A well-defined scale calibration in flow cytometry can improve many aspects of data acquisition such as cytometer setup, instrument comparison and sample comparison. The theory for a light source-based scale calibration was proposed by Steen already in 1992, but it has never been put into regular use due to the lack of a widely available precision...
Article
Full-text available
Oncogenic mutations in KRAS or BRAF are frequent in colorectal cancer and activate the ERK kinase. Here, we find graded ERK phosphorylation correlating with cell differentiation in patient-derived colorectal cancer organoids with and without KRAS mutations. Using reporters, single cell transcriptomics and mass cytometry, we observe cell type-specif...
Article
Mucosal plasma cells (PC) and Ig production are essential to fend pathogens and to maintain mucosal homeostasis. In human Helicobacter pylori infection, mucosal PC express inducible NO synthase (iNOS), which positively correlates with clearance of experimental human infection. To characterize Ig genes and specificities of antral mucosal iNOS+ and i...
Preprint
Full-text available
Mutations activating the KRAS GTPase or the BRAF kinase are frequent in colorectal cancer. Here, we use inducible transgenic expression of KRASG12V or BRAFV600E in intestinal organoids of mice to investigate oncogenic signal transduction in the mitogen-activated protein kinase (MAPK) cascade with cellular resolution. Using phospho-protein, reporter...
Article
There are currently limited insights into the progression of human primary humoral immunity despite numerous studies in experimental models. In this study, we analyzed a primary and related secondary parenteral keyhole limpet hemocyanin (KLH) immunization in five human adults. The primary challenge elicited discordant KLH-specific serum and blood e...
Article
Full-text available
Flow cytometry (FC) is one of the most powerful tools for cell analysis. Recent technical and analytical advances have the potential to revolutionize this technique and may even expand its power for clinical diagnostics. Here, we provide an overview on three of these innovations, namely hyperspectral and multispectral FC, fluorescence minus one con...
Article
Full-text available
A well-defined scale calibration in flow cytometry can improve many aspects of data acquisition such as cytometer setup, instrument comparison and sample comparison. The theory for scale calibration was proposed by Steen over two decades ago, but it has never been put into regular use due to the lack of a widely available precision light source. Th...
Thesis
Gedächtnis-B-Zellen und Plasmazellen sind essentielle Komponenten der protektiven Immunität. Die Mechanismen ihrer Induktion, ihres Überlebens und der Gedächtnis-B-Zellreaktivierung sind allerding bisher nur unvollständig verstanden. Um unser Wissen diesbezüglich zu erweitern, wurden in der vorliegenden Arbeit zum einen Charakteristika von Primär-...
Article
Full-text available
Specific serum antibodies mediating humoral immunity and autoimmunity are provided by mature plasma cells (PC) residing in the bone marrow (BM), yet their dynamics and composition are largely unclear. We here characterize distinct subsets of human PC differing by CD19 expression. Unlike CD19(+) PC, CD19(-) PC were restricted to BM, expressed predom...
Article
Full-text available
Current subunit vaccines are incapable of inducing Ag-specific CD8(+) T cell cytotoxicity needed for the defense of certain infections and for therapy of neoplastic diseases. In experimental vaccines, cytotoxic responses can be elicited by targeting of Ag into cross-presenting dendritic cells (DC), but almost all available systems use target molecu...
Article
Objective: Systemic lupus erythematosus (SLE) is characterized by B cell hyperactivity and autoantibody production. As spleen tyrosine kinase (Syk) is pivotal in B cell activation, these experiments aimed to examine the extent to which Syk was abnormally expressed in SLE B cells and the nature of the B cell subset that differently expressed Syk....
Article
Full-text available
Memory B cells (mBCs) are a key to immunologic memory, yet their distribution within lymphoid organs and the individual role of these for mBC functionality remain largely unknown. This study characterized the distribution and phenotype of human (Ag-specific) mBCs in peripheral blood (PB), spleen, tonsil, and bone marrow. We found that the spleen ha...
Article
Full-text available
Most vaccines confer protection via the elicitation of serum antibodies, yet more than 100 y after the discovery of antibodies, the molecular composition of the human serum antibody repertoire to an antigen remains unknown. Using high-resolution liquid chromatography tandem MS proteomic analyses of serum antibodies coupled with next-generation sequ...
Article
Background Plasma cells (PC) are the unique source of protective and autoreactive immunoglobulin. Mature PC are resting and have downregulated CD20, rendering them refractory to almost all conventional and modern antirheumatic therapies including rituximab. Consequently, the failure to eridacte autoantibody production by plasma cells appears as a t...
Article
Full-text available
Each B-cell receptor consists of a pair of heavy and light chains. High-throughput sequencing can identify large numbers of heavy- and light-chain variable regions (V(H) and V(L)) in a given B-cell repertoire, but information about endogenous pairing of heavy and light chains is lost after bulk lysis of B-cell populations. Here we describe a way to...
Article
Full-text available
Targeting CD74 as the invariant chain of major histocompatibility complexes (MHC) became possible by the availability of a specific humanized monoclonal antibody, milatuzumab, which is under investigation in patients with hematological neoplasms. CD74 has been reported to regulate chemo-attractant migration of macrophages and dendritic cells, while...
Article
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that is known to be associated with polyclonal B-cell hyperreactivity. The underlying causes of the diffuse B-cell over-reactivity are unclear, but potential candidates include (a) intrinsic hyper-reactivity leading to polyclonal B-cell activation with disturbed activation threshol...
Article
B cell depletion therapy with rituximab (anti-CD20) has been established for treating RA. While rituximab efficiently removes circulating B cells, its effects on tissue-based B cells, especially on those in gut-associated lymphoid tissues, remained unclear and are discussed as potential reasons for individual unresponsiveness. Here we studied the f...
Article
Background Epratuzumab, a humanised anti-CD22 monoclonal antibody, is under investigation as a therapeutic antibody in non-Hodgkin's lymphoma and systemic lupus erythematosus (SLE), but its mechanism of action on B cells remains elusive. Treatment of SLE patients with epratuzumab leads to a reduction of circulating CD27negative B cells, although ep...
Article
The anti-CD20 antibody rituximab depletes human B cells from peripheral blood, but it remains controversial to what extent tissue-resident B cells are affected. In representative patients with rheumatoid arthritis, we here demonstrate that recently activated presumably short-lived plasmablasts expressing HLA-DR(high) and Ki-67 continuously circulat...
Article
Full-text available
Epratuzumab, a humanized anti-CD22 monoclonal antibody, is under investigation as a therapeutic antibody in non-Hodgkin's lymphoma and systemic lupus erythematosus (SLE), but its mechanism of action on B-cells remains elusive. Treatment of SLE patients with epratuzumab leads to a reduction of circulating CD27(negative) B-cells, although epratuzumab...
Article
Full-text available
Rechallenge with T cell-dependent Ags induces memory B cells to re-enter germinal centers (GCs) and undergo further expansion and differentiation into plasma cells (PCs) and secondary memory B cells. It is currently not known whether the expanded population of memory B cells and PCs generated in secondary GCs are clonally related, nor has the exten...

Projects

Project (1)
Project
The aim of the project is the full spectral detection of fluorochromes by flow cytometry. Furthermore, the analysis of pulse shapes as generated by a flow cytometer with respect to cells.