Tumor associated antigens (TAAs)

Top PDF Tumor associated antigens (TAAs):

mRNA expression of tumor associated antigens in patients with chronic lymphocytic leukemia

mRNA expression of tumor associated antigens in patients with chronic lymphocytic leukemia

There are several types of tumor associated antigens (TAAs) (Table 3): Cancer/germline antigens of the BAGE or the MAGE gene families (Boel et al. 1995, Liu et al. 2004). These antigens are considered to be good candidate antigens to future immunotherapies because of their expression on tumor cells and on normal germ cells but not in other normal somatic tissues. Other types of TAAs are expressed in normal tissues but overexpressed in tumor cells, e.g. HER2/neu. The use of these TAAs as targets is not unproblematic because of the possible danger of eliciting autoimmune reactions (Stockinger 1999). There are suggestions that a two log difference in the expression of TAAs on normal cells versus tumor cells is required for safe immunotherapy. Mutated proteins constitute further target structures for immunotherapies. For example the bcr-abl mutation, characteristically observed in chronic myeloid leukemia, results from the t(9;22) translocation, the so called the “Philadelphia chromosome”. This gene rearrangement results in the production of a novel oncoprotein, BCR/ABL, a constitutively active tyrosine kinase (Bocchia et al. 2005).
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Gutenberg Open Science: Tolerance and immunity to human tumor-associated antigens

Gutenberg Open Science: Tolerance and immunity to human tumor-associated antigens

To study whether or not the A2.1-restricted Hu T cell repertoire is affected by Tyr- specific self tolerance too, Hu CD8 + T lymphocytes underwent primary in vitro induction with mature A2 + autologous DC pulsed with either mTyr or hTyr peptides and were tested for specific lytic activity after 3 to 4 rounds of DC/Ag-based restimulation. Allo A2.1-reactive and FluM1 (58-66)-specific Tg mouse CTL served as positive and negative control, respectively (data not shown). While Ag-specific CD8 + effector CTL could be raised in 3 out of 3 donors, as shown for donor 1 in Fig. 5A, hTyr- as compared to mTyr-stimulated CTL required about 5-fold more peptide to mediate equivalent lysis of T2 targets loaded with the primary Ag (Fig. 5B, C). However, there was no advantage to the use of the more efficient mTyr CTL in crossrecognizing the hTyr peptide (Fig. 5B). Consistent with this finding, A2.1 + SY targets infected with MVA-mTyr, as opposed to SY MVA-hTyr, were killed by mTyr CTL only (Fig. 5D, F). Regardless of the higher versus intermediate avidity of mTyr and hTyr CTL, respectively, both CTL were sufficiently effective to lyse A2.1 + Hu melanoma targets that express hTyr protein at high level, such as Malme 3M and NA8- Mel-Tyr transfectants (Fig. 5D, E, F, G). Both, lack of NK-activity and exclusive A2.1/Ag complex-specificity by Tyr-specific CTL was demonstrated by their ignorance of K562, NA8-Mel controls (Fig. 5D, E, F, G), and Tyr + A2.1 - SK28 tumor targets (data not shown). These studies demonstrate for the first time that the hTyr- specific T cell repertoire in man is also governed by partial self tolerance that allows a window of opportunity for residual higher avidity self Tyr-specific T cells to escape tolerance induction. Although mTyr-reactive CTL of increased efficiency could be raised from Hu T lymphocytes, the employment of the xenogeneic mTyr peptide homologue did not rescue hTyr-specific partial tolerance.
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Genetically modified natural killer cells specifically recognizing the tumor-associated antigens ErbB2/HER2 and EpCAM

Genetically modified natural killer cells specifically recognizing the tumor-associated antigens ErbB2/HER2 and EpCAM

These results demonstrate that efficient retargeting of NK- 92 cytotoxicity can be achieved, and might allow the gen- eration of potent cell-based therapeutics for the treatment of ErbB2 and Ep-CAM expressing malignancies. This ther- apeutic approach might be applicable for a large variety of different cancers where suitable cell surface antigens have been identified.

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Gutenberg Open Science: Identification of preferentially targeted tumor-associated antigens in melanoma patients via mRNA stimulation of CD8+ 
blood lymphocytes

Gutenberg Open Science: Identification of preferentially targeted tumor-associated antigens in melanoma patients via mRNA stimulation of CD8+ blood lymphocytes

We assume that in cases of advanced melanoma, spontaneous responses against antigens expressed by the tumor do exist at levels differing among antigens and among patients, but lead to T cell frequencies still below the detection limits available with current detection methods. The very low frequencies mentioned above could only be determined using labor intensive methods based on mixed lymphocyte-peptide microcultures performed by stimulating tetramer-positive cells under limiting dilution conditions. Such an approach involves long term stimulation of lymphocytes and analysis of a high number of CTL clones. Frequencies that can still be detected among ex vivo CD8+ T cells using tetramer or ELISPOT technology are rather in the order of 10 -4 (Letsch, 2000; Lonchay, 2004). In other cases where the disease might not have yet spread from the initial tumor and invaded peripheral lymph nodes, the first round of amplification of rare naŽve antigen-specific T cells by the tumor might not have yet occurred. The results obtained with Melan-A in normal donors indicate that these naŽve cells can be in principle amplified under the stimulation conditions, as reactivities toward Melan-A/MART-1 could be stimulated in normal donors which have been shown to bear exclusively Melan-A precursors with a naŽve CCR7 + CD45RA hi phenotype (Pittet, 1999; Romero, 2002). Nevertheless, this definition of the naŽve phenotype has been recently challenged, as some memory cells have been shown to re-express CCR7 (Schwendemann, 2005) or CD45RA (Carrasco, 2006). On the other hand, we assume that apart the case of Melan-A/MART-1, the starting frequencies of other antigen-specific naŽve precursors might be too low (probably below 10 -7 ) to be expanded to such an extent that they can be detected after two stimulations. Otherwise, we would have probably found reactivities against other tumor antigens in the four normal persons we analyzed (Figure 3.25). In all the cases, it appears necessary to submit those precursors to in vitro stimulation to either prime naŽve cells that have not yet be activated by the tumor and further expand them or/and to expand those experienced responders to frequencies that become detectable with available methods. Beside this requirement to increase starting T cell frequencies, in vitro stimulation has also an additional role. Resting memory and naŽve CD8+ T cells, when tested ex vivo, would not be able to secret detectable amounts of IFN-€ during the 20h of antigen contact applied in the ELISPOT assay. In vitro stimulation enables them to acquire or re-acquire effector functions which can be further detected in the assay five days later.
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Screening of human tumor antigens for CD4 T cell epitopes by combination of HLA-transgenic mice, recombinant adenovirus and antigen peptide libraries

Screening of human tumor antigens for CD4 T cell epitopes by combination of HLA-transgenic mice, recombinant adenovirus and antigen peptide libraries

Thus, tumor antigen-specific CD4 + T cells essentially contribute to anti-tumor immunity which has strongly stimulated the interest in the identification of their target epitopes. The widely applied ‘‘reverse immunology’’ approach for epitope identification is based on in silico prediction of antigen-derived peptides with high binding affinities to a specific MHC molecule. The candidate sequences are then synthesized and loaded onto DC for in vitro priming of autologous CD4 + T cells. Finally, peptide-reactive T cells are employed to demonstrate generation and presentation of the corresponding epitope by antigen-loaded target cells. Unfortu- nately, most allele-specific peptide binding motifs of MHC class II molecules are highly degenerated making the algorithm-based in silico prediction of potential CD4 + T cell epitope sequences still speculative. Thus, after extensive T cell culture only a subgroup of predicted peptides can be verified as natural epitopes. Though different CD4 + T cell epitopes from tumor antigens such as CEA [22], p53 [23] or TRP-2 [24] have been defined by in silico prediction, we set out to overcome the drawbacks of this strategy by setting up a comprehensive screening approach based on the immunization of HLA-transgenic mice with recombinant adeno- virus encoding human melanoma antigens and subsequent scanning of the T cell responses in vitro with the help of combinatorial antigen-specific peptide libraries. This approach allowed us to directly concentrate our efforts on naturally processed tumor antigen-specific epitopes presented by a given MHC class II restriction element. As target antigens the melanoma differentiation antigens TRP-1 and TRP-2 were chosen, since both proteins are known to be frequently recognized by CD8 + T cell in melanoma patients [25,26]. In fact, targeting of TRP-1 by adoptively transferred CD4 + T cells was recently shown to mediate eradication of large established tumors in mice [14].
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Cancer-associated fibroblasts stimulate primary tumor growth and metastatic spread in an orthotopic prostate cancer xenograft model

Cancer-associated fibroblasts stimulate primary tumor growth and metastatic spread in an orthotopic prostate cancer xenograft model

Prostate cancer (PCa) is the most frequently diagnosed malignant tumor and the second-leading cause of cancer- related death in men in developed countries 1 – 3 . Patients diagnosed at an early, organ-confined stage can mostly be cured by radical prostatectomy or radiotherapy. However, many patients still present with or progress to metastatic disease 4 , 5 , and palliative androgen deprivation therapy (ADT) in combination with the chemothera- peutic agent docetaxel or the androgen-receptor-signaling inhibitors abiraterone or apalutamide is the standard treatment for this condition 6 – 10 . Virtually all patients acquire resistance to ADT after one to ten years progressing to castration-resistant prostate cancer (CRPC), for which several life-prolonging palliative treatment options are available 11 . In addition to its reliance on androgen receptor signaling from organ-confined to metastatic, castration-resistant disease 12 , 13 , other hallmarks of PCa are its multifocality 14 , its multiclonality 15 , 16 and its notable inter- and intraindividual heterogeneity 17 – 20 ; due to these qualities, PCa management is a major challenge, and thus, further elucidation of the unique biology of this disease is urgently needed. The unique microenvironment (known as the “tumor microenvironment” or “TME”) of the prostate concerning its cellular constitution and the concentration of cytokines, growth factors and hormones is an important factor in PCa development and open
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Seizures associated with antibodies against cell surface antigens are acute symptomatic and not indicative of epilepsy: insights from long-term data

Seizures associated with antibodies against cell surface antigens are acute symptomatic and not indicative of epilepsy: insights from long-term data

Results Patients had surface antibodies against the N-methyl- d -aspartate receptor (NMDAR, n = 6), leucine-rich glioma inactivated protein 1 (LGI1, n = 11), contactin-associated protein-2 (CASPR2, n = 8), or antibodies against the intracellular antigens glutamic acid decarboxylase 65 kDa (GAD65, n = 13) or Ma2 (n = 1). Patients with surface antibodies reached first seizure-freedom (88% vs. 7%, P < 0.001) and terminal seizure-freedom (80% vs. 7%, P < 0.001) more frequently. The time to first and terminal seizure-freedom and the time to freedom from ASM were shorter in the surface antibody group (Kaplan–Meier curves: P < 0.0001 for first seizure-freedom; P < 0.0001 for terminal seizure-freedom; P = 0.0042 for terminal ASM-freedom). Maximum ASM defined daily doses were higher in the groups with intracellular antibodies. Seizure-freedom was achieved after additional immunotherapy, not always accompanied by increased ASM doses. Titers of surface antibodies but not intracellular antibodies decreased over time.
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OPUS Würzburg | Identifizierung und Charakterisierung des BARB-4 Antigens

OPUS Würzburg | Identifizierung und Charakterisierung des BARB-4 Antigens

[191]. Als Metastasierung bezeichnet man den Vorgang bei dem sich einzelne Krebszellen aus dem Tumor ablösen und über das Blut oder die Lymphe in andere Körperareale wandern, in denen sie sich neu ansiedeln und vermehren. Die Fähigkeit eines Tumors Metastasen auszubilden verschlechtert die Heilungschancen der betroffenen Patienten meist drastisch. Das Potential zur Metastasierung hängt dabei von mehreren Faktoren, wie beispielsweise seiner Umgebung oder der Angiogenese ab. Hauptsächlich ist jedoch der molekulare Phänotyp des Tumors ausschlaggebend. Einzelne Zellen des Primärtumors können sich genetisch verändern und so wichtige Eigenschaften wie beispielsweise invasives Wachstum erlangen, welche für eine Metastasierung essentiell sind. Diese Veränderung ist jedoch nicht nur funktionell, sondern wirkt sich auch auf den Phänotyp der entsprechenden Tumorzelle aus. In zahlreichen Analysen konnte bestätigt werden, dass phänotypische Unterschiede zwischen primären und sekundären Tumorzellen bestehen. So existieren beispielsweise unterschiedliche Expressionslevel von Adhäsionsproteinen wie CD44, CD54 und CD146 zwischen metastasierenden und nicht-metastasierenden Tumorzellen [303-306]. Für die nachfolgende Betrachtung spielen sowohl das äußere Erscheinungsbild (Phänotyp) der metastasierenden Zelle als auch ihre funktionellen Aspekte eine wichtige Rolle. Bei dem Antikörper BARB-4 konnte eine hemmende Wirkung auf die Tumorzellmotilität und Tumorzelladhäsion festgestellt werden. Wie oben beschrieben, sind dies wichtige Vorgänge bei der Entstehung von Metastasen. Die Beweglichkeit bzw. das Ausbreitungsvermögen von metastasierenden Zellen ist essentiell für die Migration in den Blutstrom und die Invasion der Tumorzelle in neue Gewebeareale. Die Adhäsion unterstützt die Anhaftung der intravaskulär lokalisierten Tumorzellen im Blut an das Endothelium der Blutgefäße [191]. In dieser Arbeit konnte gezeigt werden, dass der natürliche, monoklonale Antikörper BARB-4 eine tumorspezifische TAF15 Variante als Target erkennt. TAF15 scheint dabei ebenso wie BARB-4 in beide Prozesse involviert zu sein.
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Improved Drug Delivery of next-generation Antibody-Drug Conjugates by utilizing tumor-associated proteases

Improved Drug Delivery of next-generation Antibody-Drug Conjugates by utilizing tumor-associated proteases

Die zielgerichtete Therapie mit tumor-spezifischen Antikörpern hat sich im Laufe der Zeit in der klinischen Onkologie etabliert, was durch die Vielzahl an zugelassenen Medikamenten belegt ist. Dennoch gibt es Limitationen bei Antikörpern, die Zelloberflächenantigene adressieren. Onkologische Therapeutika müssen im Rahmen der Tumortherapie in der Lage sein, alle Krebszellen zu erreichen. Wenn unbehandelte Regionen nicht therapiert werden, können diese zu einem Tumor-Rezidiv führen. Die verringerte Tumorpenetration und Wirkstoffabgabe von herkömmlichen Antikörper-basierten Medikamenten stellen eine große Herausforderung für die effektive Behandlung von soliden Tumoren dar. Im Rahmen von Antikörper-Wirkstoff Konjugaten (ADCs), fokussierten sich die größten Forschungsaktivitäten auf neuartige Linker Strukturen, Optimierungen von zytotoxischen Arzneistoffen und Technologien für Positions-spezifische Konjugationen. Weniger Beachtung erhielt die Modifikation des Antikörpergrundgerüsts oder Antikörperalternativen für die Optimierung des Arzneistofftransports. In diesem Kontext spielt die Molekülgröße des ADC Transportvehikels eine essenzielle Rolle für den Transport des zytotoxischen Wirkstoffs zu den Tumorzellen.
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Immunochemische Charakterisierung des p83/100-Antigens von Borrelia burgdorferi

Immunochemische Charakterisierung des p83/100-Antigens von Borrelia burgdorferi

Der monoklonale Antikörper 2G3 wurde für elektronenmikroskopische Untersuchungen verwendet. Die subzelluläre Lage des p83/100-Antigens konnte durch diesen hochaffinen Antikörper und Antikörper-gekoppelte Goldpartikel sichtbar gemacht werden. Die Abb. 3.15 veranschaulicht, daß es in den Randstrukturen des Protoplasmazylinders liegt. Die Goldpartikel sind allerdings nur in den Abschnitten zu sehen, in denen die Integrität der Zylinderwand zerstört ist und die inneren Schichten zugänglich sind. Demzufolge liegt das Epitop von 2G3 wohl auf der Innenseite der Zylinderwand oder an der darunter liegenden Protoplasmamembran. Anteile des p83/100-Antigens sind somit auf der Innenseite des Protoplasmazylinders vorhanden. Luft et al. hatten schon 1992 mittels eines goldmarkierten Antikörpers elektronenmikroskopische Aufnahmen vom p83/100-Antigen erhalten. Ihnen war es nicht möglich zu bestimmen, ob es auf der Oberfläche des Protoplasmazylinders lokalisiert ist; angesichts der Lage und voraussichtlichen helikalen Struktur mutmaßten sie, das Protein könnte Bestandteil einer helikalen Fibrille auf der Oberfläche des Protoplasmazylinders sein (50). Bereits 1991 konnten Volkmann und Mitarbeiter eine Assoziation des p83/100-Antigens zum Flagellin nachweisen, indem sie nach Aufreinigungsschritten durch Separation und Solubilisierung von Borrelien- präparationen diese beiden Proteine in den selben Fraktionen wiederfanden (85). Hinzu kommt, daß Eiffert et al. 1992 berichteten, sie hätten ein rekombinantes Protein (p200) hergestellt, dessen korrespondierendes Nativprotein ein Molekulargewicht von 97 kD hätte. Dieses wurde mittels monoklonaler Antikörper eindeutig als im periplasmatischen Raum liegend und flagellenassoziert identifiziert (27). Ob dieses Protein mit dem p83/100- Antigen identisch ist, ist jedoch nicht erwiesen.
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Untersuchungen zur Signaltransduktion des tumorassoziierten Antigens EpCAM

Untersuchungen zur Signaltransduktion des tumorassoziierten Antigens EpCAM

Tumorzellen besitzen nicht nur einen entarteten Zellzyklus, welcher dazu führt, dass ein Primär- tumor entsteht, sondern es kommt auch zu einem Abwandern aus dem Tumorzellverbund, wel- cher von der umgebenden extrazellulären Matrix zusammengehalten wird. Normale epitheliale Zellen können sich nicht aus diesem „Kollektiv“ lösen, abwandern, in der Blutzirkulation überle- ben und an anderen Orten lokalisieren und wieder beginnen zu wachsen (Liotta, 2004; Joyce and Pollard, 2009). Dies wird in Tumorzellen, neben den bereits erwähnten Mechanismen, durch Regulierung von Zell-Adhäsionsmolekülen sowie durch eine Umschichtung und/oder einen Abbau der extrazellulären Matrix bewirkt. Nachdem sich eine Tumorzelle aus dem Pri- märtumor gelöst hat, wandert sie durch Abbau der extrazellulären Matrix (EZM) durch das sie umgebende Stroma, bis sie auf ein Lymph- oder Blutgefäß trifft, welches sie durchwandern kann. Durch diesen Eintritt in ein zirkulierendes System kann die Zelle nun an entlegene Stellen im Körper wandern. Die Tumorzellen bleiben sodann an Endothelien oder subendothelialen Basalmembranen haften und dringen dort in das umgebende Stroma ein. Tumorzellen können dort erst einmal ruhen oder kleine Metastasen (Mikrometastasen) bilden, welche meist der pri- mären Diagnostik entgehen. Jahre später können diese Zellen das Wachstum wieder aufneh- men und makroskopische, ertastbare Metastasen bilden (Mareel et al., 2009).
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Identification of target antigens in AML

Identification of target antigens in AML

(SCT). Currently, cancer patients commonly receive a combination of treatments, including surgery (especially for solid tumors such as breast cancer, lung cancer and prostate cancer), radiation therapy, chemotherapy, immunotherapy and SCT (especially for hematological cancers). Immunotherapy utilizes the host immune responses to produce potent cancer destruction; whereas, targeted therapies commonly aim to block essential molecular pathways crucial for proliferation and maintenance of cancer. But NCI claims that immunotherapy is one type of targeted therapies, which possibly indicates that there is obscure boundary between immunotherapy and targeted therapy. Since they both are focusing on suitable “targets” on tumor cells, immunotherapy and targeted therapy play very important roles in the development of new/novel anticancer drug.
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Identification of minor histocompatibility antigens

Identification of minor histocompatibility antigens

It has been shown that CD4 + T cells play an important role in GvHD (van Els et al., 1989; van Els et al., 1990; Shenoy et al., 1998) and GvL responses (Faber et al., 1995; Alyea et al., 1998; Alyea et al., 2001) after allogeneic BMT. Thus, for separating GvL from GvHD responses, it is important to know the antigens recognized by CD4 + T cells. However, current methods for the identification of antigens presented on MHC class II are complicated and time-consuming procedures. It is known that B cells require T cell help for switching their isotype and the production of highly specific antibodies. Therefore, two approaches for the identification of mHA presented on MHC class II should be taken in parallel (Fig.3). First, mHA-specific CD4 + T cell clones involved in the cellular immune response after BMT should be isolated. Second, the targets of antibody response after BMT should be identified with the SEREX method. Polymorphisms should be identified by comparing the sequences of the genes encoding the antigens in patient and donor (before and after BMT). Polymorphic antigens would be candidate mHAs. These antigens should then be tested in a recognition assay with mHA-specific T cell clones isolated from the patient after BMT. This strategy should give an answer to the question, whether the humoral and cellular immune responses are directed against the same or different antigens. The specific recognition of these candidate mHAs by the CD4 + mHA-specific T cell clones would provide evidence that these antigens truly represent mHAs, and that the serological approach can be used to identify MHC class II-restricted antigens recognized by CD4 + T cell clones.The role of these antigens in the immune response after BMT should additionally be examined by measuring the frequency of the T cells specific for these antigens before and after BMT.
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Chemokine im Tumor-Mikromilieu

Chemokine im Tumor-Mikromilieu

Die Rolle, die Chemokine in der Angiogenese spielen, eröffnet die Möglichkeit von neuen Anwendungen in der Krebstherapie. Es könnte lohnend sein, eine therapeutische Anwendung für angiostatische Chemokine wie CXCL4, CXCL9, CXCL10 und CXCL11 zu finden. Diese Chemokine könnten entweder durch direkte Applikation oder über gentherapeutische Ansätze in einen Tumor eingebracht werden, um die Balance des Mi- kromilieus von einem angiogenen Zustand in einen angiostatischen zu verschieben und damit das Tumorwachstum zu unterbinden. Ein bekanntes Beispiel einer Tumorthera- pie, die einen inhibierenden Wirkstoff einsetzt, ist der Einsatz von Interferon-α (INFα). 76 Vgl. Yao et al. (2005).
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Lysine acetylation of major Chlamydia trachomatis antigens

Lysine acetylation of major Chlamydia trachomatis antigens

Western blot of CtB proteome probed with speci fic anti- acetylated lysine antibody showed over a dozen of speci fic lysine acetylated protein bands including also those with molecular masses corresponding to the above mentioned 5 major CtB antigens ( Fig. 2 and Supplementary data Fig. E10), with the two most intense bands at 17 and 30 kDa belonging possibly to various ribosomal proteins and urydilate kinase enzyme, as inferred from the immunoproteomics results from our parallel study (unpub- lished). Immunoblotting studies showed that CtB proteins contain acetylated lysines when grown in McCoy cells ( Fig. 2 and Supplementary data Fig. E10) and also demonstrated speci ficity, since there are no corresponding bands in conjugate controls as analyzed by Image Quant TL software. Sixteen acetylated proteins were detected ( Fig. 2 . and Supplementary data Fig. E10) that ranged in size from 14 kDa to 130 kDa. This finding besides its con firmatory role for the big part of selected AcK protein candidates, also demonstrates that there are far more acetylated CtB proteins than our initial selection. Regarding the PmpB and PmpE that were not recognized as trachoma relevant antigens in our immunoproteomic study (unpublished) we could not observe their full length protein bands as acetylated and there is a possibility that they are present as fragments as there are faint bands at approximately 130 and 80 kDa [8] .
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Hypermethylation of CDKN2A exon 2 in tumor, tumor-adjacent and tumor-distant tissues from breast cancer patients

Hypermethylation of CDKN2A exon 2 in tumor, tumor-adjacent and tumor-distant tissues from breast cancer patients

clinicopathological parameters. Weak but significant negative correlations were found between the methyla- tion status in both, tumors and tumor-distant tissues, and the proliferative activity of the tumor. In addition, all tumors of the luminal A and luminal B subtype were found to show substantially higher methylation levels than the breast tissues from healthy women, whereas in two patients the tumors of which belonged to the triple negative and the HER2/neu positive subtype, respect- ively, the methylation levels were similar to those in healthy women. In order to underpin our finding on the triple negative tumor, we determined the methylation status of CDKN2A exon 2 in the triple negative breast cancer cell line MDA-MB-231 and compared it with that obtained for the luminal A cell line MCF-7 and the lu- minal B cell line ZR-75-1. In line with our results for
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Die Beeinflussung des complexierten prostatspezifischen Antigens (c-PSA) durch mechanische und entzündliche Einflüsse

Die Beeinflussung des complexierten prostatspezifischen Antigens (c-PSA) durch mechanische und entzündliche Einflüsse

Während sich nach Prostatabiopsie ein signifikanter t –PSA Anstieg und eine minimale, aber statistisch signifikante c – PSA – Erhöhung zeigte, war nach flexibler Cystoskopi[r]

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PD-L1 Expression on Tumor Cells Is Associated With a Poor Outcome in a Cohort of Caucasian Nasopharyngeal Carcinoma Patients

PD-L1 Expression on Tumor Cells Is Associated With a Poor Outcome in a Cohort of Caucasian Nasopharyngeal Carcinoma Patients

Ma et al. reported that ≥1% PD-L1 expression was present in 40% TC and in 22.2% TILs, while no effect on OS or DFS was shown ( 23 ). Such a low expression rate of PD-L1 has also been observed in some retrospective studies, with levels of 20– 40% ( 18 , 24 – 26 ). On the other hand, several retrospective studies have reported PD-L1 positivity and high PD-L1 expression rates in up to 70–100 and 34–46% of NPC tumor samples, respectively ( 14 , 16 , 17 , 27 , 28 ). In our analysis, the PD-L1 positivity rate was 83%, which is in line with existing literature and similar to that in an Asian population.
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Anreicherung und Reinigung eines löslichen Antigens aus Maul-und Klauenseuche-infizierten Hühnerembryonen 

Anreicherung und Reinigung eines löslichen Antigens aus Maul-und Klauenseuche-infizierten Hühnerembryonen 

wurde. Elektrophoretisch wanderte die antigene Aktivität unserer Präparate mit einem Gradienten, dessen Wanderungsgeschwindigkeit in 0,1-ionaler Kochsalz- lösung vom pn 7,2 — 6,0 • 10~[r]

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Die molekulare Basis der RH-Haplotypen mit schwacher Expression des Antigens D

Die molekulare Basis der RH-Haplotypen mit schwacher Expression des Antigens D

3. Allen FH, Anstee DJ, Bird GWG, Brodheim E, Contreras M, Crookston M, Engelfriet CP, Freiesleben E, Gavrilov OK, Giles C, Högman CF, Issitt PD, Jorgensen J, Kornstad L, Leikola J, Lewis M, Lothe F, Marsh WL, Moore BPL, Morel P, Moulds JJ, Nordhagen R, Rosenfield RE, Rubinstein P, Sabo B, Salmon C, Seidl S, Shows TB, Smythe SM, Tippett PA, Walker RH und Yasuda J (1982) ISBT working party on terminology for red cell surface antigens. Preliminary report. Vox Sang 42: 164-165

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