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Racine JJ, Misherghi A, Dwyer JR, Maser R, Forte E, Bedard O, Sattler S, Pugliese A, Landry L, Elso C, Nakayama M, Mannering S, Rosenthal N, Serreze DV. HLA-DQ8 Supports Development of Insulitis Mediated by Insulin-Reactive Human TCR-Transgenic T Cells in Nonobese Diabetic Mice. J Immunol 2023; 211:1792-1805. [PMID: 37877672 PMCID: PMC10939972 DOI: 10.4049/jimmunol.2300303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 09/28/2023] [Indexed: 10/26/2023]
Abstract
In an effort to improve HLA-"humanized" mouse models for type 1 diabetes (T1D) therapy development, we previously generated directly in the NOD strain CRISPR/Cas9-mediated deletions of various combinations of murine MHC genes. These new models improved upon previously available platforms by retaining β2-microglobulin functionality in FcRn and nonclassical MHC class I formation. As proof of concept, we generated H2-Db/H2-Kd double knockout NOD mice expressing human HLA-A*0201 or HLA-B*3906 class I variants that both supported autoreactive diabetogenic CD8+ T cell responses. In this follow-up work, we now describe the creation of 10 new NOD-based mouse models expressing various combinations of HLA genes with and without chimeric transgenic human TCRs reactive to proinsulin/insulin. The new TCR-transgenic models develop differing levels of insulitis mediated by HLA-DQ8-restricted insulin-reactive T cells. Additionally, these transgenic T cells can transfer insulitis to newly developed NSG mice lacking classical murine MHC molecules, but expressing HLA-DQ8. These new models can be used to test potential therapeutics for a possible capacity to reduce islet infiltration or change the phenotype of T cells expressing type 1 diabetes patient-derived β cell autoantigen-specific TCRs.
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Affiliation(s)
| | - Adel Misherghi
- The Jackson Laboratory, Bar Harbor, ME
- College of the Atlantic, Bar Harbor, ME
| | | | | | | | | | - Susanne Sattler
- Imperial College London, London, United Kingdom
- Medical University Graz, Graz, Austria
| | - Alberto Pugliese
- Diabetes Research Institute, Miller School of Medicine, University of Miami, Miami, FL
| | - Laurie Landry
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Colleen Elso
- Immunology and Diabetes Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Maki Nakayama
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Stuart Mannering
- Immunology and Diabetes Unit, St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | - Nadia Rosenthal
- The Jackson Laboratory, Bar Harbor, ME
- Imperial College London, London, United Kingdom
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Carré A, Zhou Z, Perez-Hernandez J, Samassa F, Lekka C, Manganaro A, Oshima M, Liao H, Parker R, Nicastri A, Brandao B, Colli ML, Eizirik DL, Göransson M, Morales OB, Anderson A, Landry L, Kobaisi F, Scharfmann R, Marselli L, Marchetti P, You S, Nakayama M, Hadrup SR, Kent SC, Richardson SJ, Ternette N, Mallone R. Interferon-α promotes neo-antigen formation and preferential HLA-B-restricted antigen presentation in pancreatic β-cells. bioRxiv 2023:2023.09.15.557918. [PMID: 37745505 PMCID: PMC10516036 DOI: 10.1101/2023.09.15.557918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Interferon (IFN)-α is the earliest cytokine signature observed in individuals at risk for type 1 diabetes (T1D), but its effect on the repertoire of HLA Class I (HLA-I)-bound peptides presented by pancreatic β-cells is unknown. Using immunopeptidomics, we characterized the peptide/HLA-I presentation in in-vitro resting and IFN-α-exposed β-cells. IFN-α increased HLA-I expression and peptide presentation, including neo-sequences derived from alternative mRNA splicing, post-translational modifications - notably glutathionylation - and protein cis-splicing. This antigenic landscape relied on processing by both the constitutive and immune proteasome. The resting β-cell immunopeptidome was dominated by HLA-A-restricted ligands. However, IFN-α only marginally upregulated HLA-A and largely favored HLA-B, translating into a major increase in HLA-B-restricted peptides and into an increased activation of HLA-B-restricted vs. HLA-A-restricted CD8+ T-cells. A preferential HLA-B hyper-expression was also observed in the islets of T1D vs. non-diabetic donors, and we identified islet-infiltrating CD8+ T-cells from T1D donors reactive to HLA-B-restricted granule peptides. Thus, the inflammatory milieu of insulitis may skew the autoimmune response toward epitopes presented by HLA-B, hence recruiting a distinct T-cell repertoire that may be relevant to T1D pathogenesis.
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Affiliation(s)
- Alexia Carré
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | - Zhicheng Zhou
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | - Javier Perez-Hernandez
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
- Department of Nutrition and Health, Valencian International University (VIU), Valencia, Spain
| | | | - Christiana Lekka
- Islet Biology Group, Exeter Centre of Excellence in Diabetes Research, University of Exeter Medical School, Exeter, UK
| | - Anthony Manganaro
- Diabetes Center of Excellence, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Masaya Oshima
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | - Hanqing Liao
- Centre for Immuno-Oncology, Nuffield Department of Medicine, University of Oxford, UK
| | - Robert Parker
- Centre for Immuno-Oncology, Nuffield Department of Medicine, University of Oxford, UK
| | - Annalisa Nicastri
- Centre for Immuno-Oncology, Nuffield Department of Medicine, University of Oxford, UK
| | - Barbara Brandao
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | - Maikel L. Colli
- ULB Center for Diabetes Research, Université Libre de Bruxelles, Brussels, Belgium
| | - Decio L. Eizirik
- ULB Center for Diabetes Research, Université Libre de Bruxelles, Brussels, Belgium
| | - Marcus Göransson
- Department of Health Technology, Technical University of Denmark, Copenhagen, Denmark
| | | | - Amanda Anderson
- Barbara Davis Center for Diabetes, University of Colorado School of Medicine, Aurora, CO, USA
| | - Laurie Landry
- Barbara Davis Center for Diabetes, University of Colorado School of Medicine, Aurora, CO, USA
| | - Farah Kobaisi
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
| | | | - Lorella Marselli
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Piero Marchetti
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Sylvaine You
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
- Indiana Biosciences Research Institute, Indianapolis, IN, USA
| | - Maki Nakayama
- Barbara Davis Center for Diabetes, University of Colorado School of Medicine, Aurora, CO, USA
| | - Sine R. Hadrup
- Department of Health Technology, Technical University of Denmark, Copenhagen, Denmark
| | - Sally C. Kent
- Diabetes Center of Excellence, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Sarah J. Richardson
- Islet Biology Group, Exeter Centre of Excellence in Diabetes Research, University of Exeter Medical School, Exeter, UK
| | - Nicola Ternette
- Centre for Immuno-Oncology, Nuffield Department of Medicine, University of Oxford, UK
| | - Roberto Mallone
- Université Paris Cité, Institut Cochin, CNRS, INSERM, Paris, France
- Indiana Biosciences Research Institute, Indianapolis, IN, USA
- Assistance Publique Hôpitaux de Paris, Service de Diabétologie et Immunologie Clinique, Cochin Hospital, Paris, France
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Gaudreau P, Ajami N, Sepesi B, Karpinets T, Reuben A, Wong M, Parra E, Federico L, Gopalakrishnan V, Mitchell K, Negrao M, Spencer C, Vaporciyan A, Weissferdt A, Haymaker C, Tran H, Bernatchez C, Landry L, Roarty E, Cascone T, Heymach J, Zhang J, Wistuba I, Zhang J, Wargo J, Gibbons D. P1.04-11 Depicting the Intra-Tumoral Viral and Microbial Landscape of Localized NSCLC Using Standard Next Generation Sequencing Data. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Jin Y, Randall J, Elhalawani H, Elliott A, Anderson B, Landry L, Mohamed A, Fuller C, Chung C. Evaluation of Serial Diffusion Tensor Imaging to Reveal Subclinical Tumor Prior to Detection on Anatomical Imaging in Patients with Glioblastoma. Int J Radiat Oncol Biol Phys 2019. [DOI: 10.1016/j.ijrobp.2019.06.328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Burrack A, Nakayama M, Landry L, Coulombe M, Gill R. Autoimmunity as an endogenous source of heterologous alloimmunity (TRAN3P.868). The Journal of Immunology 2014. [DOI: 10.4049/jimmunol.192.supp.202.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Curiously, although autoimmunity is restricted to self MHC molecules, spontaneously diabetic NOD mice reject MHC-unrelated islet allografts more rapidly than syngeneic (NOD) grafts. We hypothesized that the autoimmune (islet-reactive) T cell repertoire harbors a subset of TCRs that also cross-react to allogeneic MHC molecules. To test this concept, we performed high throughput TCR sequencing of T cells infiltrating MHC-mismatched (C3H, H-2k) islet allografts on the day of rejection in diabetic female NOD mice. TCRs expressed in high frequency in the allograft (>1%) were cloned and tested for islet autoreactivity and/or alloreactivity following TCR cDNA transfection into IL-2 producing hybridoma cells. Of note, three TCRs studied that were the most frequent in the graft were also detected in the endogenous pancreas. All three transfectants expressing these TCRs were islet reactive. Importantly, all three of these TCR also were directly alloreactive to C3H spleen cells. Two of the three TCRs were MHC class I reactive (anti-H-2Dk), and the other was MHC class II-reactive (anti-I-Ak). These results suggest that dual auto/allo-reactive T cells are selectively expanded in islet allografts. As such, we propose that autoimmunity is an unusual source of endogenous heterologous alloreactivity that may accelerate allograft rejection by simultaneous auto- and allo-reactivity.
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Affiliation(s)
- Adam Burrack
- 1Immunology, University of Colorado Denver, Aurora, CO
| | - Maki Nakayama
- 2Pediatrics, University of Colorado Denver, Aurora, CO
| | - Laurie Landry
- 2Pediatrics, University of Colorado Denver, Aurora, CO
| | | | - Ronald Gill
- 3Surgery, University of Colorado Denver, Aurora, CO
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Abstract
Foodborne disease outbreaks associated with fresh fruits and vegetables have been increasing in occurrence worldwide. Canada has one of the highest per capita consumption rates of fresh fruits and vegetables in the world. In this article, we review the foodborne disease outbreaks linked to produce consumption in Canada from 2001 through 2009. The 27 produce-related outbreaks included an estimated 1,549 cases of illness. Bacterial infection outbreaks represented 66% of the total. Among these, Salmonella was the most frequent agent (50% of outbreaks) followed by Escherichia coli (33%) and Shigella (17%). Cyclospora cayetanensis was the only parasite detected and was associated with seven outbreaks. Among the foodborne viruses, only hepatitis A was implicated in two outbreaks. The food vehicles most commonly implicated in outbreaks were leafy greens and herbs (26% of outbreaks), followed by seed sprouts (11%). Contamination sources and issues related to the future control of fresh produce-related foodborne disease outbreaks also are discussed.
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Affiliation(s)
- G K Kozak
- Bureau of Microbial Hazards, Health Canada, Ottawa, Ontario, Canada K1A 0K9
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Landry L, Vincent WF, Bernatchez L. Parallel evolution of lake whitefish dwarf ecotypes in association with limnological features of their adaptive landscape. J Evol Biol 2007; 20:971-84. [PMID: 17465908 DOI: 10.1111/j.1420-9101.2007.01304.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Sympatric fish populations observed in many north temperate lakes are among the best models to study the processes of population divergence and adaptive radiation. Despite considerable research on such systems, little is known about the associations between ecological conditions and the extent of ecotypic divergence. In this study, we examined the biotic and abiotic properties of postglacial lakes in which lake whitefish, Coregonus clupeaformis, occur as a derived dwarf ecotype in sympatry with an ancestral normal ecotype. We compared 19 limnological variables between two groups of lakes known from previous studies to harbour sympatric dwarf and normal ecotypes with high and low levels of phenotypic and genetic differentiation respectively. We found clear environmental differences between the two lake groups. Namely, oxygen was the most discriminant variable, where lakes harbouring the most divergent populations were characterized by the greatest hypolimnetic oxygen depletion. These lakes also had lower zooplankton densities and a narrower distribution of zooplantonic prey length. These results suggest that the highest differentiation between sympatric ecotypes occurs in lakes with reduced habitat and prey availability that could increase competition for resources. This in turns supports the hypothesis that parallelism in the extent of phenotypic divergence among sympatric whitefish ecotypes is associated with parallelism in adaptive landscape in terms of differences in limnological characteristics, as well as availability and structure of the zooplanktonic community.
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Affiliation(s)
- L Landry
- Québec-Océan, Département de Biologie, Université Laval, QC, Canada.
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Currie A, Akwar H, MacDonald W, Saunders A, Baikie M, Sweet L, Landry L, Demczuk W, Panaro L. Home or away? Investigation of Salmonella enteritidis PFGE pattern SENXAI.0003 and SENBNI.0003, phage type 8, the in the Maritimes, 2005. Can Commun Dis Rep 2006; 32:231-9. [PMID: 17076033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Affiliation(s)
- A Currie
- Canadian Field Epidemiology Program, Public Health Agency of Canada, Ontario, Canada
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Abstract
AIM To determine the effect of a laxative alone and in combination with tegaserod in alleviating pain and improving stool frequency in adolescents with constipation predominant irritable bowel syndrome. PATIENTS Forty-eight postpubertal adolescents of both sexes with constipation predominant irritable bowel syndrome, as defined by Rome II criteria, were randomly allocated to Group A (n = 27) for treatment with a laxative (polyethylene glycol 3350 oral solution) only or Group B (n = 21) for combination therapy with the laxative and tegaserod. Symptoms of abdominal pain (scale 0-10) and frequency of bowel movements were recorded daily in the pre-treatment phase and the post-treatment phase after a 7-day 'washout' period. Patients served as their own controls. RESULTS Treatment with the laxative alone (Group A) resulted in significant increase in frequency of bowel movements (P < 0.05), but not significant improvement in pain (P > 0.05). Treatment with the combination of the laxative and tegaserod (Group B) led to significant increase in the frequency of bowel movements and also significant reduction in pain (P < 0.05). CONCLUSIONS The laxative alone improved stooling but not pain in adolescents with constipation predominant irritable bowel syndrome. Addition of tegaserod resulted in alleviation of pain as well.
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Affiliation(s)
- V Khoshoo
- West Jefferson Medical Center, New Orleans, LA 70072, USA.
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Abbas Z, Nolan L, Landry L, Galanis E, Egan C. Investigation of an outbreak of Legionnaires' disease in a hospital under construction: Ontario, September-October 2002. Can Commun Dis Rep 2003; 29:145-52. [PMID: 14526691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
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Loeb M, Simor AE, Landry L, McGeer A. Adherence to antibiotic guidelines for pneumonia in chronic-care facilities in Ontario. CLIN INVEST MED 2001; 24:304-10. [PMID: 11767234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVES To evaluate adherence to antibiotic recommendations for the treatment of pneumonia in patients who receive long-term care and to assess outcomes associated with these recommendations. DESIGN A prospective cohort study. SETTING Twenty-two facilities that provide long-term care in southern Ontario. PARTICIPANTS Older adults treated with antibiotics for a presumptive diagnosis of pneumonia and those with radiologically confirmed pneumonia METHODS Over a 12-month period, older patients who were treated with antibiotics for presumptive pneumonia were prospectively identified. A random sample of these antibiotic courses (646 courses in 638 patients) was reviewed using a standardized data collection form, and demographic and clinical data were collected. Antibiotic courses were classified according to Canadian and American Thoracic Society antibiotic recommendations for pneumonia. In patients with radiologically confirmed pneumonia, the effect of adherence to these recommendations on mortality and persistence of symptoms was assessed. RESULTS Only 27.6% (178 of 646) of antibiotic prescriptions evaluated met antibiotic recommendations for nursing-home-acquired pneumonia, and the proportion meeting these varied greatly by facility, ranging from 0% to 53% (median 31%). For patients with radiologically confirmed pneumonia, age (adjusted odds ratio [OR] 1.6, 95% confidence interval [CI] 1.0-2.4, per increase in 10 yr, p = 0.02), sex (adjusted OR 3.0, 95% CI 1.1-8.0, p = 0.03), and adherence to recommended antibiotics (OR 3.0, 95% CI 1.3-7.2, p = 0.01) were associated with death. Adherence to the recommended antibiotics was also associated with adverse reactions, which occurred in 10% of prescriptions meeting the recommendations (OR 2.4, 95% CI 1.3-4.6, p = 0.01). CONCLUSIONS Adherence to recommended guidelines for antibiotic treatment was low and highly variable among study facilities. Use of recommended antibiotic regimens was associated with increased adverse events and worse outcomes in patients with radiologically confirmed pneumonia.
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Affiliation(s)
- M Loeb
- Division of Medical Microbiology and Infectious Diseases, McMaster University and the Hamilton Regional Laboratory Program, Ont.
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Abstract
OBJECTIVE To determine the incidence and variability of antibiotic use in facilities which provide chronic care and to determine how often clinical criteria for infection are met when antibiotics are prescribed in these facilities. DESIGN A prospective, 12-month, observational cohort study. SETTING Twenty-two facilities which provide chronic care in southwestern Ontario. PARTICIPANTS Patients who were treated with systemic antibiotics over the study period. MEASUREMENTS Characteristics of antibiotic prescriptions (name, dose, duration, and indication) and clinical features of randomly selected patients who were treated with antibiotics. RESULTS A total of 9,373 courses of antibiotics were prescribed for 2,408 patients (66% of all patients in study facilities). The incidence of antibiotic prescriptions in the facilities ranged from 2.9 to 13.9 antibiotic courses per 1,000 patient-days. Thirty-six percent of antibiotics were prescribed for respiratory tract infections, 33% for urinary infections, and 13% for skin and soft tissue infections. Standardized surveillance definitions of infection were met in 49% of the 1,602 randomly selected patients who were prescribed antibiotics. Diagnostic criteria for respiratory, urinary, and skin infection were met in 58%, 28%, and 65% of prescriptions, respectively. One third of antibiotic prescriptions for a urinary indication were for asymptomatic bacteriuria. Adverse reactions were noted in 6% of prescriptions for respiratory and urinary infections and 4% of prescriptions for skin infection. CONCLUSIONS Antibiotic use is frequent and highly variable amongst patients who receive chronic care. Reducing antibiotic prescriptions for asymptomatic bacteriuria represents an important way to optimize antibiotic use in this population.
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Affiliation(s)
- M Loeb
- Division of Microbiology, Department of Pathology, McMaster University, Hamilton, Ontario, Canada.
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Iyer RS, Jacobs JP, Elliott MJ, de Leval MR, Stark J, Thul J, Wippermann F, Huth R, Michel-Behnke I, Schmid FX, Schranz D, Patel NR, Newth CJL, Duval ELIM, Kavelaars A, Veenhuizen L, van Vught AJ, van de Wal HJCM, Heijnen CJ, Michel-Behnke I, Schnittker C, Schmid FX, Wippermann CF, Thul J, Huth RG, Schranz D, Vázquez P, López-Herce J, Carrillo A, Sánchez M, Moral R, Bustinza A, Vassallo J, Cernadas C, Saporiti A, Landry L, Rivello G, Buamsha D, Rufach D, Magliola R, Alcaraz A, Sancho L, Manzano L, Esquivel F, Carrilo A, Alvarez-Mon M, Esquivel F, Sánchez-Galindo A. Cardiac surgery. Intensive Care Med 1996. [DOI: 10.1007/bf03216403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Jolivet J, Landry L, Pinard MF, McCormack JJ, Tong WP, Eisenhauer E. A phase I study of trimetrexate, an analog of methotrexate, administered monthly in the form of nine consecutive daily bolus injections. Cancer Chemother Pharmacol 1987; 20:169-72. [PMID: 2959389 DOI: 10.1007/bf00253973] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Trimetrexate glucuronate (TMTX) is a methotrexate (MTX) analog that is active against transport-deficient MTX-resistant tumor cells. We performed a phase I study of TMTX administered by daily bolus for 9 consecutive days since this schedule is one of the most active in experimental murine tumor models. The drug was administered in this fashion every 4 weeks for at least two cycles. Fifteen patients with refractory metastatic cancers were studied and all had received prior chemotherapy. The dose-limiting toxicity was a rapidly reversible thrombocytopenia first seen at a daily dose of 4.0 mg/m2 which occurred 7 days after the end of TMTX administration. There was great inter- and intrapatient variability in the platelet nadirs observed in the six patients treated at 4.0 mg/m2. One patient died of massive hemoptysis during a platelet nadir at that dose level. Granulocyte counts never dropped below 1500/mm3. Only one patient had significant non-hematological toxicity: a radiation recall skin toxicity along with a self-limited maculopapular rash. One patient with melanoma and lung metastases treated at 4.0 mg/m2 had a partial response. TMTX plasma levels were measured by HPLC every 3 days prior to daily dosing in patients receiving 4 mg/m2 to determine whether drug accumulation occurred during this prolonged administration schedule. Nadir drug levels varied from less than 0.02 to 0.35 microM and did not seem to increase during the 9-day schedule in individual patients. By comparison with other phase I trials, the hematologic toxicity of TMTX seems to be schedule-dependent, with less drug being tolerated and more severe thrombocytopenia observed with more protracted treatment protocols. A firm phase II starting dose for daily bolus X 9 schedules is difficult to recommend in view of the variable toxicity observed in the patients treated at 4.0 mg/m2 daily, who, in addition, had all been extensively pretreated. A reasonable starting dose might be 3.0 mg/m2 daily with built-in dosage increases or decreases.
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Affiliation(s)
- J Jolivet
- Hôpital Notre-Dame, Montreal, Quebec, Canada
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Ozario P, Landry L. [The number of physicians per inhabitant remains insufficient in developing countries--no noticeable change tor the last 10 years]. Infirm Fr 1981:6. [PMID: 6910472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Ozorio P, Landry L. [Number of physicians per inhabitant continues to be insufficient in developing nations (without notable changes in the last 10 years)]. Rev Sanid Hig Publica (Madr) 1981; 55:681-684. [PMID: 7348415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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