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1.
Cancer Drug Resist ; 6(3): 611-641, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37842241

RESUMO

The development of immune checkpoint blockade (ICB) therapies has been instrumental in advancing the field of immunotherapy. Despite the prominence of these treatments, many patients exhibit primary or acquired resistance, rendering them ineffective. For example, anti-programmed cell death protein 1 (anti-PD-1)/anti-programmed cell death ligand 1 (anti-PD-L1) treatments are widely utilized across a range of cancer indications, but the response rate is only 10%-30%. As such, it is necessary for researchers to identify targets and develop drugs that can be used in combination with existing ICB therapies to overcome resistance. The intersection of cancer, metabolism, and the immune system has gained considerable traction in recent years as a way to comprehensively study the mechanisms that drive oncogenesis, immune evasion, and immunotherapy resistance. As a result, new research is continuously emerging in support of targeting metabolic pathways as an adjuvant to ICB to boost patient response and overcome resistance. Due to the plethora of studies in recent years highlighting this notion, this review will integrate the relevant articles that demonstrate how tumor-derived alterations in energy, amino acid, and lipid metabolism dysregulate anti-tumor immune responses and drive resistance to anti-PD-1/PD-L1 therapy.

2.
Cancers (Basel) ; 15(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37296940

RESUMO

Ibrutinib is a first-in-class Bruton's tyrosine kinase inhibitor approved for the treatment of various B-cell malignancies and chronic graft-versus-host disease. We evaluated the safety and efficacy of ibrutinib, alone or combined with standard-of-care regimens, in adults with advanced urothelial carcinoma (UC). Once-daily ibrutinib was administered orally at 840 mg (single-agent or with paclitaxel) or at 560 mg (with pembrolizumab). Phase 1b determined the recommended phase 2 dose (RP2D) of ibrutinib, and phase 2 assessed progression-free survival (PFS), overall response rate (ORR), and safety. Thirty-five, eighteen, and fifty-nine patients received ibrutinib, ibrutinib plus pembrolizumab, and ibrutinib plus paclitaxel at the RP2D, respectively. Safety profiles were consistent with those of the individual agents. The best-confirmed ORRs were 7% (two partial responses) with single-agent ibrutinib and 36% (five partial responses) with ibrutinib plus pembrolizumab. Median PFS was 4.1 months (range, 1.0-37.4+) with ibrutinib plus paclitaxel. The best-confirmed ORR was 26% (two complete responses). In previously treated patients with UC, ORR was higher with ibrutinib plus pembrolizumab than with either agent alone (historical data in the intent-to-treat population). ORR with ibrutinib plus paclitaxel was greater than historical values for single-agent paclitaxel or ibrutinib. These data warrant further evaluation of ibrutinib combinations in UC.

3.
Cancer Immunol Res ; 11(6): 732-746, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37023414

RESUMO

The development of immune checkpoint-based immunotherapies has been a major advancement in the treatment of cancer, with a subset of patients exhibiting durable clinical responses. A predictive biomarker for immunotherapy response is the preexisting T-cell infiltration in the tumor immune microenvironment (TIME). Bulk transcriptomics-based approaches can quantify the degree of T-cell infiltration using deconvolution methods and identify additional markers of inflamed/cold cancers at the bulk level. However, bulk techniques are unable to identify biomarkers of individual cell types. Although single-cell RNA sequencing (scRNA-seq) assays are now being used to profile the TIME, to our knowledge there is no method of identifying patients with a T-cell inflamed TIME from scRNA-seq data. Here, we describe a method, iBRIDGE, which integrates reference bulk RNA-seq data with the malignant subset of scRNA-seq datasets to identify patients with a T-cell inflamed TIME. Using two datasets with matched bulk data, we show iBRIDGE results correlated highly with bulk assessments (0.85 and 0.9 correlation coefficients). Using iBRIDGE, we identified markers of inflamed phenotypes in malignant cells, myeloid cells, and fibroblasts, establishing type I and type II interferon pathways as dominant signals, especially in malignant and myeloid cells, and finding the TGFß-driven mesenchymal phenotype not only in fibroblasts but also in malignant cells. Besides relative classification, per-patient average iBRIDGE scores and independent RNAScope quantifications were used for threshold-based absolute classification. Moreover, iBRIDGE can be applied to in vitro grown cancer cell lines and can identify the cell lines that are adapted from inflamed/cold patient tumors.


Assuntos
Neoplasias , Análise da Expressão Gênica de Célula Única , Humanos , RNA-Seq/métodos , Perfilação da Expressão Gênica/métodos , Linfócitos T , Biomarcadores , Análise de Célula Única/métodos , Microambiente Tumoral/genética
4.
Ulus Travma Acil Cerrahi Derg ; 28(9): 1258-1269, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36043915

RESUMO

BACKGROUND: This study was aimed to evaluate the injury characteristics, causes, results, and hospital charges in cases of occupational accidents that were reported to judicial authorities using trauma scores. METHODS: The study was performed after obtaining permission from the judicial authorities and approval from the local ethics committee. All occupational accident cases that were reported to the judicial authorities in Bolu Province between 2015 and 2019 were included in the study. The groups were compared with the Chi-Square test, Mann-Whitney U Test, and the Kruskal-Wallis Test. P<0.05 was considered statistically significant. RESULTS: This study included 3599 cases. The majority of the cases (74.70%) were male, with a mean age of 34.90±10.50 years. Occupational accidents occurred most frequently between 8 and 16 h (n=1982; 55.10%), on Friday (n=595, 16.53%), in April (n=356; 9.89%), and in spring (n=971; 26.98%). Occupational accident-related death occurred in 29 cases (0.8%). The most common injury due to occupational accidents occurred in the food industry (n=1256, 34.90%). Blunt object injury (n=1112, 30.90%) was the most common type of occupational accident; and the upper extremity (n=2049, 54.93%) was the most common injury localization. The mean Abbreviated Injury Scale of the cases was 0.94±0.74, the mean Injury Severity Score (ISS) was 1.79±4.47, and the mean New-Injury Severity Score (NISS) was 2.11±5.28. The means of ISS and NISS were statistically significantly higher for males, life-threatening injuries, work accidents in the Construction and Agriculture-Forestry sectors, fall from height, traffic accidents, and caught-in-machinery. The total hospital charge was 1,351,339.10 TL and its average was 380.30±2418.90 TL. The mean of treatment costs was significantly higher in the agriculture-forestry and construction sectors. CONCLUSION: The evaluation of all occupational accidents that are submitted to the jurisdiction on a provincial basis may provide more useful information in the prevention of work accidents. The use of trauma scores in the evaluation of occupational accidents is a useful argument for understanding the sectors and injury types that cause severe trauma. Furthermore, trauma scores may be an important predictor of hospital costs.


Assuntos
Ferimentos e Lesões , Ferimentos não Penetrantes , Acidentes por Quedas , Acidentes de Trabalho , Acidentes de Trânsito , Adulto , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
J Immunother ; 45(3): 167-179, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35034046

RESUMO

Budigalimab, a novel anti-PD-1 monoclonal antibody, demonstrated efficacy and biomarker pharmacodynamics in patients with head and neck squamous cell carcinoma (HNSCC) or non-small cell lung cancer (NSCLC) consistent with those reported by other PD-1 inhibitors. Herein are presented additional outcomes of biomarker analyses from the phase 1 study of budigalimab monotherapy in patients with HNSCC and NSCLC (NCT03000257). PD-1 inhibitor naive patients with advanced HNSCC (n=41) or NSCLC (n=40) received budigalimab intravenously at 250 mg every 2 weeks (Q2W) or 500 mg Q4W until progression. Archival tumor specimens were evaluated by immunohistochemistry for CD8 and tumor PD-1 ligand 1 (PD-L1) expression, RNA, and whole-exome sequencing. Serum and whole blood samples were acquired at baseline and at select on-treatment time points. As of October 2019, best overall response of 15% in HNSCC and 18% in NSCLC was observed in all treated patients; both cohorts reported responses in PD-L1+ and PD-L1- tumors. Treatment with budigalimab was associated with increases in multiple soluble biomarkers including interferon gamma-induced chemokines. Expanded overall T-cell counts, total CD8 T-cell counts, and percentages of CD8+CD45RA-CD62L- effector memory T cells were observed at cycle 1, day 15 in responders. Univariate analysis demonstrated an association between prolonged progression-free survival and higher tumor mutational burden/neoantigen load, smaller tumor size, lower platelet-lymphocyte ratios, lower CCL23, lower colony-stimulating factor 1, and lower interleukin-6 levels at baseline. The biomarker analysis presented herein identified additional early pharmacodynamic biomarkers associated with anti-PD-1 activity and improved clinical responses to budigalimab in patients with advanced HNSCC and NSCLC.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias de Cabeça e Pescoço , Neoplasias Pulmonares , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Antígeno B7-H1 , Biomarcadores , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico
7.
Br J Cancer ; 124(4): 760-769, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33139798

RESUMO

BACKGROUND: The balance between immune-stimulatory and immune-suppressive mechanisms in the tumour microenvironment is associated with tumour rejection and can predict the efficacy of immune checkpoint-inhibition therapies. METHODS: We consider the observed differences between the transcriptional programmes associated with cancer types where the levels of immune infiltration predict a favourable prognosis versus those in which the immune infiltration predicts an unfavourable prognosis and defined a score named Mediators of Immune Response Against Cancer in soLid microEnvironments (MIRACLE). MIRACLE deconvolves T cell infiltration, from inhibitory mechanisms, such as TGFß, EMT and PI3Kγ signatures. RESULTS: Our score outperforms current state-of-the-art immune signatures as a predictive marker of survival in TCGA (n = 9305, HR: 0.043, p value: 6.7 × 10-36). In a validation cohort (n = 7623), MIRACLE predicts better survival compared to other immune metrics (HR: 0.1985, p value: 2.73 × 10-38). MIRACLE also predicts response to checkpoint-inhibitor therapies (n = 333). The tumour-intrinsic factors inversely associated with the reported score such as EGFR, PRKAR1A and MAP3K1 are frequently associated with immune-suppressive phenotypes. CONCLUSIONS: The association of cancer outcome with the level of infiltrating immune cells is mediated by the balance of activatory and suppressive factors. MIRACLE accounts for this balance and predicts favourable cancer outcomes.


Assuntos
Neoplasias/genética , Neoplasias/imunologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Estudos de Coortes , Bases de Dados Genéticas , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Vigilância Imunológica , Linfócitos do Interstício Tumoral/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/mortalidade , Análise de Sobrevida
8.
J Immunother Cancer ; 8(1)2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32376723

RESUMO

BACKGROUND: An immune active cancer phenotype typified by a T helper 1 (Th-1) immune response has been associated with increased responsiveness to immunotherapy and favorable prognosis in some but not all cancer types. The reason of this differential prognostic connotation remains unknown. METHODS: To explore the contextual prognostic value of cancer immune phenotypes, we applied a multimodal pan-cancer analysis among 31 different histologies (9282 patients), encompassing immune and oncogenic transcriptomic analysis, mutational and neoantigen load and copy number variations. RESULTS: We demonstrated that the favorable prognostic connotation conferred by the presence of a Th-1 immune response was abolished in tumors displaying specific tumor-cell intrinsic attributes such as high transforming growth factor-beta (TGF-ß) signaling and low proliferation capacity. This observation was independent of mutation rate. We validated this observation in the context of immune checkpoint inhibition. WNT-ß catenin, barrier molecules, Notch, hedgehog, mismatch repair, telomerase activity and AMPK signaling were the pathways most coherently associated with an immune silent phenotype together with mutations of driver genes including IDH1/2, FOXA2, HDAC3, PSIP1, MAP3K1, KRAS, NRAS, EGFR, FGFR3, WNT5A and IRF7. CONCLUSIONS: This is the first systematic study demonstrating that the prognostic and predictive role of a bona fide favorable intratumoral immune response is dependent on the disposition of specific oncogenic pathways. This information could be used to refine stratification algorithms and prioritize hierarchically relevant targets for combination therapies.


Assuntos
Perfilação da Expressão Gênica/métodos , Imunidade/imunologia , Imunoterapia/métodos , Neoplasias/imunologia , Oncogenes/imunologia , Feminino , Humanos , Masculino , Neoplasias/mortalidade , Prognóstico , Análise de Sobrevida
9.
J Immunother Cancer ; 6(1): 50, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29871670

RESUMO

Anti-cancer immunotherapy is encountering its own checkpoint. Responses are dramatic and long lasting but occur in a subset of tumors and are largely dependent upon the pre-existing immune contexture of individual cancers. Available data suggest that three landscapes best define the cancer microenvironment: immune-active, immune-deserted and immune-excluded. This trichotomy is observable across most solid tumors (although the frequency of each landscape varies depending on tumor tissue of origin) and is associated with cancer prognosis and response to checkpoint inhibitor therapy (CIT). Various gene signatures (e.g. Immunological Constant of Rejection - ICR and Tumor Inflammation Signature - TIS) that delineate these landscapes have been described by different groups. In an effort to explain the mechanisms of cancer immune responsiveness or resistance to CIT, several models have been proposed that are loosely associated with the three landscapes. Here, we propose a strategy to integrate compelling data from various paradigms into a "Theory of Everything". Founded upon this unified theory, we also propose the creation of a task force led by the Society for Immunotherapy of Cancer (SITC) aimed at systematically addressing salient questions relevant to cancer immune responsiveness and immune evasion. This multidisciplinary effort will encompass aspects of genetics, tumor cell biology, and immunology that are pertinent to the understanding of this multifaceted problem.


Assuntos
Imunoterapia , Neoplasias , Humanos , Tolerância Imunológica , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/imunologia
10.
Emerg Top Life Sci ; 1(5): 411-419, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33525800

RESUMO

Immune oncology (IO) is challenged to expand its usefulness to a broader range of cancers. A second generation of IO agents acting beyond the realm of Checkpoint Inhibitor Therapy (CIT) is sought with the intent of turning immune-resistant cancers into appealing IO targets. The published literature proposes a profusion of models to explain cancer immune resistance to CIT that largely outnumber the immune landscapes and corresponding resistance mechanisms. In spite of the complex and contradicting models suggested to explain refractoriness to CIT, the identification of prevailing mechanisms and their targeting may not be as daunting as it at first appears. Here, we suggest that cancer cells go through a conserved evolutionary bottleneck facing a Two-Option Choice to evade recognition by the immune competent host: they can either adopt a clean oncogenic process devoid of immunogenic stimuli (immune-silent tumors) or display an entropic biology prone to immune recognition (immune-active tumors) but resilient to rejection thanks to the recruitment of compensatory immune suppressive processes. Strategies aimed at enhancing the effectiveness of CIT will be different according to the immune landscape targeted.

11.
Cancer Res ; 71(7): 2476-87, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21459804

RESUMO

More than one million prostate biopsies are performed in the United States every year. A failure to find cancer is not definitive in a significant percentage of patients due to the presence of equivocal structures or continuing clinical suspicion. We have identified gene expression changes in stroma that can detect tumor nearby. We compared gene expression profiles of 13 biopsies containing stroma near tumor and 15 biopsies from volunteers without prostate cancer. About 3,800 significant expression changes were found and thereafter filtered using independent expression profiles to eliminate possible age-related genes and genes expressed at detectable levels in tumor cells. A stroma-specific classifier for nearby tumor was constructed on the basis of 114 candidate genes and tested on 364 independent samples including 243 tumor-bearing samples and 121 nontumor samples (normal biopsies, normal autopsies, remote stroma, as well as stroma within a few millimeters of tumor). The classifier predicted the tumor status of patients using tumor-free samples with an average accuracy of 97% (sensitivity = 98% and specificity = 88%) whereas classifiers trained with sets of 100 randomly generated genes had no diagnostic value. These results indicate that the prostate cancer microenvironment exhibits reproducible changes useful for categorizing the presence of tumor in patients when a prostate sample is derived from near the tumor but does not contain any recognizable tumor.


Assuntos
Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , RNA Neoplásico/biossíntese , Idoso , Idoso de 80 Anos ou mais , Biópsia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , RNA Neoplásico/genética , Reprodutibilidade dos Testes , Células Estromais/patologia , Células Estromais/fisiologia
12.
Dev Dyn ; 239(11): 2813-27, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20882681

RESUMO

Mutations in the Drosophila variable nurse cells (vnc) gene result in female sterility and oogenesis defects, including egg chambers with too many or too few nurse cells. We show that vnc corresponds to Arrest Defective1 (Ard1) and encodes the catalytic subunit of NatA, the major N-terminal acetyl-transferase complex. While N-terminal acetylation is one of the most prevalent covalent protein modifications in eukaryotes, analysis of its role in development has been challenging since mutants that compromise NatA activity have not been described in any multicellular animal. Our data show that reduced ARD1 levels result in pleiotropic oogenesis defects including abnormal cyst encapsulation, desynchronized cystocyte division, disrupted nurse cell chromosome dispersion, and abnormal chorion patterning, consistent with the wide range of predicted NatA substrates. Furthermore, we find that loss of Ard1 affects cell survival/proliferation and is lethal for the animal, providing the first demonstration that this modification is essential in higher eukaryotes.


Assuntos
Acetiltransferases/metabolismo , Domínio Catalítico/fisiologia , Proteínas de Drosophila/metabolismo , Ovário/citologia , Ovário/enzimologia , Acetiltransferases/genética , Alelos , Animais , Western Blotting , Domínio Catalítico/genética , Drosophila , Proteínas de Drosophila/genética , Feminino , Imuno-Histoquímica , Reação em Cadeia da Polimerase
13.
Virology ; 361(1): 185-93, 2007 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-17175003

RESUMO

The L1 gene of human papillomavirus-18 (HPV-18) is consistently hypermethylated in cervical carcinomas, but frequently hypo- or unmethylated in exfoliated cells from asymptomatic patients. In precancerous lesions, L1 is sporadically hypermethylated, correlating with the severity of the neoplasia. In order to explore the potential of using L1 methylation as a workable biomarker for carcinogenic progression of HPV-18 infections in routinely taken samples, our aim was to develop methylation-detection techniques that were sensitive and rapid without being overly complex technically. Therein, we developed a methylation-specific PCR (MSP) through the design of primer sets that specifically amplify either methylated or unmethylated HPV-18 L1 DNA within bisulfite-modified sample DNA. Amplification of unmethylated and in vitro methylated HPV-18 DNA by MSP resulted in 2500 copies of either of the two L1 DNA species being detected, a satisfactory sensitivity considering that bisulfite treatment leads to the fragmentation of about 99% of sample DNA. The primers proved specific and did not generate false positive results at concentrations exceeding the lowest limit of detection by a factor of 400. DNA from carcinomas yielded PCR signals only with the methylation-specific primers, and not with primers specific for unmethylated L1 genes. The inverse result was obtained with DNA from precursor lesions that contained only hypomethylated DNA. High-grade precursor lesions and carcinomas that contained hyper- as well as hypomethylated L1 DNA yielded PCR signals with both primers. By developing a fluorescence based real-time PCR, we quantitatively analyzed samples with in vitro methylated and unmethylated L1 DNA, and could distinguish clinical samples with hyper- and hypomethylated DNA or mixtures of both DNAs. The methylation-specific and real-time PCR techniques permitted efficient HPV-18 L1 methylation analyses and open the door for larger-scale clinical studies where the utility of methylation status to predict the progression of HPV-18 infection and HPV-18 associated lesions is assessed.


Assuntos
Carcinoma/diagnóstico , Reação em Cadeia da Polimerase/métodos , Neoplasias do Colo do Útero/diagnóstico , Biomarcadores/análise , Proteínas do Capsídeo/genética , Carcinoma/virologia , Metilação de DNA , Primers do DNA , Progressão da Doença , Feminino , Genes Virais , Papillomavirus Humano 18/genética , Humanos , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/virologia , Proteínas Virais/genética
14.
Virology ; 349(1): 175-83, 2006 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16472835

RESUMO

Epigenetic transcriptional regulation plays an important role in the life cycle of human papillomaviruses (HPVs) and the carcinogenic progression of anogenital HPV associated lesions. We performed a study designed to assess the methylation status of the HPV-18 genome, specifically of the late L1 gene, the adjacent long control region (LCR), and part of the E6 oncogene in cervical specimens with a range of pathological diagnoses. In asymptomatic infections and infections with precancerous (precursor) lesions, HPV-18 DNA was mostly unmethylated, with the exception of four samples where hypermethylation of L1 was detected. In contrast, L1 sequences were strongly methylated in all cervical carcinomas, while the LCR and E6 remained unmethylated. HeLa cells, derived from a cervical adenocarcinoma, contain chromosomally integrated HPV-18 genomes. We found that L1 is hypermethylated in these cells, while the LCR and E6 are unmethylated. Treatment of HeLa cells with the methylation inhibitor 5-Aza-2'-deoxycytidine (5-Aza-CdR) led to the expected reduction of L1 methylation. After removal of 5-Aza-CdR, L1 methylation resumed and exceeded pretreatment levels. Unexpectedly, the LCR and E6 also became methylated under these conditions, albeit at lower levels than L1. We hypothesize that L1 is preferentially methylated after integration of the HPV genome into the cellular DNA, possibly since linearization prohibits its normal transcription, while the enhancer and promoter may be protected from methylation by transcription factors. Since our data suggest that HPV-18 L1 methylation can only be detected in carcinomas, except in some few precancerous lesions and asymptomatic infections, L1 methylation may constitute a powerful molecular marker for detecting this important step of neoplastic progression.


Assuntos
Biomarcadores Tumorais , Proteínas do Capsídeo/genética , Metilação de DNA , DNA Viral/metabolismo , Papillomaviridae/química , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Colo do Útero/virologia , Metilases de Modificação do DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Decitabina , Inibidores Enzimáticos/farmacologia , Feminino , Células HeLa/virologia , Humanos , Proteínas Oncogênicas Virais/genética , Papillomaviridae/isolamento & purificação , Provírus/química , Elementos Reguladores de Transcrição , Neoplasias do Colo do Útero/virologia , Proteínas Virais
15.
Microbiol Immunol ; 49(10): 931-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16237271

RESUMO

The goal of this study was to determine the role of lipooligosaccharide in the attachment of Moraxella catarrhalis to human pharyngeal epithelial cells. Strain 2951 and its P(k) mutant strain 2951 galE were used in this study. This study suggests that the P(k) epitope of LOS is not an adhesin for M. catarrhalis, but plays a crucial role by its surface charge in the initial stage of attachment.


Assuntos
Adesinas Bacterianas/fisiologia , Aderência Bacteriana/fisiologia , Células Epiteliais/microbiologia , Lipopolissacarídeos/metabolismo , Moraxella catarrhalis/patogenicidade , Faringe/microbiologia , Polissacarídeos Bacterianos/fisiologia , Linhagem Celular , Humanos , Moraxella catarrhalis/fisiologia , Faringe/citologia
16.
Microb Pathog ; 34(6): 261-5, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12782478

RESUMO

Streptococcus pneumoniae causes respiratory and other invasive infections. Increased resistance of this bacterium to antibiotics necessitates new approaches to the treatment of infections. Attachment of bacteria to human pharyngeal epithelial cells is the initial step in the pathogenesis of infection and S-carboxymethylcysteine (S-CMC) can modulate the attachment of Moraxella catarrhalis and nontypable Haemophilus influenzae to epithelial cells. Unlike these two, S. pneumoniae is gram-positive and has a well-defined capsule. Here we examined the effects of S-CMC on the attachment and detachment of S. pneumoniae to human pharyngeal epithelial cells in vitro. Treatment of these cells with S-CMC significantly reduced the number of attached S. pneumoniae. S-CMC also resulted in a significant increase in the detachment of already attached S. pneumoniae to epithelial cells. In addition, treatment of S. pneumoniae with S-CMC significantly reduced their ability to attach to epithelial cells, but not the number of viable bacteria. Our study shows that S-CMC modulates the attachment of S. pneumoniae to human pharyngeal epithelial cells by acting both on cells and bacteria.


Assuntos
Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Carbocisteína/farmacologia , Faringe/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Antibacterianos/metabolismo , Carbocisteína/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Masculino , Faringe/citologia , Streptococcus pneumoniae/crescimento & desenvolvimento , Streptococcus pneumoniae/patogenicidade
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