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1.
Biomaterials ; 220: 119417, 2019 11.
Article in English | MEDLINE | ID: mdl-31419588

ABSTRACT

To improve the efficacy of cancer vaccines we aimed to modulate the suppressive tumor microenvironment. In this study, the potential of intratumoral immune modulation with poly (I:C), Resiquimod (R848) and CCL20 (MIP3α) was explored. Biodegradable polymeric nanoparticles were used as delivery vehicles for slow and sustained release of these drugs in the tumor area and were combined with specific immunotherapy based on therapeutic peptide vaccination in two aggressive murine carcinoma and lymphoma tumor models. Whereas nanoparticle delivery of poly (I:C) or R848 improved therapeutic efficacy, the combination with MIP3α remarkably potentiated the cancer vaccine antitumor effects. The long-term survival increased to 75-100% and the progression free survival nearly doubled on mice with established large carcinoma tumors. The potent adjuvant effects were associated with lymphoid and myeloid population alterations in the tumor and tumor-draining lymph node. In addition to a significant influx of macrophages into the tumor, the phenotype of the suppressor tumor-associated macrophages shifted towards an acute inflammatory phenotype in the tumor-draining lymph node. Overall, these data show that therapeutic cancer vaccines can be potentiated by the combined nanoparticle mediated co-delivery of poly (I:C), R848 and MIP3α, which indicates that a more favorable milieu for cancer fighting immune cells is created for T cells induced by therapeutic cancer vaccines.


Subject(s)
Biocompatible Materials/chemistry , Cancer Vaccines/therapeutic use , Immunologic Factors/administration & dosage , Nanoparticles/chemistry , Adjuvants, Immunologic/administration & dosage , Adjuvants, Immunologic/pharmacology , Animals , Cell Line, Tumor , Dendritic Cells/drug effects , Dendritic Cells/metabolism , Drug Delivery Systems , Endocytosis/drug effects , Imidazoles/administration & dosage , Immunologic Factors/pharmacology , Interleukin-12/biosynthesis , Lymph Nodes/drug effects , Lymph Nodes/pathology , Mice, Inbred C57BL , Poly I-C/administration & dosage , Poly I-C/pharmacology , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Progression-Free Survival , Survival Analysis , Treatment Outcome , Tumor Microenvironment/drug effects , Vaccination
2.
Curr Pharm Des ; 23(13): 1985-1992, 2017.
Article in English | MEDLINE | ID: mdl-28003012

ABSTRACT

The induction of immune tolerance towards self-antigens presents as a viable future strategy in the treatment of auto-immune diseases, including vasculitis and multiple sclerosis (MS). As specific targets are currently lacking for vasculitis due to incomplete understanding of the pathologies underlying this disease, current treatment options are based on modalities that induce general immune suppression. However, many immune suppressants used in the clinic are known to display wide biodistribution and are thus often accompanied by several adverse effects. Nano-vehicles (NVs) possess the ability to overcome such limitations by enabling more specific delivery of their content through modifications with targeting moieties. In this review, we describe the latest insights in the pathology of vasculitis that may function as potential targets for NV carrier systems, allowing more specific delivery of currently used immune suppressants. In addition, we describe the existing strategies to induce artificial immune tolerance and explore the feasibility of inducing regulatory T cell (Treg) mediated tolerance for MS, possibly mediated by NVs.


Subject(s)
Drug Delivery Systems , Multiple Sclerosis/drug therapy , Nanomedicine , Nanoparticles/chemistry , Vasculitis/drug therapy , Animals , Drug Carriers/chemistry , Humans , Multiple Sclerosis/immunology , T-Lymphocytes, Regulatory/immunology , Vasculitis/immunology
3.
Connect Tissue Res ; 56(2): 153-60, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25689091

ABSTRACT

Joints consist of different tissues, such as bone, cartilage and synovium, which are at risk for multiple diseases. The current imaging modalities, such as magnetic resonance imaging, Doppler ultrasound, X-ray, computed tomography and arthroscopy, lack the ability to detect disease activity before the onset of anatomical and significant irreversible damage. Optical in vivo imaging has recently been introduced as a novel imaging tool to study the joint and has the potential to image all kinds of biological processes. This tool is already exploited in (pre)clinical studies of rheumatoid arthritis, osteoarthritis and cancer. The technique uses fluorescent dyes conjugated to targeting moieties that recognize biomarkers of the disease. This review will focus on these new imaging techniques and especially where Near Infrared (NIR) fluorescence imaging has been used to visualize diseases of the joint. NIR fluorescent imaging is a promising technique which will soon complement established radiological, ultrasound and MRI imaging in the clinical management of patients with respect to early disease detection, monitoring and improved intervention.


Subject(s)
Arthritis, Rheumatoid/pathology , Bone and Bones/pathology , Joints/pathology , Osteoarthritis/pathology , Animals , Arthritis, Rheumatoid/diagnosis , Early Diagnosis , Humans , Magnetic Resonance Imaging/methods , Spectroscopy, Near-Infrared
6.
J Clin Pathol ; 56(11): 866-7, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14600135

ABSTRACT

A 56 year old man with previously unsuspected recurrence of squamous cell carcinoma of the oesophagus presented with dyspnoea. Bronchoscopy and computed tomography suggested bronchopneumonic changes with an infectious cause. He suffered a rapidly deteriorating course and died despite active treatment, including antibiotics and mechanical ventilation. Necropsy revealed a florid pulmonary tumour microembolism mimicking alveolitis. No bronchopneumonia was seen. The emboli arose from loosely attached tumour vegetations in the tricuspid valve. In a patient with known malignancy, tumour microembolism should be considered as an uncommon cause of rapid respiratory failure, refractory to antibiotic treatment.


Subject(s)
Lung Neoplasms/diagnosis , Lung Neoplasms/secondary , Neoplastic Cells, Circulating/pathology , Pneumonia/diagnosis , Pulmonary Embolism/diagnosis , Carcinoma, Squamous Cell/complications , Diagnosis, Differential , Esophageal Neoplasms/complications , Fatal Outcome , Humans , Male , Middle Aged , Pulmonary Alveoli , Pulmonary Embolism/etiology
7.
Biotechniques ; 34(5): 1082-6, 1088-9, 2003 May.
Article in English | MEDLINE | ID: mdl-12765035

ABSTRACT

Oligonucleotide arrays capable of detecting single nucleotide polymorphisms (SNPs) from amplified nucleic acid have many applications. The expected SNP is usually placed approximately in the center of the probe to ensure the maximum shift in Tm between complementary and SNP sequences. Unfortunately, different short probes (< 30 bases) selected using widely accepted criteria do not perform consistently in this type of assay. Here we present a systematic study on the effect of secondary structure on the ability of oligonucleotide probes to detect an SNP, using real-time array monitoring of a porous microarray substrate that incorporates a novel intra-array mixing system. These results demonstrate that, although positioning of an SNP in the middle of the probe is highly destabilizing, the effect of stable secondary structure on the signal obtained is so dramatic that such probes may be very insensitive. Therefore, if the SNP flanking sequence contains significant secondary structure, then more sensitive probes with good specificity may be obtained by positioning the mutation towards one end of the probe.


Subject(s)
DNA Probes/chemistry , DNA-Directed RNA Polymerases/genetics , Membranes, Artificial , Nucleic Acid Conformation , Oligonucleotide Array Sequence Analysis/instrumentation , Oligonucleotide Array Sequence Analysis/methods , Polymorphism, Single Nucleotide/genetics , Artifacts , DNA Probes/classification , Equipment Design , Equipment Failure Analysis , Porosity , Reproducibility of Results , Sensitivity and Specificity
8.
J Clin Pathol ; 55(12): 951-4, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12461066

ABSTRACT

AIMS: To review 25 cases of breast hamartoma and discuss the pathological criteria, and the usefulness of imaging modalities, fine needle aspiration cytology (FNAC), and needle core biopsy in the diagnosis. METHODS: The hamartomas were assessed for interlobular fibrotic stroma, stromal adipose tissue content, pseudo-angiomatous stromal hyperplasia, and epithelial changes (hyperplasia, adenosis or apocrine metaplasia, and cyst formation). All imagings, previous FNACs, and biopsies were also reviewed. RESULTS: Imaging (mammography, ultrasound, and magnetic resonance imaging) was performed in 18 cases, and mostly showed encapsulated masses with a heterogeneous appearance. Microscopically, all hamartomas demonstrated good demarcation with fibrous tissue condensation. Adipose tissue was noted in all cases (5-90%; mean, 31%), and interlobular fibrosis in 21 cases. Benign epithelial hyperplasia occurred in 10 cases, and pseudo-angiomatous stromal hyperplasia or cystic ducts in eight cases each. Apocrine metaplasia, calcification, stromal giant cells, and adenosis occurred in four cases or less. Two cases showed coexisting ductal carcinoma in situ limited to within the hamartoma. Needle core biopsies (four cases) and FNAC (14 cases) were largely insufficient, inconclusive, or non-specific. CONCLUSIONS: Hamartomas do not possess specific diagnostic histological features. The role of FNAC and needle core biopsy in making the diagnosis is limited, and requires clinical and radiological correlation to avoid underdiagnosis.


Subject(s)
Breast Diseases/diagnosis , Hamartoma/diagnosis , Adult , Aged , Biopsy, Needle/methods , Breast Diseases/diagnostic imaging , Breast Diseases/pathology , Female , Hamartoma/diagnostic imaging , Hamartoma/pathology , Humans , Mammography , Middle Aged , Retrospective Studies , Ultrasonography, Mammary
9.
Diagn Mol Pathol ; 10(4): 223-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11763312

ABSTRACT

Epstein-Barr virus (EBV) genome can be found in many malignant tumors in China. Previous data of interphase cytogenetics, by comparative genomic hybridization and/or fluorescence in situ hybridization, on nasopharyngeal carcinomas and natural killer cell-type non-Hodgkin lymphomas in Hong Kong have noted gains in chromosome 11. This study compares the frequency of chromosome 11 copy number gains in three different types of EBV-associated tumors in Hong Kong. Using alpha-satellite probes, the authors studied by fluorescence in situ hybridization 31 EBV-positive tumors comprising 10 EBV-positive gastric carcinomas, 8 lung lymphoepithelioma-like carcinomas, and 13 non-Hodgkin lymphomas. Trisomy or polysomy 11 was detected in 10 of 10 (100%) EBV-positive gastric carcinomas, 6 of 8 (75%) lung lymphoepithelioma-like carcinomas, and 4 of 13 (30.8%) non-Hodgkin lymphomas. Compared with the EBV-positive gastric carcinomas, the 10 EBV-negative gastric carcinomas that were also studied showed chromosome 11 copy number gains in 3 of 10 (30%), a significantly lower frequency. The authors conclude that gains in chromosome 11 are common in EBV-associated malignancies in Hong Kong, with the strongest association found in gastric carcinoma. There seems to be differences between EBV-associated tumors of different locations, and between gastric carcinomas with and without EBV.


Subject(s)
Chromosomes, Human, Pair 11 , Epstein-Barr Virus Infections/genetics , Gene Dosage , Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Aneuploidy , Carcinoma/genetics , Carcinoma/pathology , Carcinoma/virology , DNA, Neoplasm/analysis , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/pathology , Female , Herpesvirus 4, Human/genetics , Herpesvirus 4, Human/isolation & purification , Humans , In Situ Hybridization, Fluorescence , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/virology , Lymphoma, Non-Hodgkin/genetics , Lymphoma, Non-Hodgkin/pathology , Lymphoma, Non-Hodgkin/virology , Male , Middle Aged , Neoplasms/pathology , Neoplasms/virology , Polymerase Chain Reaction , RNA, Viral/analysis , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Stomach Neoplasms/virology
10.
Lett Appl Microbiol ; 30(1): 75-9, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10728566

ABSTRACT

Possession of mRNA is indicative of cell viability. RTPCR is not appropriate for mRNA detection as it cannot unambiguously detect mRNA in a DNA background. The alternative amplification technique, NASBA, avoids the disadvantages of RTPCR. We have devised a method for detection of viable Salmonella enterica. This involves NASBA amplification of mRNA transcribed from the dnaK gene. Amplification of mRNA extracted from viable and heat-killed cells from the same population produced consistent and highly significant (P > 0.01) differences between the respective signals. The signal obtained from viable cells was completely eradicated by RNase treatment, while PCR amplification of treated and untreated samples was unaffected, indicating that NASBA was unaffected by background DNA.


Subject(s)
Salmonella enterica/isolation & purification , DNA Primers , DNA, Bacterial/genetics , Nucleic Acid Amplification Techniques , Polymerase Chain Reaction/methods , RNA, Bacterial/analysis , RNA, Messenger/analysis , RNA, Messenger/isolation & purification , Reproducibility of Results , Ribonucleases , Salmonella enterica/genetics
11.
Am J Pathol ; 152(1): 11-6, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9422517

ABSTRACT

Fifteen cases of high grade primary gastric non-Hodgkin's lymphomas were studied using comparative genomic hybridization (CGH) and/or fluorescence in situ hybridization (FISH) techniques. A total of 10 cases of diffuse large cell lymphoma (DLCL) with no histologically identifiable or previous history of low grade mucosa-associated lymphoid tissue (MALT) lymphoma components were examined, four by CGH and validated by FISH, and the remaining six by FISH alone. All 10 tumors showed gains in chromosome 12. Other recurring CGH findings in DLCL included copy number gains of 1q and deletions of 6q. Five cases of high grade tumors with low grade MALT components (HGM) were also examined, three by CGH and validated by FISH and two by FISH only. Only one in five HGM showed gains of chromosome 12. Other recurring CGH findings in HGM included +7q and +11q. We conclude that high grade gastric lymphomas of DLCL type were associated with gains in chromosome 12. The change was much less frequent (P < 0.01) in the HGM type, which had a percentage similar to that observed in previously reported cytogenetics/FISH studies on low grade MALT lymphomas. Our findings suggested that many DLCL were not derived from transformation of low grade MALT lymphomas.


Subject(s)
Chromosomes, Human, Pair 12 , Gene Dosage , Lymphoma, Large B-Cell, Diffuse/genetics , Stomach Neoplasms/genetics , Adult , Aged , Female , Gene Deletion , Humans , In Situ Hybridization, Fluorescence , Male , Middle Aged , Nucleic Acid Hybridization
12.
J Glaucoma ; 6(2): 117-22, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9098820

ABSTRACT

PURPOSE: To examine intra- and interrater agreement when analyzing cumulative defect curves. Cumulative defect (Bebié) curves provide a graphical representation of the visual field and allow a subjective classification of diffuse and localized loss. METHODS: We used 75 Humphrey 30-2 visual field tests, randomly chosen from a database of 782 fields of 113 patients with open-angle glaucoma. Cumulative defect curves were generated and randomly arranged into five sets, with each set containing the 75 curves in a unique sequence. Five raters (two experienced and three inexperienced) rated each set and classified each curve as showing diffuse loss, localized loss, both diffuse and localized loss, or no loss. The intra- and interrater agreement in rating the curves was then analyzed. RESULTS: Intrarater agreement ranged from 73.3-88.0% for perfect rater agreement, with 5 identical ratings. Agreement for experienced versus inexperienced raters gave similar results (means: 84.0% and 77.8%, respectively, for perfect agreement). Interrater agreement for each set, evaluated by the kappa statistic, was substantial for all 5 sets (0.65-0.71). Kappa values for each set were comparable for experienced and inexperienced raters (0.72-0.83 and 0.59-0.69 respectively). CONCLUSIONS: Analyzing the nature of visual field loss using the cumulative defect curve is simple to learn and provides high intrarater agreement as well as substantial interrater agreement.


Subject(s)
Glaucoma, Open-Angle/diagnosis , Vision Disorders/diagnosis , Visual Field Tests , Visual Fields , Glaucoma, Open-Angle/physiopathology , Humans , Observer Variation , Prospective Studies , Random Allocation , Vision Disorders/classification , Vision Disorders/physiopathology , Visual Acuity , Visual Perception
13.
Ophthalmology ; 104(3): 532-8, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9082285

ABSTRACT

PURPOSE: The authors determined the frequency of repeatable diffuse loss as the only form of visual field damage in patients with early to moderate open-angle glaucoma in a prospective follow-up study. METHODS: The study contained 113 patients (median age, 64 years; range, 17-89 years) who were tested at 6-month intervals with program 30-2 of the Humphrey Field Analyzer (Humphrey Instruments Inc., San Leandro, CA). Although the inclusion criterion for visual acuity was > or = 20/40, on entry, 94 (83.2%) patients had an acuity of > or = 20/25. Cumulative defect curves were generated for all visual fields (median per patient, 7; range, 4-9). After randomizing the order and removing all patient information, two observers independently rated each visual field as being "normal" or showing "diffuse," "localized," or "diffuse and localized" loss. We defined repeatable diffuse loss as occurring when at least two thirds of the number of fields in the follow-up were classified as "diffuse." RESULTS: Fourteen patients (12.4%) had repeatable diffuse loss according to the cumulative defect curves. After reviewing their clinical charts, we excluded six of these patients because of early lens changes despite good visual acuity and three because of a suggestion of localized loss (on pattern deviation probability plots) in addition to the predominantly diffuse loss. The remaining five (4.4%) patients had repeatable diffuse loss that was due solely to open-angle glaucoma. CONCLUSION: Although diffuse visual field loss is exaggerated by factors other than glaucoma in the majority of patients, it can occur repeatedly in a small number of patients as the only sign of visual field damage.


Subject(s)
Glaucoma, Open-Angle/complications , Vision Disorders/etiology , Visual Fields , Adolescent , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Fundus Oculi , Humans , Male , Middle Aged , Optic Disk/pathology , Prospective Studies , Recurrence , Visual Acuity , Visual Field Tests
14.
Q J Exp Physiol ; 74(4): 553-6, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2798764

ABSTRACT

Monolayers of canine kidney (MDCK) and human lower intestinal (T84 and HCT-8) cell lines generated significant transepithelial electrical resistance (700-5000 omega cm2). Electrical integrity was maintained upon acidification of the apical and/or basolateral surfaces to pH 3.0, and this was associated with increased transepithelial electrical resistance, and generation of a potential difference at pH less than 4.5. These results indicate that resistance to acid is a general phenomenon of epithelial layers, and that monolayers of epithelial cells, including those of human origin, are a homogeneous and simple model for studying epithelial barrier function in vitro.


Subject(s)
Adenocarcinoma/physiopathology , Cecal Neoplasms/physiopathology , Colon/physiology , Kidney/physiology , Animals , Cell Line , Cells, Cultured , Dogs , Electric Conductivity , Epithelial Cells , Humans , Hydrogen-Ion Concentration , Membrane Potentials
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