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1.
J Exp Med ; 219(6)2022 06 06.
Article in English | MEDLINE | ID: mdl-35472220

ABSTRACT

Improving the efficacy of immune checkpoint therapies will require a better understanding of how immune cells are recruited and sustained in tumors. Here, we used the photoconversion of the tumor immune cell compartment to identify newly entering lymphocytes, determine how they change over time, and investigate their egress from the tumor. Combining single-cell transcriptomics and flow cytometry, we found that while a diverse mix of CD8 T cell subsets enter the tumor, all CD8 T cells retained within this environment for more than 72 h developed an exhausted phenotype, revealing the rapid establishment of this program. Rather than forming tumor-resident populations, non-effector subsets, which express TCF-1 and include memory and stem-like cells, were continuously recruited into the tumor, but this recruitment was balanced by concurrent egress to the tumor-draining lymph node. Thus, the TCF-1+ CD8 T cell niche in tumors is highly dynamic, with the circulation of cells between the tumor and peripheral lymphoid tissue to bridge systemic and intratumoral responses.


Subject(s)
CD8-Positive T-Lymphocytes , Neoplasms , Humans , Immunotherapy , Lymphoid Tissue , T-Lymphocyte Subsets
2.
Health Technol Assess ; 26(16): 1-236, 2022 02.
Article in English | MEDLINE | ID: mdl-35229713

ABSTRACT

BACKGROUND: Femoroacetabular impingement syndrome is an important cause of hip pain in young adults. It can be treated by arthroscopic hip surgery or with physiotherapist-led conservative care. OBJECTIVE: To compare the clinical effectiveness and cost-effectiveness of hip arthroscopy with best conservative care. DESIGN: The UK FASHIoN (full trial of arthroscopic surgery for hip impingement compared with non-operative care) trial was a pragmatic, multicentre, randomised controlled trial that was carried out at 23 NHS hospitals. PARTICIPANTS: Participants were included if they had femoroacetabular impingement, were aged ≥ 16 years old, had hip pain with radiographic features of cam or pincer morphology (but no osteoarthritis) and were believed to be likely to benefit from hip arthroscopy. INTERVENTION: Participants were randomly allocated (1 : 1) to receive hip arthroscopy followed by postoperative physiotherapy, or personalised hip therapy (i.e. an individualised physiotherapist-led programme of conservative care). Randomisation was stratified by impingement type and recruiting centre using a central telephone randomisation service. Outcome assessment and analysis were masked. MAIN OUTCOME MEASURE: The primary outcome was hip-related quality of life, measured by the patient-reported International Hip Outcome Tool (iHOT-33) 12 months after randomisation, and analysed by intention to treat. RESULTS: Between July 2012 and July 2016, 648 eligible patients were identified and 348 participants were recruited. In total, 171 participants were allocated to receive hip arthroscopy and 177 participants were allocated to receive personalised hip therapy. Three further patients were excluded from the trial after randomisation because they did not meet the eligibility criteria. Follow-up at the primary outcome assessment was 92% (N = 319; hip arthroscopy, n = 157; personalised hip therapy, n = 162). At 12 months, mean International Hip Outcome Tool (iHOT-33) score had improved from 39.2 (standard deviation 20.9) points to 58.8 (standard deviation 27.2) points for participants in the hip arthroscopy group, and from 35.6 (standard deviation 18.2) points to 49.7 (standard deviation 25.5) points for participants in personalised hip therapy group. In the primary analysis, the mean difference in International Hip Outcome Tool scores, adjusted for impingement type, sex, baseline International Hip Outcome Tool score and centre, was 6.8 (95% confidence interval 1.7 to 12.0) points in favour of hip arthroscopy (p = 0.0093). This estimate of treatment effect exceeded the minimum clinically important difference (6.1 points). Five (83%) of six serious adverse events in the hip arthroscopy group were related to treatment and one serious adverse event in the personalised hip therapy group was not. Thirty-eight (24%) personalised hip therapy patients chose to have hip arthroscopy between 1 and 3 years after randomisation. Nineteen (12%) hip arthroscopy patients had a revision arthroscopy. Eleven (7%) personalised hip therapy patients and three (2%) hip arthroscopy patients had a hip replacement within 3 years. LIMITATIONS: Study participants and treating clinicians were not blinded to the intervention arm. Delays were encountered in participants accessing treatment, particularly surgery. Follow-up lasted for 3 years. CONCLUSION: Hip arthroscopy and personalised hip therapy both improved hip-related quality of life for patients with femoroacetabular impingement syndrome. Hip arthroscopy led to a greater improvement in quality of life than personalised hip therapy, and this difference was clinically significant at 12 months. This study does not demonstrate cost-effectiveness of hip arthroscopy compared with personalised hip therapy within the first 12 months. Further follow-up will reveal whether or not the clinical benefits of hip arthroscopy are maintained and whether or not it is cost-effective in the long term. TRIAL REGISTRATION: Current Controlled Trials ISRCTN64081839. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 16. See the NIHR Journals Library website for further project information.


In some people, the ball and the socket of the hip joint develop so that they do not fit together properly. This is called hip impingement, and is an important cause of hip and groin pain in young and middle-aged adults. Treatments include physiotherapy and surgery. Physiotherapy typically involves a programme of 6­10 outpatient consultations that aim to strengthen the muscles around the hip: we called this personalised hip therapy. Surgery can be carried out by a keyhole operation, called a hip arthroscopy, which aims to reshape the hip to prevent impingement. Surgery is normally followed by some physiotherapy. We performed a research study to compare the results of hip arthroscopy and personalised hip therapy in people with hip impingement. A total of 348 people with painful hip impingement in 23 hospitals in the UK agreed to take part. About half were treated with hip arthroscopy and half with personalised hip therapy. We used questionnaires to ask participants about pain in the hip and their ability to do everyday things at 6 months and 1 year after entering the study. At 2 and 3 years, we asked if patients required any additional treatments. We found that both groups improved, but those treated with hip arthroscopy improved a moderate amount more than those treated with personalised hip therapy. However, these improvements were not cost-effective compared with personalised hip therapy at 1 year. We need to see whether or not this difference continues after several years, but the results, so far, suggest that if a person has painful hip impingement, then hip arthroscopy offers greater improvements than personalised hip therapy.


Subject(s)
Femoracetabular Impingement , Adolescent , Arthroscopy , Cost-Benefit Analysis , Femoracetabular Impingement/surgery , Humans , Pain , Quality of Life , United Kingdom , Young Adult
3.
Nat Immunol ; 23(1): 50-61, 2022 01.
Article in English | MEDLINE | ID: mdl-34853448

ABSTRACT

NP105-113-B*07:02-specific CD8+ T cell responses are considered among the most dominant in SARS-CoV-2-infected individuals. We found strong association of this response with mild disease. Analysis of NP105-113-B*07:02-specific T cell clones and single-cell sequencing were performed concurrently, with functional avidity and antiviral efficacy assessed using an in vitro SARS-CoV-2 infection system, and were correlated with T cell receptor usage, transcriptome signature and disease severity (acute n = 77, convalescent n = 52). We demonstrated a beneficial association of NP105-113-B*07:02-specific T cells in COVID-19 disease progression, linked with expansion of T cell precursors, high functional avidity and antiviral effector function. Broad immune memory pools were narrowed postinfection but NP105-113-B*07:02-specific T cells were maintained 6 months after infection with preserved antiviral efficacy to the SARS-CoV-2 Victoria strain, as well as Alpha, Beta, Gamma and Delta variants. Our data show that NP105-113-B*07:02-specific T cell responses associate with mild disease and high antiviral efficacy, pointing to inclusion for future vaccine design.


Subject(s)
HLA-B7 Antigen/immunology , Immunodominant Epitopes/immunology , Nucleocapsid Proteins/immunology , SARS-CoV-2/immunology , T-Lymphocytes, Cytotoxic/immunology , Aged , Amino Acid Sequence , Antibodies, Viral/immunology , Antibody Affinity/immunology , COVID-19/immunology , COVID-19/pathology , Cell Line, Transformed , Female , Gene Expression Profiling , Humans , Immunologic Memory/immunology , Male , Middle Aged , Receptors, Antigen, T-Cell/immunology , Severity of Illness Index , Vaccinia virus/genetics , Vaccinia virus/immunology , Vaccinia virus/metabolism
4.
PLoS One ; 16(12): e0260954, 2021.
Article in English | MEDLINE | ID: mdl-34932587

ABSTRACT

Elimination of the binding of immunoglobulin Fc to Fc gamma receptors (FcγR) is highly desirable for the avoidance of unwanted inflammatory responses to therapeutic antibodies and fusion proteins. Many different approaches have been described in the literature but none of them completely eliminates binding to all of the Fcγ receptors. Here we describe a set of novel variants having specific amino acid substitutions in the Fc region at L234 and L235 combined with the substitution G236R. They show no detectable binding to Fcγ receptors or to C1q, are inactive in functional cell-based assays and do not elicit inflammatory cytokine responses. Meanwhile, binding to FcRn, manufacturability, stability and potential for immunogenicity are unaffected. These variants have the potential to improve the safety and efficacy of therapeutic antibodies and Fc fusion proteins.


Subject(s)
Antibody-Dependent Cell Cytotoxicity , Complement C1q/metabolism , Histocompatibility Antigens Class I/metabolism , Immunoglobulin Fc Fragments/metabolism , Immunoglobulin G/metabolism , Receptors, Fc/metabolism , Receptors, IgG/metabolism , Amino Acid Substitution , Antibody Affinity , Complement C1q/genetics , Complement C1q/immunology , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/immunology , Humans , Immunoglobulin Fc Fragments/genetics , Immunoglobulin Fc Fragments/immunology , Immunoglobulin G/genetics , Immunoglobulin G/immunology , Protein Binding , Protein Engineering , Receptors, Fc/genetics , Receptors, Fc/immunology , Receptors, IgG/genetics , Receptors, IgG/immunology
5.
Nat Immunol ; 21(11): 1336-1345, 2020 11.
Article in English | MEDLINE | ID: mdl-32887977

ABSTRACT

The development of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines and therapeutics will depend on understanding viral immunity. We studied T cell memory in 42 patients following recovery from COVID-19 (28 with mild disease and 14 with severe disease) and 16 unexposed donors, using interferon-γ-based assays with peptides spanning SARS-CoV-2 except ORF1. The breadth and magnitude of T cell responses were significantly higher in severe as compared with mild cases. Total and spike-specific T cell responses correlated with spike-specific antibody responses. We identified 41 peptides containing CD4+ and/or CD8+ epitopes, including six immunodominant regions. Six optimized CD8+ epitopes were defined, with peptide-MHC pentamer-positive cells displaying the central and effector memory phenotype. In mild cases, higher proportions of SARS-CoV-2-specific CD8+ T cells were observed. The identification of T cell responses associated with milder disease will support an understanding of protective immunity and highlights the potential of including non-spike proteins within future COVID-19 vaccine design.


Subject(s)
Antigens, Viral/immunology , Betacoronavirus/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Immunologic Memory/immunology , COVID-19 , COVID-19 Vaccines , Coronavirus Infections/immunology , Coronavirus Infections/pathology , Coronavirus Infections/prevention & control , Epitopes, T-Lymphocyte/immunology , Humans , Immunodominant Epitopes/immunology , Pandemics , Pneumonia, Viral/immunology , Pneumonia, Viral/pathology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/immunology , United Kingdom , Viral Vaccines/immunology
6.
bioRxiv ; 2020 Jun 08.
Article in English | MEDLINE | ID: mdl-32577665

ABSTRACT

COVID-19 is an ongoing global crisis in which the development of effective vaccines and therapeutics will depend critically on understanding the natural immunity to the virus, including the role of SARS-CoV-2-specific T cells. We have conducted a study of 42 patients following recovery from COVID-19, including 28 mild and 14 severe cases, comparing their T cell responses to those of 16 control donors. We assessed the immune memory of T cell responses using IFNγ based assays with overlapping peptides spanning SARS-CoV-2 apart from ORF1. We found the breadth, magnitude and frequency of memory T cell responses from COVID-19 were significantly higher in severe compared to mild COVID-19 cases, and this effect was most marked in response to spike, membrane, and ORF3a proteins. Total and spike-specific T cell responses correlated with the anti-Spike, anti-Receptor Binding Domain (RBD) as well as anti-Nucleoprotein (NP) endpoint antibody titre (p<0.001, <0.001 and =0.002). We identified 39 separate peptides containing CD4 + and/or CD8 + epitopes, which strikingly included six immunodominant epitope clusters targeted by T cells in many donors, including 3 clusters in spike (recognised by 29%, 24%, 18% donors), two in the membrane protein (M, 32%, 47%) and one in the nucleoprotein (Np, 35%). CD8+ responses were further defined for their HLA restriction, including B*4001-restricted T cells showing central memory and effector memory phenotype. In mild cases, higher frequencies of multi-cytokine producing M- and NP-specific CD8 + T cells than spike-specific CD8 + T cells were observed. They furthermore showed a higher ratio of SARS-CoV-2-specific CD8 + to CD4 + T cell responses. Immunodominant epitope clusters and peptides containing T cell epitopes identified in this study will provide critical tools to study the role of virus-specific T cells in control and resolution of SARS-CoV-2 infections. The identification of T cell specificity and functionality associated with milder disease, highlights the potential importance of including non-spike proteins within future COVID-19 vaccine design.

8.
Eye Contact Lens ; 44(3): 170-181, 2018 May.
Article in English | MEDLINE | ID: mdl-28727604

ABSTRACT

OBJECTIVE: Topical interleukin (IL)-1 receptor (R)1 blockade is therapeutically active in reducing signs and symptoms of dry eye disease. Herein, we describe in vitro and in vivo nonclinical Investigational New Drug (IND)-enabling studies of EBI-005, a novel protein chimera of IL-1ß and IL-1 receptor antagonist (IL-1Ra or anakinra) that potently binds IL-1R1 and blocks signaling. These studies provide an assessment of receptor affinity, drug bioavailability, immunogenic response, safety, and tolerability in mice and rabbits. METHODS: In vitro and in silico along with Good Laboratory Practices (GLP) and non-GLP in vivo studies in mice and rabbits assessed the topical ocular and systemic immunogenicity and toxicology of EBI-005. Animals were treated with EBI-005 once daily subcutaneously or four times daily by topical ocular administration for up to 6 weeks (with 2-week recovery phase). RESULTS: EBI-005 has 500 times higher affinity than anakinra to IL-1R1. Predictive immunogenicity testing suggested that EBI-005 is not more immunogenic. Systemic bioavailability of EBI-005 is low (1.4% in mice and 0.2% in rabbits) after topical ocular administration. EBI-005 penetrated into the anterior ocular tissues within 15 min of topical ocular administration. However, it is low or undetectable after 4 hr and does not form a depot after repeated topical ocular administration. EBI-005 was safe and well tolerated, and exposure to drug was maintained despite an antidrug antibody response after systemic administration, based on IND-enabling toxicology and safety pharmacology studies. CONCLUSIONS: Ocular doses of EBI-005 at 50 mg/mL in mice and rabbits totaling 0.15 mg/eye in mice and 1.5 mg/eye in rabbits, administered 4 times daily, did not produce adverse effects, and demonstrated excellent bioavailability in target tissues with low systemic exposure. In addition, immunogenic response to the drug did not cause adverse effects or diminish the drug's activity in most cases. The results support drug administration of the highest anticipated human clinical study dose of a 20 mg/mL solution (40 µL 3 times daily in each eye).


Subject(s)
Conjunctivitis, Allergic/drug therapy , Dry Eye Syndromes/drug therapy , Ophthalmic Solutions/therapeutic use , Proteins/therapeutic use , Receptors, Interleukin-1/antagonists & inhibitors , Administration, Topical , Animals , Disease Models, Animal , Immunoglobulin G/analysis , Immunoglobulin M/analysis , Interleukin 1 Receptor Antagonist Protein/metabolism , Male , Proteins/immunology , Rabbits
9.
Mol Ther ; 25(12): 2620-2634, 2017 Dec 06.
Article in English | MEDLINE | ID: mdl-28967558

ABSTRACT

Oncolytic virotherapy may be a means of improving the dismal prognosis of malignant brain tumors. The rat H-1 parvovirus (H-1PV) suppresses tumors in preclinical glioma models, through both direct oncolysis and stimulation of anticancer immune responses. This was the basis of ParvOryx01, the first phase I/IIa clinical trial of an oncolytic parvovirus in recurrent glioblastoma patients. H-1PV (escalating dose) was administered via intratumoral or intravenous injection. Tumors were resected 9 days after treatment, and virus was re-administered around the resection cavity. Primary endpoints were safety and tolerability, virus distribution, and maximum tolerated dose (MTD). Progression-free and overall survival and levels of viral and immunological markers in the tumor and peripheral blood were also investigated. H-1PV treatment was safe and well tolerated, and no MTD was reached. The virus could cross the blood-brain/tumor barrier and spread widely through the tumor. It showed favorable pharmacokinetics, induced antibody formation in a dose-dependent manner, and triggered specific T cell responses. Markers of virus replication, microglia/macrophage activation, and cytotoxic T cell infiltration were detected in infected tumors, suggesting that H-1PV may trigger an immunogenic stimulus. Median survival was extended in comparison with recent meta-analyses. Altogether, ParvOryx01 results provide an impetus for further H-1PV clinical development.


Subject(s)
Genetic Therapy , Genetic Vectors/genetics , Glioblastoma/genetics , Glioblastoma/therapy , H-1 parvovirus/genetics , Oncolytic Virotherapy , Oncolytic Viruses/genetics , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Female , Gene Expression , Genetic Therapy/adverse effects , Genetic Therapy/methods , Genetic Vectors/administration & dosage , Genetic Vectors/immunology , Glioblastoma/mortality , Glioblastoma/pathology , Humans , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Lymphocytes, Tumor-Infiltrating/pathology , Male , Middle Aged , Molecular Targeted Therapy , Oncolytic Virotherapy/adverse effects , Oncolytic Virotherapy/methods , Radiotherapy , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , T-Lymphocytes/pathology , Transgenes , Treatment Outcome
11.
Health Technol Assess ; 20(32): 1-172, 2016 04.
Article in English | MEDLINE | ID: mdl-27117505

ABSTRACT

BACKGROUND: Femoroacetabular impingement (FAI) is a syndrome of hip or groin pain associated with shape abnormalities of the hip joint. Treatments include arthroscopic surgery and conservative care. This study explored the feasibility of a randomised controlled trial to compare these treatments. OBJECTIVES: The objectives of this study were to estimate the number of patients available for a full randomised controlled trial (RCT); to explore clinician and patient willingness to participate in such a RCT; to develop consensus on eligibility criteria, surgical and best conservative care protocols; to examine possible outcome measures and estimate the sample size for a full RCT; and to develop trial procedures and estimate recruitment and follow-up rates. METHODS: Pre-pilot work: we surveyed all UK NHS hospital trusts (n = 197) to identify all FAI surgeons and to estimate how much arthroscopic FAI surgery they performed. We interviewed a purposive sample of 18 patients, 36 physiotherapists, 18 surgeons and two sports physicians to explore attitudes towards a RCT and used consensus-building methods among them to develop treatment protocols and patient information. Pilot RCT: we performed a pilot RCT in 10 hospital trusts. Patients were randomised to receive either hip arthroscopy or best conservative care and then followed up at 3, 6 and 12 months using patient-reported questionnaires for hip pain and function, activity level, quality of life, and a resource-use questionnaire. Qualitative recruitment intervention: we performed semistructured interviews with all researchers and clinicians involved in the pilot RCT in eight hospital trusts and recorded and analysed diagnostic and recruitment consultations with eligible patients. RESULTS: We identified 120 surgeons who reported treating at least 1908 patients with FAI by hip arthroscopy in the NHS in the financial year 2011/12. There were 34 hospital trusts that performed ≥ 20 arthroscopic FAI operations in the year. We found that clinicians were positive about a RCT: only half reported equipoise, but most said that they would be prepared to randomise patients. Patients strongly supported a RCT, but expressed concerns about its design; these were used to develop patient information for the pilot RCT. We developed a surgical protocol and showed that this could be used in a RCT. We developed a physiotherapy-led exercise-based package of best conservative care called 'personalised hip therapy' and showed that this was practicable. In the pilot RCT, we recruited 42 out of 60 eligible patients (70%) across nine sites. The mean duration and recruitment rate across all sites were 4.5 months and one patient per site per month, respectively. The lead site recruited for the longest period (9.3 months) and accrued the largest number of patients (2.1 patients per month). We recorded and analysed 84 diagnostic and recruitment consultations in 60 patients and used these to develop a model for an optimal recruitment consultation. We identified the International Hip Outcome Tool at 12 months as an appropriate outcome measure and estimated the sample size for a full trial as 344 participants: a number that could be recruited in 25 centres over 18 months. CONCLUSION: We have demonstrated that it is feasible to perform a RCT to establish the clinical effectiveness of hip arthroscopy compared with best conservative care for FAI. We have designed a full trial and developed and tested procedures for it, including an innovative approach to recruitment. We propose that a full trial be implemented. FUNDING: The National Institute for Health Research Health Technology Assessment programme.


Subject(s)
Arthroscopy/methods , Clinical Protocols , Femoracetabular Impingement/surgery , Hip Joint/physiopathology , Adult , Exercise Therapy/methods , Feasibility Studies , Female , Humans , Male , State Medicine , Surveys and Questionnaires , Technology Assessment, Biomedical , Treatment Outcome
12.
Clin Transl Allergy ; 4(1): 13, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24739743

ABSTRACT

Experimental in silico, in vitro, and rodent models for screening and predicting protein sensitizing potential are discussed, including whether there is evidence of new sensitizations and allergies since the introduction of genetically modified crops in 1996, the importance of linear versus conformational epitopes, and protein families that become allergens. Some common challenges for predicting protein sensitization are addressed: (a) exposure routes; (b) frequency and dose of exposure; (c) dose-response relationships; (d) role of digestion, food processing, and the food matrix; (e) role of infection; (f) role of the gut microbiota; (g) influence of the structure and physicochemical properties of the protein; and (h) the genetic background and physiology of consumers. The consensus view is that sensitization screening models are not yet validated to definitively predict the de novo sensitizing potential of a novel protein. However, they would be extremely useful in the discovery and research phases of understanding the mechanisms of food allergy development, and may prove fruitful to provide information regarding potential allergenicity risk assessment of future products on a case by case basis. These data and findings were presented at a 2012 international symposium in Prague organized by the Protein Allergenicity Technical Committee of the International Life Sciences Institute's Health and Environmental Sciences Institute.

13.
J Virol ; 83(14): 7361-4, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19386715

ABSTRACT

To study the role of CD8 T cells in the control of varicella-zoster virus (VZV) reactivation, we developed multimeric major histocompatibility complexes to identify VZV-specific CD8 T cells. Potential HLA-A2 binding peptides from the putative immediate-early 62 protein (IE62) of VZV were tested for binding, and peptides with sufficient binding capacity were used to generate pentamers. Patients with VZV reactivation following stem cell transplantation were screened with these pentamers, leading to the identification of the first validated class I-restricted epitope of VZV. In 42% of HLA-A2 patients following VZV reactivation, these IE62-ALW-A2 T cells could be detected ex vivo.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Herpes Zoster/immunology , Herpesvirus 3, Human/immunology , Postoperative Complications/immunology , Postoperative Complications/virology , Stem Cell Transplantation/adverse effects , Cohort Studies , HLA-A2 Antigen/immunology , Herpes Zoster/virology , Humans , Immediate-Early Proteins/immunology , Trans-Activators/immunology , Transplantation, Homologous/adverse effects , Transplantation, Homologous/immunology , Viral Envelope Proteins/immunology
14.
J Nat Prod ; 72(5): 876-83, 2009 May 22.
Article in English | MEDLINE | ID: mdl-20161135

ABSTRACT

A modified synthetic route to combretastatin D-2 (5) was devised in order to further evaluate its biological activity, for its conversion to phosphate prodrugs (25-28), and as a route to obtaining dihydro-combretastatin D-2 (42). A parallel first total synthesis of dihydro-combretastatin D-2 was completed, proceeding from a saturated 3-phenylpropionic ester intermediate via the Ullmann biaryl ether reaction (39-41). In contrast to the cancer cell growth inhibitory activity exhibited by combretastatin D-2, relatively minor structural modifications (41, 42) caused elimination of those properties.


Subject(s)
Antineoplastic Agents, Phytogenic/chemical synthesis , Antineoplastic Agents, Phytogenic/pharmacology , Bibenzyls/chemical synthesis , Bibenzyls/pharmacology , Lactones/chemical synthesis , Lactones/pharmacology , Phenyl Ethers/chemical synthesis , Phenyl Ethers/pharmacology , Prodrugs/chemical synthesis , Prodrugs/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Bibenzyls/chemistry , Crystallography, X-Ray , Drug Design , Drug Screening Assays, Antitumor , Lactones/chemistry , Molecular Structure , Phenyl Ethers/chemistry , Prodrugs/chemistry , Structure-Activity Relationship
15.
Arch Oral Biol ; 49(12): 1007-13, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15485643

ABSTRACT

OBJECTIVE: Unusual long-wave cycles in the position of an erupting human premolar were first noted by Trentini et al. [Trentini CJ, Brown WH, Paterson RL, Proffit WR. The application of Moire magnification to high precision studies of human premolar eruption. Arch Oral Biol 1995;40:623-9]. This report characterises them in detail and evaluates their significance relative to human tooth eruption. DESIGN: The magnitude and frequency of Trentini cycles were examined in high-resolution recordings of premolar eruption in patients without and with periapical infiltration of a vasoconstrictor or vasodilator, and the possibility of artifact due to the natural frequency of vibration of a tooth-PDL system or to building vibration was evaluated. RESULTS: The cycles are characterised by a magnitude of 1.3 +/- 0.5 microm and a frequency of 1.8 +/- 0.5 cycles per minute, with greater variation between than among subjects. They cannot be explained as a natural frequency phenomenon, and vibration from microseism is highly unlikely. The cycles disappear when blood flow to the periapical area of the tooth is interrupted and reappear when blood flow resumes. CONCLUSIONS: The cycles appear to reflect a physiologic rhythm, probably related to blood flow in the periodontal ligament. Because they are similar whether or not a tooth is erupting at a particular time, however, it appears that they are not a direct reflection of a blood flow-related eruption mechanism.


Subject(s)
Bicuspid/physiology , Tooth Eruption/physiology , Artifacts , Bicuspid/blood supply , Circadian Rhythm/physiology , Dental Equipment , Humans , Moire Topography/instrumentation , Regional Blood Flow/physiology , Signal Processing, Computer-Assisted , Vibration
16.
Hum Gene Ther ; 14(6): 577-90, 2003 Apr 10.
Article in English | MEDLINE | ID: mdl-12718767

ABSTRACT

Infusion of allogeneic, donor bone marrow (BM) can induce specific immunological unresponsiveness in vivo resulting in long-term acceptance of subsequent fully allogeneic, donor-type solid organ grafts, but this may be associated with graft-versus-host disease. We hypothesize that transfer of donor MHC gene(s) to recipient-type BM or hematopoietic stem cells would enable delivery of donor alloantigens to the recipient without the risk of graft-versus-host disease. This strategy could also potentially take advantage of linked suppression to induce specific unresponsiveness to additional alloantigens expressed by the solid organ graft. We found that infusion of 5 x 10(6) CBA (H-2(k)) recipient mouse BM cells transduced with a recombinant replication-defective retrovirus encoding either a single donor MHC class I or class II gene (H-2K(b) or H-2IA(b)) in combination with anti-CD4 monoclonal antibody resulted in long-term survival of C57BL/10 (H-2(b)) but not third-party NZW (H-2(z)) heart grafts. BM cells (3 x 10(3)) enriched for hematopoietic stem cells by sorting for c-Kit(+), lineage-negative cells, were able to induce long-term allograft survival in 50% of recipients after transduction with the vector encoding a single donor MHC class I gene. These results have important implications for future strategies to enhance clinical allograft survival by delivery of donor alloantigens.


Subject(s)
Bone Marrow Transplantation , Genes, MHC Class II , Genes, MHC Class I , Heart Transplantation/immunology , Isoantigens/immunology , Retroviridae/genetics , Transplantation Tolerance , 3T3 Cells , Animals , Bone Marrow Cells/physiology , Defective Viruses/genetics , Genetic Vectors , Graft Survival , Graft vs Host Disease/prevention & control , Heart Transplantation/pathology , Hematopoietic Stem Cells/chemistry , Mice , Mice, Inbred C57BL , Mice, Inbred CBA , Mice, Inbred NZB , Proto-Oncogene Proteins c-kit/analysis , Tissue Donors , Transduction, Genetic
17.
Transplantation ; 73(1 Suppl): S16-8, 2002 Jan 15.
Article in English | MEDLINE | ID: mdl-11810055

ABSTRACT

Alloantigen administration before transplantation, either alone or in combination with therapeutic agents that modulate the functional activity of the responding leukocytes, can be a powerful way of inducing specific unresponsiveness to alloantigens in vivo. In theory, any cell expressing one or more donor alloantigens has the ability to modulate the subsequent immune response to an allograft expressing the same molecules. However, not all sources of cells are equal in their ability to induce specific unresponsiveness. Understanding the molecular mechanisms that influence the way the outcome of the immune response to alloantigen develops, either activation or unresponsiveness to the triggering antigen, will enable the immune system to be manipulated more effectively for therapeutic purposes.


Subject(s)
Cell Transplantation , Isoantigens/immunology , Tissue Donors , Animals , Antibodies, Monoclonal/therapeutic use , CD4 Antigens/immunology , Graft Survival/physiology , Humans , Immune System/physiology , T-Lymphocytes/physiology , Transplantation Tolerance/physiology
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