Podcasts about CD44

BUFFALO, NY- June 17, 2024 – A new research paper was published on the cover of Aging (listed by MEDLINE/PubMed as "Aging (Albany NY)" and "Aging-US" by Web of Science) Volume 16, Issue 11, entitled, “Mitophagy and cancer: role of BNIP3/BNIP3L as energetic drivers of stemness features, ATP production, proliferation, and cell migration.” Mitophagy is a selective form of autophagy which permits the removal of dysfunctional or excess mitochondria. This occurs as an adaptative response to physiological stressors, such as hypoxia, nutrient deprivation, or DNA damage. Mitophagy is promoted by specific mitochondrial outer membrane receptors, among which are BNIP3 and BNIP3L. The role of mitophagy in cancer is being widely studied, and more specifically in the maintenance of cancer stem cell (CSC) properties, such as self-renewal. Given that CSCs are responsible for treatment failure and metastatic capacity, targeting mitophagy could be an interesting approach for CSC elimination. In this new study, researchers Marta Mauro-Lizcano, Federica Sotgia, and Michael P. Lisanti from the University of Salford describe a new model system to enrich sub-populations of cancer cells with high basal levels of mitophagy, based on the functional transcriptional activity of BNIP3 and BNIP3L. “Briefly, we employed a BNIP3(L)-promoter-eGFP-reporter system to isolate cancer cells with high BNIP3/BNIP3L transcriptional activity by flow cytometry (FACS).” The model was validated by using complementary lysosomal and mitophagy-specific probes, as well as the mitochondrially-targeted red fluorescent protein (RFP), namely mt-Keima. High BNIP3/BNIP3L transcriptional activity was accompanied by increases in i) BNIP3/BNIP3L protein levels, ii) lysosomal mass, and iii) basal mitophagy activity. Furthermore, cancer cells with increased BNIP3/BNIP3L transcriptional activity exhibited CSC features, such as greater mammosphere-forming ability and high CD44 levels. “To further explore the model, we also analysed other stemness characteristics in MCF7 and MDA-MB-231 breast cancer cell lines, directly demonstrating that BNIP3(L)-high cells were more metabolically active, proliferative, migratory, and drug-resistant, with elevated anti-oxidant capacity. Therefore, high levels of basal mitophagy appear to enhance CSC features.” DOI - https://doi.org/10.18632/aging.205939 Corresponding authors - Federica Sotgia - fsotgia@gmail.com, and Michael P. Lisanti - michaelp.lisanti@gmail.com Video short - https://www.youtube.com/watch?v=n872jCkc-q8 Sign up for free Altmetric alerts about this article - https://aging.altmetric.com/details/email_updates?id=10.18632%2Faging.205939 Subscribe for free publication alerts from Aging - https://www.aging-us.com/subscribe-to-toc-alerts 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

On today's episode we'll discuss the findings from a phase 2 study of sorafenib plus intensive chemotherapy in newly diagnosed FLT3-ITD AML, learn more about the inhibition of PLK4 in TP53-mutated AML, and discuss the role of CD44 in Plasmodium falciparum infection.

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.04.19.537468v1?rss=1 Authors: Blondiaux, A., Jia, S., Annamneedi, A., Caliskan, G., Schulze, J., Montenegro-Venegas, C., Wykes, R. C., Fejtova, A., Walker, M., Stork, O., Gundelfinger, E. D., Dityatev, A., Seidenbecher, C. I. Abstract: Epilepsies are multifaceted neurological disorders characterized by abnormal brain activity, e.g. caused by imbalanced synaptic excitation and inhibition. The neural extracellular matrix (ECM) is dynamically modulated by physiological and pathophysiological activity and critically involved in controlling the brain's excitability. We used different epilepsy models, i.e. mice lacking the presynaptic scaffolding protein Bassoon at excitatory, inhibitory or all synapse types as genetic models for rapidly generalizing early-onset epilepsy, and intra-hippocampal kainate injection, a model for acquired temporal lobe epilepsy, to study the relationship between epileptic seizures and ECM composition. Electroencephalogram recordings revealed Bassoon deletion at excitatory or inhibitory synapses having diverse effects on epilepsy-related phenotypes. While constitutive Bsn mutants and GABAergic neuron-specific knockouts(BsnDlx5/6cKO) displayed severe epilepsy with more and stronger seizures than kainate-injected animals, mutants lacking Bassoon solely in excitatory forebrain neurons (BsnEmx1cKO) showed only mild impairments. By semiquantitative immunoblotting and immunohistochemistry we show model-specific patterns of neural ECM remodeling, and we also demonstrate significant upregulation of the ECM receptor CD44 in null and BsnDlx5/6cKO mutants. ECM-associated WFA-binding chondroitin sulfates were strongly augmented in seizure models. Strikingly, Brevican, Neurocan, Aggrecan and link protein Hapln1 levels reliably predicted seizure properties across models, suggesting a link between ECM state and epileptic phenotype. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.03.23.532505v1?rss=1 Authors: Ge, X., Lu, L., Bai, W., Wang, M., Han, C., Du, H., Wang, N., Gao, M., Li, D., Dong, F. Abstract: Exosomes are small vesicles released from cells and present in various mammal biological fluids, such as bovine milk, which worked for skin care for many years besides dairy. In addition, Exosomes were regarded as a vehicle for intercellular communication. Therefore, we aimed to investigate the novel roles of bovine milk-derived exosomes (MK-Exo) on human skin anti-aging. Purified MK-Exo can be directly uptake by the keratinocytes and fibroblast in vitro and upregulate the expression of the natural factors related to skin moisturizing, including Filaggrin (FLG), Aquaporin 3 (AQP3), CD44 in the keratinocytes and hyaluronidase (HAS2) in the fibroblast, and MK-Exo promoted the cell migration of the fibroblast, while rescue its expression of type I collagen (Col I), type III collagen (Col III) after ultraviolet radiation. Furthermore, the phototoxicity test, photoallergy test, repeated skin irritation test, skin allergy test, and patch test confirm the safety of MK-Exo on the skin. Finally, the roles of MK-Exo in preserving moisture and anti-wrinkle were also identified in humans. Then, MK-Exo was smeared on the facial skin of 31 female volunteers twice a day for 28 days, and the functions were evaluated following the safety assessment in vivo. These studies reveal the novel roles of bovine milk-derived exosomes in human skin aging, which opens a new way of skin care. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2022.12.14.520376v1?rss=1 Authors: Zhao, H., Chen, J., Qi, C., Wang, T., Liang, T., Hao, X., Li, X., Yin, X., Yu, T., Zhang, Y. Abstract: Restoring the normal structure and function of injured tendons is one of the biggest challenges faced by the Department of Orthopedics and Sports Medicine. Tendon-derived stem cells (TDSCs), a new type of pluripotent stem cells with multidirectional differentiation potential, are expected to be promising cell seeds for the treatment of tendon injury and tendon-bone healing in the future. In this study, tendon stem cells were successfully isolated from human tissues, which were positive for markers CD44, CD90, and CD105, and exhibited clonality and multilineage differentiation ability. Analysis of single-cell sequencing results and mass spectrometry identification results showed that there were differences in protein expression during CTGF-induced TDSC tendon differentiation. Reverse Co-IP, qPCR, WB, and immunofluorescence detection all confirmed that CTGF directly interacts with KIT, thereby mediating the transcription factor HES1 to regulate the Wnt/{beta}-catenin signaling pathway (GSK3{beta}, {beta}-catenin, TCF4). ChIP-qPCR and dual-luciferase reporter gene assays indicated that HES1 regulates stem cell differentiation by directly regulating the expression of GSK3{beta} in the Wnt/{beta}-catenin pathway. Rats were treated with TDSCs overexpressing the KIT gene after repair surgery. This method had a more ideal recovery effect than other methods through animal behavioral scores, mechanical properties testing, and HE staining tissue observation. This study found that the use of modified human tendon stem cells (hTDSC) could promote graft ligamentization and tendon-bone healing after ACL reconstruction, which could provide an effective way for faster and better recovery from tendon injury. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2022.11.25.517972v1?rss=1 Authors: Maurizi, E., Merra, A., Macaluso, C., Schiroli, D., Pellegrini, G. Abstract: Human corneal endothelial cells are organized in a tight mosaic of hexagonal cells and serve a critical function in maintaining corneal hydration and clear vision. Regeneration of the corneal endothelial tissue is hampered by its poor proliferative capacity, which is partially retrieved in vitro, albeit only for a limited number of passages before the cells undergo mesenchymal transition (EnMT). Although different culture conditions have been proposed in order to delay this process and prolong the number of cell passages, EnMT has still not been fully understood and successfully counteracted. In this perspective, we identified herein a single GSK3 inhibitor, CHIR99021, able to revert and avoid EnMT in primary human corneal endothelial cells (HCEnCs) from old donors until late passages in vitro (P8), as shown from cell morphology analysis (circularity). In accordance, CHIR99021 reduced expression of alpha-SMA, an EnMT marker, while restored endothelial markers such as ZO-1, Na+/K+ ATPase and N-cadherin, without increasing cell proliferation. A further analysis on RNA expression confirmed CHIR99021 induced downregulation of EnMT markers (alpha-SMA and CD44), upregulation of the proliferation repressor p21 and revealed novel insights into the beta-catenin and TGFbeta; pathways intersections in HCEnCs. The use of CHIR99021 sheds light on the mechanisms involved in EnMT and brings a substantial advantage in maintaining primary HCEnCs in culture until late passages, while preserving the correct morphology and phenotype. Altogether, these results bring crucial advancements towards the improvement of the corneal endothelial cells based therapy. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC

Dans ce numéro 16, Lionel Boscher accueille Yann Miro del Valle, président du Comité Départemental de la Loire-Atlantique (44). Chaque comité est composé d'une équipe de bénévoles qui agissent au quotidien pour faire connaître le golf, donner l'envie de débuter et de jouer aux enfants comme aux parents, ou encore organiser des compétitions au sein du département. Le CD44 assure le relai entre la ligue régionale et les 14 clubs du département, tout en ayant un objectif de décliner le projet jeunes et le projet scolaire de la ligue et de la Fédération.  Yann Miro del Valle décrit les moyens dont le CD dispose et présente les différentes actions mises en place, notamment pour ce qui concerne sa mandature entre 2021 et 2024.  Un épisode qui aborde évidemment la mise en place du golf scolaire, ses atouts et ses freins comme le transport. Dans ce numéro, on s'intéresse à ce qui plait aux enfants dans le golf, à l'importance d'un champion, le rôle des parents et à terme comment faire pour les transformer eux aussi en futurs joueurs s'ils ne le sont pas déjà. Un épisode 100% développement de la pratique qui met en lumière les initiatives nombreuses sur ce département et partout en France.Hébergé par Ausha. Visitez ausha.co/politique-de-confidentialite pour plus d'informations.

In this week's episode, we review results of preclinical investigations that sound a note of caution regarding the potential use of JAK inhibitors as treatment for hemophagocytic lymphohistiocytosis (or HLH), research that provides new insights on how CD44 loss of function sensitizes AML cells to the BCL-2 inhibitor venetoclax, and conclude with a report that demonstrates cooperation between B cell receptor signaling and genetic lesions in CDKN2A, CDKN2B and TP53 in Richter transformation.

We've spoken before about the immigrant experience coming from South Asia to the US, but never the other way around! This time, we get to know Jessica Kumar, an American Midwesterner and Co-host of the Invisible India Podcast. Over time, Jessica found herself building a life with her husband and children halfway across the world in India. We sat down to ask Jessica about her work, her transition to life in India, raising bilingual children there, the misconceptions she had before arriving, and much more. Invisible India episode mentioned: Debunking Misconceptions about India @InvisibleIndia on IG @IndiaInvisible on Twitter @TheInvisibleIndia on FB

Hello all! So happy to present 3 poems by Nayanjyoti Baruah! FROM THE POET: I'm Nayanjyoti Baruah, from Assam, India. I'm pursuing M.A. in English Literature from Gauhati University. My poems have been appeared in Tayls, Rasa Literary Review, Felicity, Akhore, Meghali Budhidrom, The Fiction Project, A Too Powerful Word, Necro Magazine etc. I'm the Co-author of The Bag of Knowledge. I've written two essays and four short stories as well. Instagram: https://www.instagram.com/nayanjyoti2544/ Facebook: https://www.facebook.com/nayanjyoti.baruah.3745 Creative Drive is an international podcast produced by J. Alejandro to bring visibility to poets from all walks of life. Now accepting 3 poems or flash fiction! https://cruzfolio.com/you/ Acepto poesia y relatos cortos en español! https://cruzfolio.com/fuerza-creativa/ For more information about the podcast, visit https://cruzfolio.com/creative-drive-podcast/

Oncotarget recently published "CD44+/EPCAM+ cells detect a subpopulation of ALDHhigh cells in human non-small cell lung cancer: A chance for targeting cancer stem cells?" which reported that a comparison between ALDH high cells and CD44 cells have been previously described with no significant correlation. This cross-sectional study analyzed the expression of ALDHhigh/low cells and the positivity for CD44 and epithelium cell adhesion molecule antigens in surgical lung cancer tissues. There was a highly positive correlation between the expressions of ALDHhigh and CD44 /EPCAM cells, with a Pearson’s correlation coefficient equal to 0.69, and Spearman’s correlation coefficient equal to 0.52. The average paired difference between the expression of ALDHhigh and CD44 /EPCAM cells was very close to 0, being 0.1%; there was no difference between these subpopulations in terms of means. The Oncotarget author’s study is the first attempt that identifies a high correlation between the ALDHhigh and the CD44 /EPCAM cells, thus suggesting the possibility to use this superficial marker for future target treatments against lung cancer stem cells. Dr. Beatrice Aramini from The University of Modena and Reggio Emilia said, "The cancer stem cell (CSC) model was proposed over 30 years ago [1] and is a very important field of study in cancer research." As a cancer stem cell marker in a panel of 11 non-small-cell lung cancer tumor samples, 45 NSCLC lines, and 7 small-cell lung cancer lines. In 2013 a panel of lung cancer cell lines from primary tumors and characterized a small subpopulation as strongly positive for CD44, with the main population being weakly positive or negative for CD44. The co-expression of CD90 further narrowed down the putative stem cell population. This showed the putative lung CSC phenotypes of CD166 /CD44 and CD166 /EPCAM with multipotent characteristics of stem cells in lung adenocarcinoma cells. Hence, a triple-positive marker, EPCAM /CD166 /CD44, has recently been described in the human non-small cell lung cancer cell line. Nevertheless, although ALDH is considered an intracellular enzyme and is the most used marker to identify CSCs in lung cancer, the scientific community has never correlated this intracellular marker with an epithelial marker, which may be very useful for targeting lung cancer stem cells. The Aramini Research Team concluded in their Oncotarget Research Paper, “even if we hypothesized that the percentage of CD44 /EPCAM in ALDHhigh cell population would be less than 50% in other patients, the similarity of an intracellular marker highlighting ALDHhigh cell population with a superficial marker CD44 /EPCAM is a very important concept in terms of target treatment. In summary, our research is an important starting point for further studies that are needed to better define the CD44 /EPCAM superficial marker highlighting lung cancer stem cells.” Full text - https://www.oncotarget.com/article/27568/text/

Hintergrund: Hyaluronan (HA) ist ein wichtiger Bestandteil von vielen Geweben und Flüssigkeiten des Körpers. HA beeinflusst die Makro- und Mikroumgebung und kann direkt über Rezeptoren wie CD44 (cluster of differentiation 44) und RHAMM (receptor for HA mediated motility) mit den Zellen wechselwirken. Dadurch hat HA Einfluss auf die Aktivierung, Migration und Proliferation von Zellen sowie auf den Umbau der extrazellulären Matrix. HA kann das Verhalten der Osteoblasten, Osteozyten und Osteoklasten beeinflussen und ist somit ein wichtiger Faktor sowohl für die gesunde Knochenhomöostase als auch für die Frakturheilung. Hyaluronansynthasen (HAS) sind komplexe Membranproteine, die für die Synthese von HA verantwortlich sind. Bei Säugetieren sind drei Isoformen bekannt: HAS1, HAS2 und HAS3. Sie zeigen eine hohe Homologie in ihrer Sequenz und Struktur, unterscheiden sich aber in Stabilität, Syntheserate und Länge des HA. Der genaue Regulierungsmechanismus der HAS ist noch nicht bekannt. Bisher wurde über eine Regulation durch externe Signalmoleküle, Ubiquitinierung oder Phosphorylierung berichtet. In der vorliegenden Arbeit wurde ein Modellsystem zur Untersuchung der Regulation der Aktivität der HAS aufgebaut. Mit diesem sollte die Interaktion der HAS mit dem Aktinzytoskelett als möglicher Regulationsmechanismus untersucht werden. Methoden: Zu diesem Zweck wurden drei Zelllinien hergestellt. Zum einen hTERT immortalisierte hMSCs (human mesenchymal stem cells), die sogenannten SCP1, welche jeweils eine der HAS-Isoformen, fusioniert mit einem eGFP-Tag, stabil exprimieren. Des Weiteren SCP1, die Lifeact-mRFPruby exprimieren, welches F-Aktin fluoreszenzmarkiert. Schließlich doppeltransduzierte hMSCs, welche sowohl HAS-eGFP als auch Lifeact-mRFPruby exprimieren. Als Gentransfersystem wurden Lentiviren eingesetzt. Zuerst wurden die Zellen hinsichtlich der stabilen und funktionellen Expression ihres Transgens anhand verschiedener Methoden untersucht. Mittels Immunfluoreszenzmikroskopie wurde eine Kolokalisation von Aktin und HAS dargestellt. In fluoreszenzmikroskopischen Timelapse-Aufnahmen wurden die Bewegungsmuster der HAS beobachtet. Ergebnisse: Mittels RT-PCR, Western Blot und Fluoreszenzmikroskopie wurde nachgewiesen, dass die Zelllinien SCP1-HAS1-eGFP D6, SCP1-HAS2-eGFP und SCP1-HAS3-eGFP E6 alle ihr jeweiliges HAS-eGFP-Gen stabil exprimieren. Die Funktionalität der HAS-eGFP wurde mit einem HA-spezifischen ELISA und mit einem selbst etablierten Aktivitätsassay untersucht, welcher das HA durch den biotinylierten HA-Bindekomplex (bHABC) färbt. Im ELISA zeigten alle Zelllinien eine statistisch signifikant höhere Hyaluronanproduktion als die Negativkontrolle. Die HAS3-überexprimierende Zelllinie erzielte von allen die höchste HA-Konzentration. In der Färbung mit bHABC war deutlich zu erkennen, dass diejenigen Zelllinien, in denen eine der HAS-eGFP-Isoformen überexprimiert wurde, eine stärkere Braunfärbung zeigten als Zellen der Negativkontrolle. Für den Nachweis, dass die HAS-eGFP in der Membran lokalisiert sind, wurden Immunfluoreszenzfärbungen gegen den Oberflächenmarker CD44 durchgeführt. Die fluoreszenzmikroskopischen Aufnahmen zeigten an Stellen, die durch die CD44-Färbung eindeutig als Membran zu erkennen sind, ebenfalls ein Signal für die HAS-eGFP. Dies bedeutet, dass die drei Isoformen der HAS-eGFP dort in der Zellmembran integriert vorlagen. Um eine Kolokalisation der HAS-eGFP mit dem Aktinzytoskelett darstellen zu können, erfolgte außerdem eine Färbung des Aktins mit Phalloidin. Bei allen Zelllinien konnte an ausgewählten Stellen eine solche Kolokalisation gesehen werden. Die hMSC-Lifeact-mRFPruby-Zellen wurden lebendig und fixiert im Fluoreszenzmikroskop betrachtet. Sie lieferten eine gute Darstellung des Zytoskeletts mit Stressfasern im Zellkörper und Aktinfilamenten im Zellcortex. Auffallend war, dass in den lebenden Zellen kurze Aktinfilamente zu sehen waren, die sich bei den fixierten Zellen nicht beobachten ließen. Um eine Interaktion zwischen den HAS-eGFP und dem Aktinzytoskelett in lebenden Zellen untersuchen zu können, wurden von den doppeltransduzierten hMSCs Timelapse-Aufnahmen angefertigt. Darin stellten sich die grün fluoreszierenden HAS-eGFP als globuläre Strukturen dar, die entlang der Aktinfilamente angeordnet waren und sich auch entlang dieser bewegten. Schlussfolgerung: Mit diesen Zellen wurde ein Modellsystem geschaffen, mit welchem eine Regulation der HAS über die Interaktion mit dem Zytoskelett untersucht werden kann. Genaueres Wissen über diesen Mechanismus kann für zukünftige Therapieansätze bei Frakturen und bei Knochenerkrankungen, wie z.B. der Osteoporose, richtungsweisend werden.

Vincent, Dickson, and Daniel discuss identification of an erythrocyte protein essential for invasion of Plasmodium falciparum, and introduce a new case study. Hosts: Vincent Racaniello, Dickson Despommier, and Daniel Griffin Links for this episode: Dermatobia hominis (Wikipedia) Plasmodium falciparum erythrocyte invasion (Science) Plasmodium life cycle (TWiP #10) Letters read on TWiP 90 Contact Send your questions and comments (email or mp3 file) to twip@twiv.tv Subscribe Subscribe to TWiP (free) in iTunes, by the RSS feed or by email

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.

Thu, 13 Mar 2014 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/16770/ https://edoc.ub.uni-muenchen.de/16770/1/Waeschle_Johanna.pdf Waeschle, Johanna

Background: CD44 splice variants are long-known as being associated with cell transformation. Recently, the standard form of CD44 (CD44s) was shown to be part of the signature of cancer stem cells (CSCs) in colon, breast, and in head and neck squamous cell carcinomas (HNSCC). This is somewhat in contradiction to previous reports on the expression of CD44s in HNSCC. The aim of the present study was to clarify the actual pattern of CD44 expression in head and neck epithelia. Methods: Expression of CD44s and CD44v6 was analysed by immunohistochemistry with specific antibodies in primary head and neck tissues. Scoring of all specimens followed a two-parameters system, which implemented percentages of positive cells and staining intensities from − to +++ (score = %×intensity; resulting max. score 300). In addition, cell surface expression of CD44s and CD44v6 was assessed in lymphocytes and HNSCC. Results: In normal epithelia CD44s and CD44v6 were expressed in 60–95% and 50–80% of cells and yielded mean scores with a standard error of a mean (SEM) of 249.5±14.5 and 198±11.13, respectively. In oral leukoplakia and in moderately differentiated carcinomas CD44s and CD44v6 levels were slightly increased (278.9±7.16 and 242±11.7; 291.8±5.88 and 287.3±6.88). Carcinomas in situ displayed unchanged levels of both proteins whereas poorly differentiated carcinomas consistently expressed diminished CD44s and CD44v6 levels. Lymphocytes and HNSCC lines strongly expressed CD44s but not CD44v6. Conclusion: CD44s and CD44v6 expression does not distinguish normal from benign or malignant epithelia of the head and neck. CD44s and CD44v6 were abundantly present in the great majority of cells in head and neck tissues, including carcinomas. Hence, the value of CD44s as a marker for the definition of a small subset of cells (i.e. less than 10%) representing head and neck cancer stem cells may need revision.

Zielsetzung und Fragestellung: Humane mesenchymale Stammzellen (hMSC) exprimieren eine Vielzahl verschiede-ner Antigene. Dennoch ist es nicht möglich eine eindeutige Phänotypisierung dieses Zelltyps vorzunehmen, da keiner der bekannten Zellmarker spezifisch ist. Daher war es Ziel dieser Studie, durch die Etablierung einer 7-Farben Fluoreszenz hMSC auf Einzelzellebene durch ein geeignetes Markerprofil zu charakterisieren und sie ge-genüber Osteoblasten und Fibroblasten abgrenzen zu können. Material und Methoden: Kommerziell erhältliche HMSC, humane Osteoblasten und Fibroblasten wurden als adhärente Zellen auf Einzelzellniveau einer simultanen Mehrfach-Immunfluoreszenzfärbung gegen die Antigene CD105, CD106, CD44, Kollagen IV, Fibronektin und F-Aktin unterzogen. Anschließend wurde mittels eines Sagnac Inter-ferometers eine spectrale Bildanalyse mit Dekomposition der einzelnen Farbstoffe durchgeführt. Ergebnisse: Hinsichtlich aller untersuchten Zellmarker zeigten hMSC ein positives Färbeergebnis, während in humanen Osteoblasten und Fibroblasten CD105 und CD106 nicht nach-gewiesen werden konnte. Eine Unterscheidung zwischen letzteren Zelltypen konnte durch CD44 gewährleistet werden, welches nur in Osteoblasten ein positives Ergeb-nis zeigte. Alle verwendeten Farbstoffe konnten eindeutig in der Spectralanalyse bis zu einem Wellenlängenabstand von 10nm voneinander getrennt werden. Schlussfolgerungen: Es ist in dieser Studie gelungen, ein geeignetes Markerprofil zu definieren, um hMSC von anderen Zellen des Binde- und Stützgewebes abzugrenzen. Besonders die Spectralanalyse eines simultan angewandten Phänotypisierungsprofils auf Einzel-zellniveau erscheint bei der großen Heterogenität dieser Stammzellen als potentes Werkzeug zur Untersuchung gegenüber anderen Zelllinien. Besonders die Oberflä-chenproteine CD105, CD106 und CD44 erscheinen als äußerst geeignete Kandida-ten zur Charakterisierung von hMSC.

A better understanding of the initial mechanisms that lead to arthritic disease could facilitate development of improved therapeutic strategies. We characterized the synovial microcirculation of knee joints in susceptible mouse strains undergoing intradermal immunization with bovine collagen II in complete Freund's adjuvant to induce arthritis (i.e. collagen-induced arthritis [ CIA]). Susceptible DBA1/J and collagen II T-cell receptor transgenic mice were compared with CIA-resistant FVB/NJ mice. Before onset of clinical symptoms of arthritis, in vivo fluorescence microscopy of knee joints revealed marked leucocyte activation and interaction with the endothelial lining of synovial microvessels. This initial inflammatory cell response correlated with the gene expression profile at this disease stage. The majority of the 655 differentially expressed genes belonged to classes of genes that are involved in cell movement and structure, cell cycle and signal transduction, as well as transcription, protein synthesis and metabolism. However, 24 adhesion molecules and chemokine/cytokine genes were identified, some of which are known to contribute to arthritis ( e. g. CD44 and neutrophil cytosolic factor 1) and some of which are novel in this respect ( e. g. CC chemokine ligand-27 and IL-13 receptor alpha(1)). Online in vivo data on synovial tissue microcirculation, together with gene expression profiling, emphasize the potential role played by early inflammatory events in the development of arthritis.

We present here the first evidence linking CD44 signaling to c-Jun expression and cell cycle progression in myeloid cell line models. CD44 ligation with the anti-CD44 monoclonal antibodies have been shown to induce differentiation and inhibit the proliferation of human acute myeloid leukemia (AML) cells, and c-Jun is involved in the regulation of these processes. The effects of anti-CD44 monoclonal antibody A3D8, on myeloid cells were associated with specific disruption of cell cycle events and induction of G0/G1 arrest. Induction of G0/G1 arrest was accompanied by an increase in the expression of p21, attenuation of pRb phosphorylation and associated with decreased CDK2 and CDK4 kinase activities. We observed that A3D8 treatment of AML patient blasts and HL60/U937 cells led to the downregulation of c-Jun expression at mRNA and protein level. Transient transfection studies showed the inhibition of c-jun promoter activity by A3D8, involving both AP-1 sites. Furthermore, A3D8 treatment caused a decrease in JNK protein expression and a decrease in the level of phosphorylated c-Jun. Ectopic overexpression of c-Jun in HL60 cells was able to induce proliferation and prevent the anti-proliferative effects of A3D8. Targeting of G1 regulatory proteins and the resulting induction of G1 arrest by A3D8 may provide new insights into anti-proliferative and differentiation therapy of AML.

Two human stromal cell lines were established previously from bone marrow-derived primary long-term cultures by immortalization using the SV40 large T antigen and cellular cloning. After irradiation, the fibroblast-like cell lines L87/4 and L88/5 support hematopoietic differentiation of allogeneic cord blood cells in vitro. The stromal cells do not express CD34 and CD50, but some adhesion molecules and integrins, such as CD44, CD54 and CD58. Their expression profiles on RNA and protein levels are suggestive of their osteogenic potency. The quality and quantity of osteocalcin and osteopontin protein expression depended on the culture conditions. Expression of the osteogenic markers increased over time in culture, especially in cells growing in clusters. The stromal cells also expressed collagens I and V, but did not show any expression of collagens II and III. The potentially osteoblastic stromal cells were transplanted into NOD/SCID recipient mice by intravenous injection and were found in various mesenchymal organs up to 10 weeks after transplantation. Osteocalcin-positive human stromal cells could be detected in the bone marrow, thymus, liver, brain and gut of the recipient animals. In summary, there is evidence that human bone-marrow-derived stromal cells have to be considered mesenchymal progenitors, persistently expressing osteogenic markers in vitro and in vivo. Copyright (C) 2001 S, Karger AG, Basel.

Fri, 1 Jan 1993 12:00:00 +0100 https://epub.ub.uni-muenchen.de/8879/1/8879.pdf Scriba, Peter Christian; Boergen, K. P.; Bahn, R. S.; Heufelder, A. E.