Publications by authors named "Penelope Pelczar"

9 Publications

  • Page 1 of 1

Microbiota-Dependent Effects of IL-22.

Cells 2020 09 29;9(10). Epub 2020 Sep 29.

I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany.

Cytokines are important contributors to immune responses against microbial and environmental threats and are of particular importance at epithelial barriers. These interfaces are continuously exposed to external factors and thus require immune components to both protect the host from pathogen invasion and to regulate overt inflammation. Recently, substantial efforts have been devoted to understanding how cytokines act on certain cells at barrier sites, and why the dysregulation of immune responses may lead to pathogenesis. In particular, the cytokine IL-22 is involved in preserving an intact epithelium, maintaining a balanced microbiota and a functioning defense system against external threats. However, a tight regulation of IL-22 is generally needed, since uncontrolled IL-22 production can lead to the progression of autoimmunity and cancer. Our aim in this review is to summarize novel findings on IL-22 and its interactions with specific microbial stimuli, and subsequently, to understand their contributions to the function of IL-22 and the clinical outcome. We particularly focus on understanding the detrimental effects of dysregulated control of IL-22 in certain disease contexts.
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September 2020

IL22BP Mediates the Antitumor Effects of Lymphotoxin Against Colorectal Tumors in Mice and Humans.

Gastroenterology 2020 10 22;159(4):1417-1430.e3. Epub 2020 Jun 22.

Section of Molecular Immunology und Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. Electronic address:

Background & Aims: Unregulated activity of interleukin (IL) 22 promotes intestinal tumorigenesis in mice. IL22 binds the antagonist IL22 subunit alpha 2 (IL22RA2, also called IL22BP). We studied whether alterations in IL22BP contribute to colorectal carcinogenesis in humans and mice.

Methods: We obtained tumor and nontumor tissues from patients with colorectal cancer (CRC) and measured levels of cytokines by quantitative polymerase chain reaction, flow cytometry, and immunohistochemistry. We measured levels of Il22bp messenger RNA in colon tissues from wild-type, Tnf, Lta, and Ltb mice. Mice were given azoxymethane and dextran sodium sulfate to induce colitis and associated cancer or intracecal injections of MC38 tumor cells. Some mice were given inhibitors of lymphotoxin beta receptor (LTBR). Intestine tissues were analyzed by single-cell sequencing to identify cell sources of lymphotoxin. We performed immunohistochemistry analysis of colon tissue microarrays from patients with CRC (1475 tissue cores, contained tumor and nontumor tissues) and correlated levels of IL22BP with patient survival times.

Results: Levels of IL22BP were decreased in human colorectal tumors, compared with nontumor tissues, and correlated with levels of lymphotoxin. LTBR signaling was required for expression of IL22BP in colon tissues of mice. Wild-type mice given LTBR inhibitors had an increased tumor burden in both models, but LTBR inhibitors did not increase tumor growth in Il22bp mice. Lymphotoxin directly induced expression of IL22BP in cultured human monocyte-derived dendritic cells via activation of nuclear factor κB. Reduced levels of IL22BP in colorectal tumor tissues were associated with shorter survival times of patients with CRC.

Conclusions: Lymphotoxin signaling regulates expression of IL22BP in colon; levels of IL22BP are reduced in human colorectal tumors, associated with shorter survival times. LTBR signaling regulates expression of IL22BP in colon tumors in mice and cultured human dendritic cells. Patients with colorectal tumors that express low levels of IL22BP might benefit from treatment with an IL22 antagonist.
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October 2020

Systemic interleukin 10 levels indicate advanced stages while interleukin 17A levels correlate with reduced survival in esophageal adenocarcinomas.

PLoS One 2020 16;15(4):e0231833. Epub 2020 Apr 16.

Section of Molecular Immunology und Gastroenterology, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.

Introduction: Reflux promotes esophageal adenocarcinomas (EAC) creating a chronic inflammatory environment. EAC show an increasing incidence in the Western World and median survival rates are still low. The main reasons for poor prognosis despite new multimodal therapies are diagnosis of EACs at an already advanced stage and distant metastases. Hence, we wanted to investigate the presence of systemic inflammatory interleukins (IL) and their impact on patient prognosis.

Material And Methods: Systemic expression levels of pro- and anti-inflammatory markers (IL-2, IL-4, IL-6, IL-10, IL-17A and IL-22) in the sera of 43 EAC patients without neoadjuvant radiochemotherapy were measured by flow cytometric analysis. A correlation to clinicopathological data was performed. Log-rank and Cox regression analysis were used to investigate the impact on patient survival. 43 sera of age and gender matched healthy volunteers were used as controls.

Results: Increased systemic IL-6 (p = 0.044) and lower IL-17A (p = 0.002) levels were found in EAC patients as opposed to controls. A correlation of IL-10 levels with an increased T stage was found (p = 0.020). Also, systemic IL-10 levels were highly elevated in patients with distant metastasis (p<0.001). However, only systemic IL-17A levels had an influence on patient survival in multivariate analysis.

Conclusion: Systemic IL-6 levels are increased, while IL-17A levels are reduced in EAC patients compared to healthy controls. In addition, circulating IL-10 might help to identify patients with advanced disease and high IL-17A might indicate a limited prognosis.
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August 2020

Anti-inflammatory microenvironment of esophageal adenocarcinomas negatively impacts survival.

Cancer Immunol Immunother 2020 Jun 25;69(6):1043-1056. Epub 2020 Feb 25.

Section of Molecular Immunology and Gastroenterology, Center of Internal Medicine, I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.

Objective: Reflux promotes esophageal adenocarcinomas (EACs) creating a chronic inflammatory environment. Survival rates are low due to early local recurrences and distant metastasis. Hence, there is a need for new potential treatment options like immunotherapies. However, the inflammatory microenvironment in EACs and its impact on patient outcome remain to be fully understood.

Methods: mRNA expression levels of pro- and anti-inflammatory markers in 39 EAC patients without neoadjuvant radio-chemotherapy were measured. Data were confirmed using flow cytometric analysis of freshly resected surgical specimens. Inflammatory alterations in premalignant lesions of Barrett's esophagus were analyzed by immunohistochemistry.

Results: Expression levels of IL22 were reduced in EAC, while expression levels of FOXP3, IL10 and CTLA4 were increased. Flow cytometry demonstrated a strong infiltration of CD4 T cells with a reduction in CD4 T cells producing IL-22 or IL-17A. We also observed an increase in CD4CD127FOXP3 cells producing IL-10. Accumulation of FOXP3 T cells occurred prior to malignant changes. High expression of IL10 and low expression of IL22 in EAC were associated with reduced overall survival. Moreover, increased expression of IL10, CTLA4 and PD1 in the unaltered esophageal mucosa distant to the EAC was also linked with an unfavorable prognosis.

Conclusion: EAC shows an anti-inflammatory environment, which strongly affects patient survival. The microscopically unaltered peritumoral tissue shows a similar anti-inflammatory pattern indicating an immunological field effect, which might contribute to early local recurrences despite radical resection. These data suggest that using checkpoint inhibitors targeting anti-inflammatory T cells would be a promising therapeutic strategy in EAC.
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June 2020

Regulation of IL-22BP in psoriasis.

Sci Rep 2018 03 23;8(1):5085. Epub 2018 Mar 23.

Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany.

IL-22 is a potent pro-inflammatory cytokine upregulated in psoriasis and in other inflammatory diseases. The function of IL-22 is regulated by the soluble scavenging receptor, IL-22 binding protein (IL-22BP or IL-22RA2). However, the role and regulation of IL-22BP itself in the pathogenesis of inflammatory disease remain unclear. We used the TLR7 agonist Imiquimod (IMQ) to induce a psoriasis-like skin disease in mice and found a strong downregulation of IL-22BP in the affected skin as well as in the lymph nodes of animals treated with IMQ. We also analysed psoriatic skin of patients and compared this to skin of healthy donors. Interestingly, IL-22BP expression was similarly downregulated in skin biopsies of psoriasis patients compared to the skin of healthy donors. Since IL-22BP is expressed foremost in dendritic cells, we characterized its expression in monocyte-derived dendritic cells (MoDC) during maturation. In this way, we found Prostaglandin E2 (PGE) to be a potent suppressor of IL-22BP expression in vitro. We conclude that regulation of IL-22BP by inflammatory mediators is an important step for the progression of inflammation in the skin and possibly also in other autoimmune diseases.
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March 2018

IL-10 Receptor Signaling Is Essential for TR1 Cell Function In Vivo.

J Immunol 2017 02 21;198(3):1130-1141. Epub 2016 Dec 21.

I.Medizinische Klinik, Universitätsklinikum Hamburg-Eppendorf, Hamburg 20246, Germany;

IL-10 is essential to maintain intestinal homeostasis. CD4 T regulatory type 1 (T1) cells produce large amounts of this cytokine and are therefore currently being examined in clinical trials as T cell therapy in patients with inflammatory bowel disease. However, factors and molecular signals sustaining T1 cell regulatory activity still need to be identified to optimize the efficiency and ensure the safety of these trials. We investigated the role of IL-10 signaling in mature T1 cells in vivo. Double IL-10 Foxp3 reporter mice and transgenic mice with impairment in IL-10 receptor signaling were used to test the activity of T1 cells in a murine inflammatory bowel disease model, a model that resembles the trials performed in humans. The molecular signaling was elucidated in vitro. Finally, we used human T1 cells, currently employed for cell therapy, to confirm our results. We found that murine T1 cells expressed functional IL-10Rα. T1 cells with impaired IL-10 receptor signaling lost their regulatory activity in vivo. T1 cells required IL-10 receptor signaling to activate p38 MAPK, thereby sustaining IL-10 production, which ultimately mediated their suppressive activity. Finally, we confirmed these data using human T1 cells. In conclusion, T1 cell regulatory activity is dependent on IL-10 receptor signaling. These data suggest that to optimize T1 cell-based therapy, IL-10 receptor expression has to be taken into consideration.
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February 2017

A pathogenic role for T cell-derived IL-22BP in inflammatory bowel disease.

Science 2016 10;354(6310):358-362

I. Medizinische Klinik und Poliklinik, Universitätsklinikum Hamburg-Eppendorf, 20246 Hamburg, Germany.

Intestinal inflammation can impair mucosal healing, thereby establishing a vicious cycle leading to chronic inflammatory bowel disease (IBD). However, the signaling networks driving chronic inflammation remain unclear. Here we report that CD4 T cells isolated from patients with IBD produce high levels of interleukin-22 binding protein (IL-22BP), the endogenous inhibitor of the tissue-protective cytokine IL-22. Using mouse models, we demonstrate that IBD development requires T cell-derived IL-22BP. Lastly, intestinal CD4 T cells isolated from IBD patients responsive to treatment with antibodies against tumor necrosis factor-α (anti-TNF-α), the most effective known IBD therapy, exhibited reduced amounts of IL-22BP expression but still expressed IL-22. Our findings suggest that anti-TNF-α therapy may act at least in part by suppressing IL-22BP and point toward a more specific potential therapy for IBD.
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October 2016

IL-23 prevents IL-13-dependent tissue repair associated with Ly6C(lo) monocytes in Entamoeba histolytica-induced liver damage.

J Hepatol 2016 May 22;64(5):1147-1157. Epub 2016 Jan 22.

Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany. Electronic address:

Background & Aims: The IL-23/IL-17 axis plays an important role in the pathogenesis of autoimmune diseases and the pathological consequences of infection. We previously showed that immunopathologic mechanisms mediated by inflammatory monocytes underlie the severe focal liver damage induced by the protozoan parasite, Entamoeba histolytica. Here, we analyze the contribution of the IL-23/IL-17 axis to the induction and subsequent recovery from parasite-induced liver damage.

Methods: IL-23p19(-/-), IL-17A/F(-/-), CCR2(-/-), and wild-type (WT) mice were intra-hepatically infected with E. histolytica trophozoites and disease onset and recovery were analyzed by magnetic resonance imaging. Liver-specific gene and protein expression during infection was examined by qPCR, microarray, FACS analysis and immunohistochemistry. Immuno-depletion and substitution experiments were performed in IL-23p19(-/-) and WT mice to investigate the role of IL-13 in disease outcome.

Results: Liver damage in infected IL-23p19(-/-), IL-17A/F(-/-), and CCR2(-/-) mice was strongly attenuated compared with that in WT mice. IL-23p19(-/-) mice showed reduced accumulation of IL-17 and CCL2 mRNA and proteins. Increased numbers of IL-13-producing CD11b(+)Ly6C(lo) monocytes were associated with disease attenuation in IL-23p19(-/-) mice. Immuno-depletion of IL-13 in IL-23p19(-/-) mice reversed this attenuation and treatment of infected WT mice with an IL-13/anti-IL-13-mAb complex supported liver recovery.

Conclusions: The IL-23/IL-17 axis plays a critical role in the immunopathology of hepatic amebiasis. IL-13 secreted by CD11b(+)Ly6C(lo) monocytes may be associated with recovery from liver damage. An IL-13/anti-IL13-mAb complex mimics this function, suggesting a novel therapeutic option to support tissue healing after liver damage.
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May 2016

Inactivation of Patched1 in mice leads to development of gastrointestinal stromal-like tumors that express Pdgfrα but not kit.

Gastroenterology 2013 Jan 3;144(1):134-144.e6. Epub 2012 Oct 3.

Department of Human Genetics, University Medical Center, Göttingen, Germany.

Background & Aims: A fraction of gastrointestinal stromal tumor (GIST) cells overexpress the platelet-derived growth factor receptor (PDGFR)A, although most overexpress KIT. It is not known if this is because these receptor tyrosine kinases have complementary oncogenic potential, or because of heterogeneity in the cellular origin of GIST. Little also is known about why Hedgehog (HH) signaling is activated in some GIST. HH binds to and inactivates the receptor protein patched homolog (PTCH).

Methods: Ptch was conditionally inactivated in mice (to achieve constitutive HH signaling) using a Cre recombinase regulated by the lysozyme M promoter. Cre-expressing cells were traced using R26R-LacZ reporter mice. Tumors were characterized by in situ hybridization, immunohistochemistry, immunoblot, and quantitative reverse-transcriptase polymerase chain reaction analyses. Cell transformation was assessed by soft agar assay.

Results: Loss of Ptch from lysozyme M-expressing cells resulted in the development of tumors of GIST-like localization and histology; these were reduced when mice were given imatinib, a drug that targets KIT and PDGFRA. The Hh signaling pathway was activated in the tumor cells, and Pdgfrα, but not Kit, was overexpressed and activated. Lineage tracing revealed that Cre-expressing intestinal cells were Kit-negative. These cells sometimes expressed Pdgfrα and were located near Kit-positive interstitial cells of Cajal. In contrast to KIT, activation of PDGFRA increased anchorage-independent proliferation and was required for tumor formation in mice by cells with activated HH signaling.

Conclusions: Inactivation of Ptch in mice leads to formation of GIST-like tumors that express Pdgfrα, but not Kit. Activation of Pdgfrα signaling appears to facilitate tumorigenesis.
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January 2013