Podcasts about ccr4

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Latest podcast episodes about ccr4

Aging-US
CCR4-NOT Complex in Stress Resistance and Longevity in C. elegans

Aging-US

Play Episode Listen Later Jun 11, 2024 3:52


BUFFALO, NY- June 11, 2024 – A new editorial paper was published in Aging (listed by MEDLINE/PubMed as "Aging (Albany NY)" and "Aging-US" by Web of Science) Volume 16, Issue 10, entitled, “CCR4-NOT complex in stress resistance and longevity in C. elegans.” The ability to mount an adaptive response to environmental stress is crucial in organismal survival and overall fitness. In the context of aging, many genes that mediate resistance to stressors are also important in longevity, and aging has been shown to cause a decline in stress resistance. In their new editorial, researchers Cheng-Wei Wu and Hadi Tabarraei from the University of Saskatchewan wrote that recently, during a screening for genes that are required for the transcriptional response to heavy metal and oxidative stress in C. elegans, they found that depletion of subunits within the evolutionarily conserved CCR4-NOT protein complex compromises stress resistance and decreases lifespan. “The CCR4-NOT (Carbon Catabolite Repression 4 – Negative On TATA-less) is a multi-protein complex tasked with regulating RNA metabolism across multiple steps including mRNA decay, transcription initiation and elongation, mRNA quality control and export, and mRNA translatability (reviewed in [3]).” Studies in yeast have shown that CCR4-NOT is required for transcriptional elongation of stress responsive genes and that loss of function mutants of this protein complex have increased sensitivity to replication stress caused by DNA damaging agents [4, 5]. An expansive role for the CCR4-NOT complex in stress-induced transcriptional programming was demonstrated in C. elegans via whole-transcriptome sequencing analysis [2]. “Together, while the CCR4-NOT complex has been extensively studied for the past 3 decades, new studies in the model organism C. elegans have revealed an important new role for this protein complex in regulating normal aging as well as a requirement for many well-characterized and evolutionarily conserved pro-longevity pathways including reduced insulin signaling, mitochondrial suppression, enhanced stress response, and dietary restriction.” DOI - https://doi.org/10.18632/aging.205918 Corresponding author - Cheng-Wei Wu - michael.wu@usask.ca Video short - https://www.youtube.com/watch?v=UFi7Dq5JXJ4 Sign up for free Altmetric alerts about this article - https://aging.altmetric.com/details/email_updates?id=10.18632%2Faging.205918 Subscribe for free publication alerts from Aging - https://www.aging-us.com/subscribe-to-toc-alerts Keywords - aging, oxidative stress, C. elegans, CCR4-NOT About Aging-US Aging publishes research papers in all fields of aging research, including but not limited to aging processes (from yeast to mammals), cellular senescence, age-related diseases (such as cancer and Alzheimer's disease) and their prevention and treatment, anti-aging strategies and drug development, and, importantly, the role of signal transduction pathways in aging (such as mTOR) and potential approaches to modulate these signaling pathways to extend lifespan. The journal aims to promote 1) treatment of age-related diseases by slowing down aging, 2) validation of anti-aging drugs by treating age-related diseases, and 3) prevention of cancer by inhibiting aging. (Cancer and COVID-19 are age-related diseases.). Please visit our website at https://www.Aging-US.com​​ and connect with us: Facebook - https://www.facebook.com/AgingUS/ X - https://twitter.com/AgingJrnl Instagram - https://www.instagram.com/agingjrnl/ YouTube - https://www.youtube.com/@AgingJournal LinkedIn - https://www.linkedin.com/company/aging/ Pinterest - https://www.pinterest.com/AgingUS/ Spotify - https://open.spotify.com/show/1X4HQQgegjReaf6Mozn6Mc MEDIA@IMPACTJOURNALS.COM

Blood Podcast
Overcoming CAR T cell resistance in myeloma, why anti-CCR4 antibody therapy in CTCL sometimes fails, and corticosteroids increase risk of VOE in sickle disease

Blood Podcast

Play Episode Listen Later Jun 30, 2022 19:07


In this week's episode we review a novel strategy for overcoming resistance to CAR T cell therapy that involves the dual targeting of myeloma cells and cancer-associated fibroblasts. We'll also explore a recent report demonstrating that loss of CCR4 expression is common after treatment of CTCL with the anti-CCR4 antibody mogamulizumab. Finally, we'll review real-world data demonstrating an association between corticosteroid exposure and risk of vaso-occlusive episodes in patients with sickle cell disease, providing further evidence that steroids should be avoided in this setting.

Journal of Clinical Oncology (JCO) Podcast
Keeping Mycosis Fungoides in Check: A Study of Pembrolizumab for Relapsed/Refractory MF and Sezary Syndrome

Journal of Clinical Oncology (JCO) Podcast

Play Episode Listen Later Jan 6, 2020 9:04


This podcast evaluates results from a phase II clinical trial of pembrolizumab for relapsed Mycosis Fungoides and Sezary Syndrome in the context of the current systemic treatment landscape for this disease. TRANSCRIPT This JCO Podcast provides observations and commentary on the JCO article "Pembrolizumab in Relapsed and Refractory Mycosis Fungoides and Sezary Syndrome: A Multicenter Phase II Study" by Khodadoust et al. My name is Jennifer Amengual, and I am an Assistant Professor of Medicine at the Columbia University Irving Medical Center in New York, New York, USA. My oncologic specialty is lymphoma. Mycosis fungoides, otherwise known as MF, and Sezary Syndrome, its leukemic variant, are rare subtypes of cutaneous T-cell lymphoma. Although most patients with MF have indolent disease, those with advanced stage MF often experience resistance to systemic therapy with a persistent and progressive disease course, which has a negative impact on overall well-being and survival. Patients may have intense pruritus, which can then put them at increased risk for staphylococcus infection, sepsis and in turn can trigger disease flare. Advanced-stage MF is a chronic disease that is not considered curable; therefore, it is necessary to consider management strategies that provide symptom relief and can be maintained over a long period of time. Most patients cycle through a multitude of therapies, often including skin-directed and, later, systemic therapies. Many of the acceptable therapies are derived from retrospective studies or single-arm trials; therefore, it is not possible to objectively compare outcomes and toxicity. In order to put the outcomes of pembrolizumab in context of other acceptable treatment modalities, I will discuss some of these treatments now. Systemic retinoids, such as bexarotene, are taken orally and can induce an overall response of 45-55%. The drug is well tolerated but can lead to hypertriglyceridemia and hypothyroidism, requiring monthly monitoring and frequent treatment with lipid-lowering agents and thyroid hormone replacement. Low-dose methotrexate, administered either orally or by intravenous infusion weekly, can lead to response rates between 30 and 50%. Common side-effects include mucositis, cytopenias and gastrointestinal upset. Pralatrexate is a novel antifolate drug that when studied using half the dose of that which is approved for PTCL , induced a 45% response rate for patients with MF. The treatment is also well tolerated, with the most common side-effects being mucositis and thrombocytopenia. There are 2 histone deacetylase inhibitors approved for use in MF and Sezary Syndrome. Both romidepsin and vorinostat have overlapping toxicity profiles, including gastrointestinal disturbances, fatigue, anorexia, and cytopenias. Romidepsin is also associated with ECG abnormalities. In patients with cutaneous T cell lymphoma, romidepsin has demonstrated a response rate of 34% and is associated with a median duration of response of 15 months. Vorinostat, an oral drug, has demonstrated a response rate of 30%. Recently, 2 biologics have been in used for patients with MF. Brentuximab vedotin is an antibody drug conjugate which targets the surface marker CD30 and brings monomethyl auristatin E into the cell. It is associated with a response rate of 70% in MF. Responses are significantly better in those with greater than 5% of CD30 expression. The most common side-effect is peripheral neuropathy. Mogamulizumab is a humanized antibody directed against the chemokine receptor CCR4.  This agent was studied in a randomized trial compared to vorinostat, where it led to a PFS of 7.7 months and response rate of 28%. The most common adverse events were attributed to infusion reactions, rash, diarrhea, and fatigue. There was also an increased risk of graft-versus-host disease in patients who subsequently went on to allogenic transplant, which needs to be considered when using this treatment strategy. As you can see, there are many different approaches to the treatment of advanced-stage MF and Sezary Syndrome, and the drugs I have discussed do not encompass an exhaustive list. Immune checkpoint antibodies against Programmed cell death protein 1 otherwise known as PD-1 interfere with inhibitory signaling pathways expressed on exhausted T-cells and wake up these cells allowing them to perform anti-tumor activities. The investigators rationalize the use of PD-1 inhibitors in MF and Sezary syndrome given PD-1 dysfunction and altered expression on MF cells and  the skin microenvironment. The Cancer Immunotherapy Trials Network performed a multicenter phase II single-arm study of pembrolizumab in 24 patients across 8 centers with relapsed or refractory MF or Sezary Syndrome. Of the 24 patients enrolled, 9 had MF and 15 had Sezary syndrome. Most had advanced disease represented by tumor stage disease, erythrodermic presentation, or were stage IIIB or higher. Patients received a median of 4 prior lines of systemic therapy. In addition, 4 patients had evidence of histologic large cell transformation. These represent some of the most challenging clinical situations. Pembrolizumab was administered every 3 weeks for 24 months or until withdrawal of consent, adverse reactions or investigator’s decision. The therapy was well tolerated, with no grade 4 or 5 immune-related adverse events. There were, however, 11 immune-related adverse events observed among 9 patients. This led to discontinuation of treatment in 4 patients, all due to grade 3 events including pneumonitis, duodenitis, hepatitis, and a corneal ulcer. Interestingly, over half of the patients with Sezary Syndrome experienced a flare of their symptoms early in their treatment course. This manifested as increased erythema, pruritus, and peripheral edema. Patients were managed with topical steroids and close observation. Only 1 patient had a prolonged reaction requiring systemic therapy, and no patients were discontinued from therapy due to flare of their disease. Patients with MF did not experience any skin toxicity. The authors investigated the relationship of this reaction to response and found that 3 of 8 Sezary patients who experienced a skin flare went on to achieve a response, whereas only 1 of the 7 Sezary patients who did not have a flare achieved a response. Using mass cytometry profiling of PBMCs, the authors observed a sevenfold increase in PD-1 expression on circulating Sezary cells in patients who experienced a flare. Although these observations were made across a small number of patients, it will be worthwhile to pay attention to this in future studies to determine if this is a true predictor for flare reaction or response. Pembrolizumab demonstrated significant clinical responses in 9 of 24 patients, leading to an overall response rate of 38%. This falls right into the range with other acceptable treatment options. Patients were heavily pretreated, yet the number of prior lines of therapy did not impact the response to pembrolizumab, possibly owing to non-overlapping mechanism of action. In addition, responses were seen in both MF and Sezary patients and those with erythrodermic and tumor stage presentations. There was a trend toward better outcomes in the MF patients. Responses were durable, and the median duration was not reached within a follow-up period of 58 weeks. The 1-year PFS was 65%, and OS was 95%. Two responding patients relapsed 8 to 12 weeks after discontinuation of treatment. The authors discuss that this may indicate the need for continuous treatment in this patient population, which is contrary to the general treatment strategy used for checkpoint inhibitors in other malignancies. Although this study only enrolled 24 patients, pembrolizumab appears to have similar outcomes as other drugs used in advanced-stage MF and Sezary Syndrome, with an acceptable toxicity profile. It produces a long duration of response, making it an attractive addition for patients suffering from this disease. Pembrolizumab does not have overlapping mechanism of action with most of the drugs used today and can therefore be easily integrated into the sequence of treatment for patients with MF and Sezary Syndrome. Finally, it is possible that pembrolizumab’s effects will enhance those seen with other agents. We should look forward to confirmatory clinical trials of pembrolizumab for the management of patients with MF or Sezary Syndrome. This concludes this JCO Podcast. Thank you for listening.

WCCS 2016
Treatment of cutaneous T cell lymphoma

WCCS 2016

Play Episode Listen Later Aug 11, 2017 3:21


Dr Duvic speaks with ecancertv at WCCS 2016 about mogamulizumab, an anti-CCR4 engineered antibody for treatment of cutaneous T cell lymphoma, also known as Sézary syndrome She reports on results from a phase I/II trial in which patient response rate reached 37%, and describes upcoming trials for mogamulizumab, with considerations of international approval and possible combination/complementary therapies.

AACR 2016
Targeting T regs in tumours

AACR 2016

Play Episode Listen Later Aug 11, 2017 6:50


Dr Dario Vignali speaks with ecancertv at AACR 2016 about his work with regulatory T cells, an essential part of innate immunity but also modulated within the tumour microenvironment. Looking beyond current checkpoint inhibitory research, he describes T regs as a promising avenue for further investigation, such as ongoing trials of mogamulizumab, a CCR4 antibody. Considering wide interest in immunotherapy, especially as combination therapies, Dr Vignali describes the potential impact of understanding T regs on numerous aspects of medicine.

Fakultät für Chemie und Pharmazie - Digitale Hochschulschriften der LMU - Teil 05/06
Structural and biochemical characterization of the c-terminal module of the yeast Ccr4-Not complex

Fakultät für Chemie und Pharmazie - Digitale Hochschulschriften der LMU - Teil 05/06

Play Episode Listen Later Apr 21, 2015


mRNA turnover begins with deadenylation wherein the poly(A) tail at the 3’ end of the mRNA is enzymatically removed. Deadenylation also happens to be the rate-limiting step of the decay pathway. In vivo, deadenylation is carried out by two macromolecular complexes, namely the Pan2-Pan3 complex and the Ccr4-Not complex. The Ccr4-Not complex is a multi-protein complex that is evolutionarily conserved in all eukaryotes and is considered as the major deadenylase complex in the cell. In S. cerevisiae, the Ccr4-Not complex is composed of nine subunits and is built around the scaffolding protein Not1. Structurally, the Ccr4-Not complex assembles into four separate modules with distinct domains of Not1 acting as a scaffold for individual modules. The four modules include the N-terminal module, the deadenylase module, the Caf40 module and the C-terminal module. With the exception of the C-terminal module, the architecture and biochemical role of all other modules of the yeast Ccr4-Not complex has been characterized. My doctoral thesis is focused on the elucidation of the architecture of the C- terminal module of the yeast Ccr4-Not complex. The C-terminal module can be divided in to two sub-modules, the Not module and the ubiquitylation module. The Not module is composed of the C- terminal domain of the Not1, the Not2 and the Not5 proteins in S. cerevisiae. Using limited proteolysis, the minimal core of the Not module was identified to be formed of the C-terminal domain Not1 (Not1C), full-length Not2 and the C- terminal domain of Not5 (Not5C). The minimal core of the Not module was reconstituted, crystallized and the structure was determined at 2.8 Å resolution. The structure reveals that Not1C adopts a HEAT repeat architecture with 10 HEAT repeats. The C-terminal Not-box domains of Not2 and Not5 adopt a Sm-like fold and heterodimerize via a non-canonical dimerization interface. This heterodimerization of Not2 and Not5 brings their N-terminal extended regions in proximity to each other. The N-terminal extended regions of Not2 and Not5 interact with Not1C synergistically. Loss of Not1 interacting region of either Not2 or Not5 leads to complete disassembly of the Not module in vitro and in vivo. Analysis of the electrostatic surface potential of the Not1C-Not2-Not5C crystal structure shows the presence of a positive patch on the surface. Using biochemical assays and cross-linking mass-spectrometry approaches, the RNA binding properties of the Not module were explored. The Not module binds specifically to poly(U) RNA with a major site on the Not-box domain of Not5. The ubiquitylation module consists of the C-terminal domain of Not1 and Not4. Not4 harbors a N-terminal RING domain with E3 ubiquitin ligase activity and a C-terminal low-complexity region essential for its association with the Ccr4-Not complex. I characterized distinct regions of yeast Not4 structurally and biochemically, with their respective interaction partners. First, the crystal structure of the RING domain of Not4 in complex with the Ubc4 was determined. Ubc4 is the cognate E2 enzyme of the Not4 E3 ligase. The structure of the E2-E3 complex provided insights into the specificity of Ubc4 towards Not4. Second, the minimal Not1 interacting region of Not4 was mapped and the minimal core of the Not1-Not4 complex was crystallized. Analysis of the crystal structure of Not1C in complex with the minimal interacting region of Not4 (Not4C) identified a yeast specific short linear motif in Not4c that is essential for Not1 binding. Thus, the structure provides insights into the putative differences between yeast Not4 and its homologues from higher eukaryotes that highlight the differences in the complex formation property. In brief, my doctoral thesis provides insights into the architecture of the Not module and the ubiquitylation module of the Ccr4-Not complex. Together, these results present a structural model for the C-terminal arm of the yeast Ccr4-Not complex and also provide insights into how the C-terminal module contributes to mRNA and protein degradation.

Medizinische Fakultät - Digitale Hochschulschriften der LMU - Teil 17/19
Phenotypic characterization of CCR2+ T cells in experimental pulmonary fibrosis

Medizinische Fakultät - Digitale Hochschulschriften der LMU - Teil 17/19

Play Episode Listen Later Dec 18, 2014


Interstitial lung diseases (ILD) are severe chronic lung diseases characterized by an increased deposition of extracellular matrix in the lung interstitial space, leading to a thickening of the alveolar walls and impairment of the gas exchange. One of the most common entities in this category is idiopathic pulmonary fibrosis (IPF) with a mean survival time of 2 to 3 years from diagnosis. Until now, there is no curative therapy available and the symptomatic anti- inflammatory treatment and oxygen supplementation cannot prevent the development of the end stage pulmonary fibrosis. The chemokine receptor CCR2 is important for leukocyte recruitment to inflamed tissues through interaction with CCL2 (MCP-1). The blockade of the CCR2/CCL2 pathway attenuated the development of pulmonary fibrosis in mouse models. However, CCR2+ T-lymphocytes acquired regulatory functions in experimental arthritis during the course of disease. Therefore, it is unknown whether CCR2+ T cells are involved in the pathogenesis of IPF or, on the contrary, represent an unsuccessful effort of the immune system to limit the disease. Observations in paediatric patients with different forms of ILDs suggested a role for CCR2+ T cells in pulmonary fibrosis. To characterize these T cells, flow cytometric studies were performed using the bleomycin mouse model of pulmonary fibrosis. The kinetic of CCR2+ T cells in BALF, lung tissue, and spleen following intratracheal administration of bleomycin (BLM) was assessed at time points between day 3 and day 21. To determine, if the constellation of naïve, central memory and effector memory T cells changes after BLM treatment, and to which of these subtypes CCR2+ T cells belong to, the cells were additionally stained for CD62L and CD44. For further characterization of CCR2+ T cells, chemokine receptor co-expression with CCR2 was investigated at the time point of the maximal presence of CCR2+ T cells. Total T cell numbers increased in BAL and lung tissue but not in spleen. Percentages of CD62LlowCD44hi effector memory T cells increased in lung tissue in the early phase of BLM induced fibrosis, while the CD62LhiCD44low naïve T cell population decreased. The percentage of CCR2+ T cells increased following BLM treatment with a maximum on day 12. The majority of CCR2+CD4+ T cells showed a Tem phenotype. CCR3, CCR4, CCR6, CXCR4, and CXCR5 expressing cells increased within the pulmonary CD4+ T cell population following bleomycin treatment. Among CD8+ T cells from treated mice, CCR5, CCR6, and CXCR5 positive cells were increased. CCR7 was highly co-expressed with CCR2 in saline and bleomycin treated mice, whereas co-expression of CCR3, CCR4, CCR6 and CXCR5 increased significantly in treated mice. The results indicate an activation of pulmonary T cell populations following bleomycin treatment. CCR2+CD4+ T cells probably take part on this T cell response as they exhibit an effector memory phenotype and increase following BLM treatment. In contrast, the stable percentages of the different T cell subtypes in spleens gave no hint for a systemic T cell reaction. The pattern of chemokine receptor expression argues against a Th1 polarization and towards a Th2, Th17 or TFH polarization of CCR2+ T cells.

Flash Pulp - The Skinner Co. Network
CCR4 – Attack of the Giant Leeches

Flash Pulp - The Skinner Co. Network

Play Episode Listen Later Dec 15, 2014 35:41


We're gathered this evening to consider 1959's Attack of the Giant Leeches, an American International Pictures flick.

The Skinner Co. Network
CCR4 – Attack of the Giant Leeches

The Skinner Co. Network

Play Episode Listen Later Dec 15, 2014 35:41


We're gathered this evening to consider 1959's Attack of the Giant Leeches, an American International Pictures flick.

The Skinner Co. Network
CCR4 – Attack of the Giant Leeches

The Skinner Co. Network

Play Episode Listen Later Dec 15, 2014 35:41


We're gathered this evening to consider 1959's Attack of the Giant Leeches, an American International Pictures flick.

Chrononaut Cinema Reviews - a Skinner Co.\Way of the Buffalo Co-Production

We're gathered this evening to consider 1959’s Attack of the Giant Leeches, an American International Pictures flick.

Medizin - Open Access LMU - Teil 17/22
Cord blood Vα24-Vβ11 natural killer T cells display a Th2-chemokine receptor profile and cytokine responses

Medizin - Open Access LMU - Teil 17/22

Play Episode Listen Later Jan 1, 2011


Background: The fetal immune system is characterized by a Th2 bias but it is unclear how the Th2 predominance is established. Natural killer T (NKT) cells are a rare subset of T cells with immune regulatory functions and are already activated in utero. To test the hypothesis that NKT cells are part of the regulatory network that sets the fetal Th2 predominance, percentages of Vα24(+)Vβ11(+) NKT cells expressing Th1/Th2-related chemokine receptors (CKR) were assessed in cord blood. Furthermore, IL-4 and IFN-γ secreting NKT cells were quantified within the single CKR(+) subsets. Results: Cord blood NKT cells expressed the Th2-related CCR4 and CCR8 at significantly higher frequencies compared to peripheral blood NKT cells from adults, while CXCR3+ and CCR5+ cord blood NKT cells (Th1-related) were present at lower percentages. Within CD4negCD8neg (DN) NKT cells, the frequency of IL-4 producing NKT cells was significantly higher in cord blood, while frequencies of IFN-γ secreting DN NKT cells tended to be lower. A further subanalysis showed that the higher percentage of IL-4 secreting DN NKT cells was restricted to CCR3+, CCR4+, CCR5+, CCR6+, CCR7+, CCR8+ and CXCR4+ DN subsets in cord blood. This resulted in significantly decreased IFN-γ /IL-4 ratios of CCR3+, CCR6+ and CCR8+ cord blood DN NKT cells. Sequencing of VA24AJ18 T cell receptor (TCR) transcripts in sorted cord blood Vα24Vβ11 cells confirmed the invariant TCR alpha-chain ruling out the possibility that these cells represent an unusual subset of conventional T cells. Conclusions: Despite the heterogeneity of cord blood NKT cells, we observed a clear Th2-bias at the phenotypic and functional level which was mainly found in the DN subset. Therefore, we speculate that NKT cells are important for the initiation and control of the fetal Th2 environment which is needed to maintain tolerance towards self-antigens as well as non-inherited maternal antigens.

Journal Club Imunoterapia Tumoral
Edição#23: Antagonistas de CCR7 em células T reguladoras

Journal Club Imunoterapia Tumoral

Play Episode Listen Later Jan 8, 2009 8:31


Nesta edição discuto o artigo publicado por Bayry e colaboradores no jornal PNAS, vol 105 de 2008. Neste artigo, antagonistas do receptor de quimiocinas CCR4 modelizados in silico foram testados in vitro e in vivo com o objectivo de inibirem a actividade imunosupressiva das células T reguladoras.

neste vivo vitro pnas ratinho reguladoras ccr4 ccr7
Medizin - Open Access LMU - Teil 15/22
A complex pattern of chemokine receptor expression is seen in osteosarcoma

Medizin - Open Access LMU - Teil 15/22

Play Episode Listen Later Jan 1, 2008


Background: Osteosarcoma is the most frequent bone tumor in childhood and adolescence. Patients with primary metastatic disease have a poor prognosis. It is therefore important to better characterize the biology of this tumor to define new prognostic markers or therapeutic targets for tailored therapy. Chemokines and their receptors have been shown to be involved in the development and progression of malignant tumors. They are thought to be active participants in the biology of osteosarcoma. The function of specific chemokines and their receptors is strongly associated with the biological context and microenvironment of their expression. In this report we characterized the expression of a series of chemokine receptors in the complex environment that defines osteosarcoma. Methods: The overall level of chemokine receptor mRNA expression was determined using TaqMan RT-PCR of microdissected archival patient biopsy samples. Expression was then verified at the protein level by immunohistochemistry using a series of receptor specific antibody reagents to elucidate the cellular association of expression. Results: Expression at the RNA level was found for most of the tested receptors. CCR1 expression was found on infiltrating mononuclear and polynuclear giant cells in the tumor. Cells associated with the lining of intratumoral vessels were shown to express CCR4. Infiltrating mononuclear cells and tumor cells both showed expression of the receptor CCR5, while CCR7 was predominantly expressed by the mononuclear infiltrate. CCR10 was only very rarely detected in few scattered infiltrating cells. Conclusion: Our data elucidate for the first time the cellular context of chemokine receptor expression in osteosarcoma. This is an important issue for better understanding potential chemokine/chemokine receptor function in the complex biologic processes that underlie the development and progression of osteosarcoma. Our data support the suggested involvement of chemokines and their receptors in diverse aspects of the biology of osteosarcoma, but also contradict aspects of previous reports describing the expression of these receptors in this tumor.

Medizinische Fakultät - Digitale Hochschulschriften der LMU - Teil 06/19
Chemokine und Chemokinrezeptor-exprimierende T-Zellen in bronchoalveolärer Lavage bei interstitiellen Lungenerkrankungen im Vergleich zu chronischer Bronchitis und malignen Erkrankungen der Lunge

Medizinische Fakultät - Digitale Hochschulschriften der LMU - Teil 06/19

Play Episode Listen Later Apr 19, 2007


In der vorliegenden Arbeit wurde bronchoalveolären Lavage Flüssigkeit (BALF) von Patienten mit interstitiellen Lungenerkrankungen (23 Patienten) auf Chemokinkonzentrationen und Chemokinrezeptorexressionsmuster der Lymphozyten analysiert und die Ergebnisse mit Patienten, die an chronischer Bronchitis (6 Patienten) oder malignen Erkrankungen (9 Patienten) der Lunge erkrankt waren verglichen. Mittels ELISA wurden die Chemokinkonzentrationen und mittels Durchflusszytometrie der Anteil an Chemokinrezeptor-exprimierenden T-Zellen in der BALF bestimmt. Hierbei wurden die Chemokinkonzentrationen von MCP 1, TARC, MDC und RANTES und die Häufigkeit CCR2+, CCR5+, CCR4+ und CXCR3+ Zellen innerhalb der CD4+ und CD8+ T-Zellpopulationen gemessen. Es konnte gezeigt werden, dass bei interstitiellen Lungenerkrankungen im Vergleich zu den Kontrollgruppen die MCP-1 Konzentration knapp signifikant (p = 0,055) und die CCR2+CD4+T-Zellen signifikant erhöht waren. Im Zusammenhang mit Daten aus Kinder- und Erwachsenenstudien, in denen in der bronchoalveolären Lavageflüssigkeit erhöhte MCP-1 Werte und vermehrt CCR2+ T-Zellen nachgewiesen wurden, legen diese Ergebnisse eine wichtige Rolle der MCP 1/CCR2-Achse in der Pathogenese der interstitiellen Lungenerkrankungen nahe. Ebenso fanden sich bei interstitiellen Lungenerkrankungen signifikant mehr der TH2-assoziierten CCR4+ T-Zellen; bei dem TH1-assoziierten Rezeptor CXCR3+ ergab sich kein Unterschied. Gemeinsam mit ähnlichen Ergebnissen einiger Studien in Mausmodellen und humanen Studien weisen sie auf eine TH2-Polarisierung der T Zellen bei interstitiellen Lungenerkrankungen hin, welche hierbei einen profibrotischen Effekt haben sollen. Gleichzeitig konnten bei interstitiellen Lungenerkrankungen signifikant mehr CCR5+CD4+ und CCR5+CD8+ Zellen als in den Kontrollgruppen nachgewiesen werden. Da auch bei gesunden Menschen CCR5+ T-Zellen nachgewiesen werden konnten, postulieren wir, dass CCR5+ T-Zellen auch unabhängig von der Polarisierung der T-Zellen ein regulärer Bestandteil des bronchoalveolären Raumes im Rahmen einer normalen Immunreaktion sind. Insgesamt hat diese explorative Analyse aufgezeigt, dass sowohl die MCP 1/CCR2-Achse, als auch TH2-polarisierte T-Zellen ein potentielles Angriffsziel in der Behandlung interstitieller Lungenerkrankungen darstellen könnten. Die Ergebnisse sollten den Anstoß für ausführlichere Untersuchungen mit einem wesentlich größeren Patientenkollektiv geben.

Medizin - Open Access LMU - Teil 14/22
A role for MCP-1/CCR2 in interstitial lung disease in children

Medizin - Open Access LMU - Teil 14/22

Play Episode Listen Later Jan 1, 2005


Background: Interstitial lung diseases (ILD) are chronic inflammatory disorders leading to pulmonary fibrosis. Monocyte chemotactic protein 1 (MCP-1) promotes collagen synthesis and deletion of the MCP-1 receptor CCR2 protects from pulmonary fibrosis in ILD mouse models. We hypothesized that pulmonary MCP-1 and CCR2(+) T cells accumulate in pediatric ILD and are related to disease severity. Methods: Bronchoalveolar lavage fluid was obtained from 25 children with ILD and 10 healthy children. Levels of pulmonary MCP-1 and Th1/Th2-associated cytokines were quantified at the protein and the mRNA levels. Pulmonary CCR2(+), CCR4(+), CCR3(+), CCR5(+) and CXCR3(+) T cells were quantified by flow-cytometry. Results: CCR2(+) T cells and MCP-1 levels were significantly elevated in children with ILD and correlated with forced vital capacity, total lung capacity and ILD disease severity scores. Children with lung fibrosis had significantly higher MCP-1 levels and CCR2(+) T cells in bronchoalveolar lavage fluid compared to non-fibrotic children. Conclusion: The results indicate that pulmonary CCR2(+) T cells and MCP-1 contribute to the pathogenesis of pediatric ILD and might provide a novel target for therapeutic strategies.

Medizinische Fakultät - Digitale Hochschulschriften der LMU - Teil 03/19
Chemokinrezeptorexpression peripherer T-Helferzellen im Zusammenhang mit Klinik und Pathogenese atopischer Erkrankungen bei Kindern

Medizinische Fakultät - Digitale Hochschulschriften der LMU - Teil 03/19

Play Episode Listen Later Nov 25, 2004


Hintergrund und Fragestellung: Die Konfrontation des Immunsystems mit einem definierten Antigen löst eine spezifische Immunantwort aus. Die daran beteiligten TH-Zellen können anhand der von ihnen sezernierten Zytokine in TH1- und TH2-Zellen sowie in weitere Subtypen differenziert werden. Dabei sind TH1-Zellen durch die Synthese von IFN-g charakterisiert, während TH2-Zellen vorwiegend Interleukin-4 produzieren. Die gezielte Auswanderung von TH-Zellen in inflammatorische Gewebe wird unter anderem durch Chemokinrezeptoren, welche chemotaktische Zytokine (sog. Chemokine) binden, gesteuert. TH1-Zellen exprimieren bevorzugt CXCR3 und CCR5, TH2-Zellen dagegen CCR3 und CCR4. TH-Zellen sind an der Pathogenese von Typ I Allergien entscheidend beteiligt. Für die Entwicklung der hinsichtlich der Ausbildung von Typ I Allergien protektiven TH1-Zellen scheint die Auseinandersetzung des Immunsystems mit mikrobiellen Antigenen in der allerfrühesten Kindheit notwendig zu sein. Ziel der vorliegenden Arbeit war es, in einem Pilotprojekt an einem Normalkollektiv zweijähriger Kinder das Expressionsmuster oben genannter Chemokinrezeptoren auf peripheren TH-Zellen zu analysieren. In einem zweiten Schritt sollte untersucht werden, ob ein positiver Zusammenhang zwischen TH2-assoziierten Chemokinrezeptoren und der Familienanamnese hinsichtlich atopischer Erkrankungen, der klinischen Diagnose einer atopischen Dermatitis und anderen in der Allergiediagnostik eingesetzten Parametern besteht, oder sich ein negativer Zusammenhang zwischen den TH1-assoziierten Chemokinrezeptoren und oben genannten Parametern zeigen lässt. Darüber hinaus sollte überprüft werden, ob zwischen der Endotoxinexposition, als Proxy für die mikrobielle Exposition in den ersten Lebensmonaten, und dem Expressionsmuster der Chemokinrezeptoren ein Zusammenhang nachgewiesen werden kann. Ergebnisse:Die Chemokinrezeptoren CCR4, CCR5 sowie CXCR3 waren bei allen Probanden nachweisbar. CCR3 konnte bei acht von 37, IFN-g bei 33 von 42 untersuchten Probanden nachgewiesen werden. IL-4 war nicht nachweisbar. Es bestand ein positiver Trend in der Korrelation zwischen der mRNA-Expression von IFN-g und den Chemokinrezeptoren CCR5 (r=0,571) sowie CXCR3 (r=0,386). Ebenso zeigte sich ein positiver Trend in der Korrelation zwischen CCR5 und CXCR3 (r=0,273). Diese Zusammenhänge waren nicht statistisch signifikant. Dagegen korrelierte die CCR5 mRNA-Expression hochsignifikant (p=0,001) sowie die CCR4 mRNA-Expression grenzwertig signifikant (p=0,046) mit dem Endotoxingehalt in der Muttermatratze der Probanden. Schlussfolgerungen: ·In unstimulierten peripheren T-Helferzellen zweijähriger Kinder ist die Quantifizierung der Chemokinzeptoren CCR4, CCR5 sowie CXCR3 mit Hilfe der real-time RT-PCR möglich. IFN-g ist in der überwiegenden Anzahl der untersuchten Probanden nachweisbar, CCR3 nur bei wenigen, IL-4 bei keinem der Probanden. ·Die mRNA-Expression TH1-/TH2-assoziierter Chemokinrezeptoren in unstimulierten, peripheren T-Helferzellen ist für die Differenzierung von Kindern mit von Kindern ohne atopische Dermatitis nicht hilfreich. ·Dagegen scheint die mRNA-Expression von CCR5 als möglichem Marker einer TH1-Antwort mit dem Symptomenkomplex wheezing zu korrelieren. Dieser Befund muss in Studien mit großen Fallzahlen überprüft werden. Wheezing ist am häufigsten mit viralen Infektionen vergesellschaftet. Die weitere Nachuntersuchung der Kinder im Schulalter wird zeigen, bei welchen Kindern sich dennoch Asthma manifestiert. ·Die perinatale Endotoxin-Exposition ist mit einer erhöhten CCR5 mRNA-Expression peripherer TH-Zellen assoziiert. ·Damit deuten die Befunde auf eine Verwertbarkeit der CCR5 mRNA-Expression als TH1-Marker in unstimulierten peripheren TH-Zellen hin.