Paul David

Dr. Paul David

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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23 September 2022 in Science Advances
Verified
Journal Article
Open access
YCYoung Kwan Cho
Young Kwan Cho
HKHyunho Kim
Hyunho Kim
ABAlan BENARD
Alan BENARD
HWHyun-Kyung Woo
Hyun-Kyung Woo
FCFranziska Czubayko
Franziska Czubayko
HLHakho Lee
Hakho Lee
Electrochemiluminescence (ECL) has an inherently low background and enables precise chemical reactions through electrical control. Here, we report an advanced ECL system, termed ECLipse (ECL in paired signal electrode). We physically separated ECL generation from target detection: These two processes were carried out in isolated chambers and coupled through an electrode. The strategy allowed us to minimize cross-chemical reactions, design electrodes for high ECL signals, and integrate multiple sensors in a chip. As a proof of concept, we implemented an eight-plex ECLipse and applied it to detect host factors in human plasma. ECLipse achieved higher signal-to-noise ratio than conventional ECL assays and was >7000-fold more sensitive than enzyme-linked immunosorbent assay. In a pilot clinical study, we could detect septic conditions by measuring host factors [i.e., interleukin-3 (IL-3), IL-6, and procalcitonin (PCT)]. ECLipse assay further revealed distinct IL-3 and IL-6 patterns in patients with severe acute respiratory syndrome coronavirus 2 infection.

23 March 2023 in Cancers
Verified
Journal Article
Open access
PDF file
PDPaul David
Paul David
AMAnke Mittelstädt
Anke Mittelstädt
DKDina Kouhestani
Dina Kouhestani
AAAnna Anthuber
Anna Anthuber
CKChristoph Kahlert
Christoph Kahlert
GWGeorg Weber
Georg Weber
Worldwide, gastrointestinal (GI) cancers account for a significant amount of cancer-related mortality. Tests that allow an early diagnosis could lead to an improvement in patient survival. Liquid biopsies (LBs) due to their non-invasive nature as well as low risk are the current focus of cancer research and could be a promising tool for early cancer detection. LB involves the sampling of any biological fluid (e.g., blood, urine, saliva) to enrich and analyze the tumor’s biological material. LBs can detect tumor-associated components such as circulating tumor DNA (ctDNA), extracellular vesicles (EVs), and circulating tumor cells (CTCs). These components can reflect the status of the disease and can facilitate clinical decisions. LBs offer a unique and new way to assess cancers at all stages of treatment, from cancer screenings to prognosis to management of multidisciplinary therapies. In this review, we will provide insights into the current status of the various types of LBs enabling early detection and monitoring of GI cancers and their use in in vitro diagnostics.

Verified
Journal Article
Open access
PDF file
FHFrederik Johannes Hansen
Frederik Johannes Hansen
ZWZhiyuan Wu
Zhiyuan Wu
PDPaul David
Paul David
AMAnke Mittelstädt
Anke Mittelstädt
AJAnne Jacobsen
Anne Jacobsen
GWGeorg Weber
Georg Weber
Immunotherapy has become increasingly important in the treatment of colorectal cancer (CRC). Currently, CD73, also known as ecto-5′-nucleotidase (NT5E), has gained considerable interest as a potential therapeutic target. CD73 is one of the key enzymes catalyzing the conversion of extracellular ATP into adenosine, which in turn exerts potent immune suppressive effects. However, the role of CD73 expression on various cell types within the CRC tumor microenvironment remains unresolved. The expression of CD73 on various cell types has been described recently, but the role of CD73 on B-cells in CRC remains unclear. Therefore, we analyzed CD73 on B-cells, especially on tumor-infiltrating B-cells, in paired tumor and adjacent normal tissue samples from 62 eligible CRC patients. The highest expression of CD73 on tumor-infiltrating B-cells was identified on class-switched memory B-cells, followed by naive B-cells, whereas no CD73 expression was observed on plasmablasts. Clinicopathological correlation analysis revealed that higher CD73+ B-cells infiltration in the CRC tumors was associated with better overall survival. Moreover, metastasized patients showed a significantly decreased number of tumor-infiltrating CD73+ B-cells. Finally, neoadjuvant therapy correlated with reduced CD73+ B-cell numbers and CD73 expression on B-cells in the CRC tumors. As promising new immune therapies are being developed, the role of CD73+ B-cells and their subsets in the development of colorectal cancer should be further explored to find new therapeutic options.

5 January 2023 in Cancers
Verified
Journal Article
Open access
PDF file
FHFrederik Johannes Hansen
Frederik Johannes Hansen
PDPaul David
Paul David
MAMarina Akram
Marina Akram
SKSamuel Alfons Christoph Knoedler
Samuel Alfons Christoph Knoedler
AMAnke Mittelstädt
Anke Mittelstädt
GWGeorg Weber
Georg Weber
Pancreatic ductal adenocarcinoma (PDAC) ranks among the most fatal cancer diseases, widely accepted to have the most dismal prognoses. Although immunotherapy has broadly revolutionized cancer treatment, its value in PDAC appears to be relatively low. Exhibiting protumoral effects, monocytes have recently been proposed as potential targets of such immunotherapeutic regimens. However, to date, the body of evidence on monocytes’ role in PDAC is scarce. Therefore, we analyzed monocytes in the peripheral blood of 58 PDAC patients prior to surgery and compared them to healthy individuals. PDAC patients showed increased levels of monocytes when compared to healthy controls In addition, patients with perineural infiltration demonstrated a higher percentage of monocytes compared to non-infiltrating tumors and PDAC G3 was associated with higher monocyte levels than PDAC G2. Patients with monocyte levels > 5% were found to have an 8.9-fold increased risk for a G3 and perineural infiltrated PDAC resulting in poorer survival compared to patients with <5% monocyte levels. Furthermore, PDAC patients showed increased expressions of CD86 and CD11c and decreased expressions of PD-L1 on monocytes compared to healthy individuals. Finally, levels of monocytes correlated positively with concentrations of IL-6 and TNF-α in plasma of PDAC patients. Based on our findings, we propose monocytes as a novel prognostic biomarker. Large-scale studies are needed to further decipher the role of monocytes in PDAC and investigate their potential as therapeutic targets.

Verified
Journal Article
Open access
PDF file
PDPaul David
Paul David
DKDina Kouhestani
Dina Kouhestani
FHFrederik Johannes Hansen
Frederik Johannes Hansen
SPSushmita Paul
Sushmita Paul
FCFranziska Czubayko
Franziska Czubayko
GWGeorg Weber
Georg Weber
The poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is largely due to several challenges, such as late diagnosis, early metastasis, limited response to chemotherapy, aggressive tumor biology, and high rates of tumor recurrence. Therefore, the development of a non-invasive and effective method for early detection of PDAC is crucial to improving patient outcomes. Continued research and exploration in this area are essential to enhance early detection methods and ultimately improve the prognosis for individuals with PDAC. In this study, we examined 37 exosomal surface proteins through a multiplex flow cytometry test on peripheral plasma samples from a group of 51 clinical control individuals (including healthy volunteers and non-cancer patients (Cholecystectomy, Hernia, healthy volunteers)), 21 pancreatitis, and 48 patients diagnosed with PDAC. Our research findings revealed that the level of exosomal CD40 expression is significantly lower in patients with PDAC and pancreatitis compared to non-cancer patients (p < 0.0001). Additionally, pancreatitis patients exhibited higher levels of exosomal CD25 expression than PDAC patients (p = 0.0104). PDAC patients with higher exo-CD40 had worse survival than patients with lower exo-CD40 (p = 0.0035). Similarly, PDAC patients with higher exo-CD25 showed worse survival in comparison to patients with lower exo-CD25 (p = 0.04). Statistical analysis revealed that exosomal CD40 achieved an AUC of 0.827 in distinguishing PDAC from clinical controls. Combining exo-CD40 along with exo-CD25 and CA19-9 discriminated PDAC patients from clinical controls with an AUC of 0.92. Exo-CD40 and exo-CD25 proteins found in exosomes isolated from plasma can serve as excellent non-invasive biomarkers for the early diagnosis of PDAC. Further larger scale studies are needed to validate combined exo-CD40 and exo-CD25 as a diagnostic tool for the identification of PDAC patients through non-invasive liquid biopsy.

1 February 2021 in Expert Review of Proteomics
Verified
Journal Article
Closed access
PDPaul David
Paul David
FHFrederik J. Hansen
Frederik J. Hansen
ABAdil Bhat
Adil Bhat
GWGeorg F. Weber
Georg F. Weber
Introduction: The cytokine storm is a form of excessive systemic inflammatory reaction triggered by a myriad of factors that may lead to multi-organ failure, and finally to death. The cytokine storm can occur in a number of infectious and noninfectious diseases including COVID-19, sepsis, ebola, avian influenza, and graft versus host disease, or during the severe inflammatory response syndrome. Area covered: This review mainly focuses on the most common and well-known methods of protein studies (PAGE, SDS-PAGE, and high- performance liquid chromatography). It also discusses other modern technologies in proteomics like mass spectrometry, soft ionization techniques, cytometric bead assays, and the next generation of microarrays that have been used to get an in-depth understanding of the pathomechanisms involved during the cytokine storm. Expert opinion: Overactivation of leukocytes drives the production and secretion of inflammatory cytokines fueling the cytokine storm. These events lead to a systemic hyper-inflammation, circulatory collapse and shock, and finally to multiorgan failure. Therefore, monitoring the patient’s systemic cytokine levels with proteomic technologies that are redundant, economical, and require minimal sample volume for real-time assessment might help in a better clinical evaluation and management of critically ill patients.