1
|
Domeshek LF, Zuo KJ, Letourneau S, Klar K, Anthony A, Ho ES, Hopyan S, Clarke HM, Davidge KM. Surgery for internal rotation contracture in infancy may obviate the need for brachial plexus nerve reconstruction: early experience. J Shoulder Elbow Surg 2024; 33:291-299. [PMID: 37479177 DOI: 10.1016/j.jse.2023.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/22/2023] [Accepted: 06/13/2023] [Indexed: 07/23/2023]
Abstract
BACKGROUND Shoulder internal rotation contracture and subluxation in the first year of life has long been recognized in some patients with brachial plexus birth injury (BPBI). Surgical management of shoulder pathology has traditionally been undertaken following nerve reconstruction as necessary. In some patients; however, shoulder pathology may impair or obscure functional neuromuscular recovery of the upper extremity. As a proof of concept, we report a highly selected subset of patients with BPBI in whom shoulder surgery undertaken before one year of age obviated the need for neuroma resection and nerve grafting. METHODS A retrospective review was performed of all patients with upper trunk BPBI who underwent shoulder surgery before one year of age from 2015 to 2018. Upper extremity motor function was evaluated with preoperative and postoperative Active Movement Scale scores, Cookie tests, and the requirement for subsequent neuroma resection and nerve grafting. RESULTS Fifteen patients with BPBI meeting the inclusion criteria underwent shoulder surgery (including a subscapularis slide and tendon transfers of the teres major and latissimus dorsi muscles) before 1 year of age. Preoperatively, no patients of the appropriate age passed the Cookie test for elbow flexion. Thirteen patients either passed the Cookie test or scored Active Movement Scale score 7 for elbow flexion at or before the last available follow-up undertaken at a median age of 3.4 [1.4, 5.2] years. One of those 13 patients underwent single fascicular distal nerve transfer to improve elbow flexion before subsequently passing the Cookie test. Two patients did not have sufficient follow-up to assess elbow flexion. CONCLUSION Although the exact role of shoulder surgery in infancy for BPBI remains to be defined, the findings from this study provide proof of concept that early, targeted surgical treatment of the shoulder may obviate the need for brachial plexus nerve reconstruction in a highly selected group of infants with BPBI.
Collapse
Affiliation(s)
- Leahthan F Domeshek
- Division of Plastic and Reconstructive Surgery, The Hospital for Sick Children and the Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Kevin J Zuo
- Division of Plastic and Reconstructive Surgery, The Hospital for Sick Children and the Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Sasha Letourneau
- Division of Plastic and Reconstructive Surgery, The Hospital for Sick Children and the Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Karen Klar
- Department of Rehabilitation, The Hospital for Sick Children, Toronto, ON, Canada
| | - Alison Anthony
- Department of Rehabilitation, The Hospital for Sick Children, Toronto, ON, Canada
| | - Emily S Ho
- Department of Rehabilitation, The Hospital for Sick Children, Toronto, ON, Canada
| | - Sevan Hopyan
- Division of Orthopedic Surgery, The Hospital for Sick Children and the Department of Surgery, University of Toronto, Toronto, ON, Canada
| | - Howard M Clarke
- Division of Plastic and Reconstructive Surgery, The Hospital for Sick Children and the Department of Surgery, University of Toronto, Toronto, ON, Canada.
| | - Kristen M Davidge
- Division of Plastic and Reconstructive Surgery, The Hospital for Sick Children and the Department of Surgery, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
2
|
Dong H, Shin H, Ho E, Jin HJ, Letourneau S, Banerjee T, Masschelein G, Davidson J, Wilson C, de Ribaupierre S, Eagleson R, Symonette CJ. Next-Generation Remote Hand Assessments: Cross-Platform DIGITS Web Application. Journal of Hand Surgery Global Online 2023. [DOI: 10.1016/j.jhsg.2023.01.016] [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: 02/27/2023] Open
|
3
|
Ring J, Heinelt M, Sharma S, Letourneau S, Jeschke MG. Oxandrolone in the Treatment of Burn Injuries: A Systematic Review and Meta-analysis. J Burn Care Res 2021; 41:190-199. [PMID: 31504621 DOI: 10.1093/jbcr/irz155] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Severe burns induce a profound hypermetabolic response, leading to a prolonged state of catabolism associated with organ dysfunction and delay of wound healing. Oxandrolone, a synthetic testosterone analog, may alleviate the hypermetabolic catabolic state thereby decreasing associated morbidity. However, current literature has reported mixed outcomes on complications following Oxandrolone use, specifically liver and lung function. We conducted an updated systematic review and meta-analysis studying the effects of Oxandrolone on mortality, length of hospital stay, progressive liver dysfunction, and nine secondary outcomes. We searched Pubmed, EMBASE, Web of Science, CINAHL, and Cochrane Databases of Systematic Reviews and Randomized Controlled Trials. Thirty-one randomized control trials and observational studies were included. Basic science and animal studies were excluded. Only studies comparing Oxandrolone to standard of care, or placebo, were included. Oxandrolone did not affect rates of mortality (relative risk [RR]: 0.72; 95% confidence interval [CI]: 0.47 to 1.08; P = .11) or progressive liver dysfunction (RR: 1.04; 95% CI: 0.59 to 1.85; P = .88), but did decrease length of stay in hospital. Oxandrolone significantly increased weight regain, bone mineral density, percent lean body mass, and decreased wound healing time for donor graft sites. Oxandrolone did not change the incidence of transient liver dysfunction or mechanical ventilation requirements. There is evidence to suggest that Oxandrolone is a beneficial adjunct to the acute care of burn patients; shortening hospital stays and improving several growth and wound healing parameters. It does not appear that Oxandrolone increases the risk of progressive or transient liver injury, although monitoring liver enzymes is recommended.
Collapse
Affiliation(s)
- Justine Ring
- School of Medicine, Queen's University, Kingston, Ontario, Canada.,Undergraduate Medical Education, Kingston, Ontario, Canada
| | - Martina Heinelt
- School of Medicine, Queen's University, Kingston, Ontario, Canada.,Undergraduate Medical Education, Kingston, Ontario, Canada
| | - Shubham Sharma
- School of Medicine, Queen's University, Kingston, Ontario, Canada.,Undergraduate Medical Education, Kingston, Ontario, Canada
| | - Sasha Letourneau
- School of Medicine, Queen's University, Kingston, Ontario, Canada.,Undergraduate Medical Education, Kingston, Ontario, Canada
| | - Marc G Jeschke
- Biological Sciences, Sunnybrook Research Institute, Toronto, Ontario, Canada.,Ross Tilley Burn Centre, Sunnybrook Hospital, Toronto, Ontario, Canada.,Department of Surgery, Division of Plastic Surgery and Department of Immunology, University of Toronto, Ontario, Canada
| |
Collapse
|
4
|
Letourneau S, Zewdie ET, Jadavji Z, Andersen J, Burkholder LM, Kirton A. Clinician awareness of brain computer interfaces: a Canadian national survey. J Neuroeng Rehabil 2020; 17:2. [PMID: 31907010 PMCID: PMC6945584 DOI: 10.1186/s12984-019-0624-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Accepted: 11/13/2019] [Indexed: 12/13/2022] Open
Abstract
Background Individuals with severe neurological disabilities but preserved cognition, including children, are often precluded from connecting with their environments. Brain computer interfaces (BCI) are a potential solution where advancing technologies create new clinical opportunities. We evaluated clinician awareness as a modifiable barrier to progress and identified eligible populations. Methods We executed a national, population-based, cross-sectional survey of physician specialists caring for persons with severe disability. An evidence- and experience-based survey had three themes: clinician BCI knowledge, eligible populations, and potential impact. A BCI knowledge index was created and scored. Canadian adult and pediatric neurologists, physiatrists and a subset of developmental pediatricians were contacted. Secure, web-based software administered the survey via email with online data collection. Results Of 922 valid emails (664 neurologists, 253 physiatrists), 137 (15%) responded. One third estimated that ≥10% of their patients had severe neurological disability with cognitive capacity. BCI knowledge scores were low with > 40% identifying as less than “vaguely aware” and only 15% as “somewhat familiar” or better. Knowledge did not differ across specialties. Only 6 physicians (4%) had patients using BCI. Communication and wheelchair control rated highest for potentially improving quality of life. Most (81%) felt BCI had high potential to improve quality of life. Estimates suggested that > 13,000 Canadians (36 M population) might benefit from BCI technologies. Conclusions Despite high potential and thousands of patients who might benefit, BCI awareness among clinicians caring for disabled persons is poor. Further, functional priorities for BCI applications may differ between medical professionals and potential BCI users, perhaps reflecting that clinicians possess a less accurate understanding of the desires and needs of potential end-users. Improving knowledge and engaging both clinicians and patients could facilitate BCI program development to improve patient outcomes.
Collapse
Affiliation(s)
- Sasha Letourneau
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, 2500 University Drive N.W., Calgary, AB, T2N 1N4, Canada
| | - Ephrem Takele Zewdie
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, 2500 University Drive N.W., Calgary, AB, T2N 1N4, Canada
| | - Zeanna Jadavji
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, 2500 University Drive N.W., Calgary, AB, T2N 1N4, Canada.,Clinical Neurosciences, Cumming School of Medicine, University of Calgary, 2500 University Drive N.W, Calgary, AB, AB T2N 1N4, Canada
| | - John Andersen
- Department of Pediatrics, University of Alberta, 116 St. and 85 Ave, Edmonton, AB T6G 2R3, Canada
| | - Lee M Burkholder
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, 2500 University Drive N.W., Calgary, AB, T2N 1N4, Canada.,Clinical Neurosciences, Cumming School of Medicine, University of Calgary, 2500 University Drive N.W, Calgary, AB, AB T2N 1N4, Canada
| | - Adam Kirton
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, 2500 University Drive N.W., Calgary, AB, T2N 1N4, Canada. .,Clinical Neurosciences, Cumming School of Medicine, University of Calgary, 2500 University Drive N.W, Calgary, AB, AB T2N 1N4, Canada. .,Department of Pediatrics, University of Alberta, 116 St. and 85 Ave, Edmonton, AB T6G 2R3, Canada. .,Alberta Children's Hospital Research Institute, 28 Oki Drive S.W, Calgary, AB, T3B6A8, Canada. .,Hotchkiss Brain Institute, University of Calgary, 2500 University Drive N.W, Calgary, AB, T2N 1N4, Canada.
| |
Collapse
|
5
|
Spradbrow J, Letourneau S, Grabell J, Liang Y, Riddel J, Hopman W, Blanchette VS, Rand ML, Coller BS, Paterson AD, James PD. Bleeding assessment tools to predict von Willebrand disease: Utility of individual bleeding symptoms. Res Pract Thromb Haemost 2020; 4:92-99. [PMID: 31989089 PMCID: PMC6971303 DOI: 10.1002/rth2.12256] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 08/19/2019] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Bleeding assessment is part of the diagnostic workup of von Willebrand disease (VWD). Bleeding assessment tools (BATs) have standardized obtaining this information but have been criticized because they are time consuming. OBJECTIVE To use our legacy data to determine which questions from BATs are the strongest predictors of a VWD diagnosis. PATIENTS/METHODS Bleeding score data from 3 different BATs were used. Patients aged <12 years were excluded. Questions on BATs relate to different bleeding symptoms, and each symptom is scored by severity. Scores for each symptom were sorted based on whether they indicated clinically significant bleeding, and nonsignificant scores were set as the reference category. Multivariable logistic regression was used to determine the symptoms that were the strongest predictors of a laboratory-confirmed VWD diagnosis. RESULTS A total of 927 participants were included; 144 (16%) were patients with VWD, and 783 (84%) were healthy controls. The top 3 symptoms for which a clinically significant positive response increased the likelihood of VWD were hemarthrosis (odds ratio [OR], 19.2; 95% confidence interval [CI], 3.7-100.4), postsurgical bleeding (OR, 15.2; 95% CI, 5.9-38.9), and menorrhagia (OR, 10.3; 95% CI, 4.9-21.9). With each increase in number of bleeding symptom categories with clinically significant scores, subjects had a stepwise increase in odds of a VWD diagnosis. CONCLUSIONS Our results suggest that most of the bleeding symptoms on BATs are significant predictors of VWD, and there is value in assessing multiple bleeding symptoms when eliciting a bleeding history. Certain bleeding symptoms are more useful predictors than others. Future BAT revisions may consider adding a relative weighting to each symptom.
Collapse
Affiliation(s)
| | | | - Julie Grabell
- Department of MedicineQueen's UniversityKingstonONCanada
| | - Yupu Liang
- Research BioinformaticsRockefeller UniversityNew YorkNYUSA
| | - James Riddel
- Division of Hematology/OncologyUniversity of CaliforniaSan FranciscoCAUSA
| | - Wilma Hopman
- Clinical Research CentreKingston General HospitalKingstonONCanada
| | - Victor S. Blanchette
- Department of PediatricsUniversity of TorontoTorontoONCanada
- Division of Haematology/OncologyThe Hospital for Sick ChildrenTorontoONCanada
| | - Margaret L. Rand
- Departments of Laboratory Medicine & Pathobiology, Biochemistry and PaediatricsUniversity of TorontoTorontoONCanada
- SickKids, Division of Haematology/Oncology and Translational Medicine, Research InstituteHospital for Sick ChildrenTorontoONCanada
| | - Barry S. Coller
- Allen and Frances Adler Laboratory of Blood and Vascular BiologyRockefeller UniversityNew YorkNYUSA
| | - Andrew D. Paterson
- Program in Genetics and Genome BiologyThe Hospital for Sick ChildrenTorontoONCanada
| | - Paula D. James
- Department of MedicineQueen's UniversityKingstonONCanada
| |
Collapse
|
6
|
Boyman O, Krieg C, Letourneau S, Webster K, Surh CD, Sprent J. Selectively expanding subsets of T cells in mice by injection of interleukin-2/antibody complexes: implications for transplantation tolerance. Transplant Proc 2012; 44:1032-4. [PMID: 22564618 DOI: 10.1016/j.transproceed.2012.01.093] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The biological activity of interleukin (IL)-2 and other cytokines in vivo can be augmented by binding to certain anti-cytokine monoclonal antibodies (mAb). Here, we review evidence on how IL-2/anti-IL-2 mAb complexes can be used to cause selective stimulation and expansion of certain T-cell subsets. With some anti-IL-2 mAbs, injection of IL-2/mAb complexes leads to expansion of CD8 T effector cells but not CD4 T regulatory cells (Tregs); these complexes exert less adverse side effects than soluble IL-2 and display powerful antitumor activity. Other IL-2/mAb complexes have minimal effects on CD8 T cells but cause marked expansion of Tregs. Preconditioning mice with these complexes leads to permanent acceptance of MHC-disparate pancreatic islets in the absence of immunosuppression.
Collapse
Affiliation(s)
- O Boyman
- Laboratory of Applied Immunobiology, University of Zurich, Zurich, Switzerland
| | | | | | | | | | | |
Collapse
|
7
|
Letourneau S, Jensen L. Impact of a decision tree on chronic wound care. J Wound Ostomy Continence Nurs 1998; 25:240-7. [PMID: 9923258] [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: 02/10/2023]
Abstract
OBJECTIVE To examine the use of a decision tree and its impact on the accuracy of decision making for chronic wound care. DESIGN Descriptive comparative design; replication study. SETTINGS AND SUBJECTS Data were collected from 2 groups of home care nurses in large urban centers. One group was measured after initial contact with the decision tree, and the other group was measured 2 years after implementation of the decision tree. INSTRUMENTS The chronic wound management decision tree (CWMDT) designed by Knight was used, in combination with pictorial case studies developed by Willey and Swords. METHODS Edmonton Home Care Program nurses, having used a decision tree for 2 years, completed 3 pictorial case studies without the aid of a written copy of the CWMDT. Current accuracy of wound care staging and treatment was compared with the Melchior-MacDougall and Lander results. After this procedure, Calgary Health Services home care nurses completed 3 pictorial case studies to assess the accuracy of wound care staging and treatment between 2 groups: with the CWMDT and without the CWMDT. A questionnaire was completed on factors identified to influence decision making in wound care. MAIN OUTCOME MEASURE Accuracy and confidence of decision making in wound care staging and treatment. RESULTS Accuracy of decision making with use of the CWMDT improved over time, as did accuracy of decision making after initial contact with the decision tree. Age, experience in nursing and home care, number of in-services attended, and number of chronic wounds treated, were not found to correlate with accuracy of decision making. CONCLUSION A decision tree can assist with decision making by guiding the nurse through assessment and treatment options.
Collapse
Affiliation(s)
- S Letourneau
- Capital Health Region, Alberta Health, Edmonton, Alberta, Canada
| | | |
Collapse
|
8
|
Hamilton SM, Letourneau S, Pekeles E, Voaklander D, Johnston DW. The impact of regionalization on a surgery program in the Canadian health care system. Arch Surg 1997; 132:605-9; discussion 609-11. [PMID: 9197852 DOI: 10.1001/archsurg.1997.01430300047010] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To examine the impact of the regionalization of health care on the provision of surgical services in the Capital Health Region (Edmonton) of the province of Alberta. DESIGN A 4-year retrospective descriptive analysis using data from the Canadian Institute for Health Information and from the Capital Health Region data banks. SETTING To control health care costs, the provincially funded health care system in Alberta reformed its governance structure and service provision model. We studied community hospitals and an academic health sciences center. PATIENTS All patients undergoing surgical care in the region. INTERVENTIONS Regionalization of the organizational structure with the elimination of hospital boards, consolidation of services on specific sites within the regional system, and a major reduction in funding. OUTCOME MEASURES Inpatient and day surgery procedure volumes, average length of hospital stay, relative value units, bed use, and mortality. RESULTS The Capital Health Region has a population of 723,000 people, with 5 acute care institutions. Eighteen clinical programs now provide care through 2 referral hospitals and 3 community health centers. The reduction in operating dollars for this region was $167.1 million from fiscal years 1992-1993 to 1996-1997. Redistribution of surgical services occurred on July 1, 1995, resulting in an 18% inpatient bed reduction. Regionally, the number of acute care beds has declined from 2.25 to 1.47 per 1000 population (P < .001). Bed use has fallen from 637 to 442 inpatient days per 1000 population (P < .001). The surgery volume (1995-1996) was 44770 procedures (-3.1%). Redistribution of surgical services into high- and low-acuity settings has resulted in most surgeons working on 2 sites. Overall average length of hospital stay has decreased significantly (P < .001); however, it has increased, together with the average relative value units, in the institutions caring for patients with high-acuity surgical illnesses. Mortality remains unchanged. CONCLUSIONS Regionalization and funding reductions within the surgical program in the Capital Health Region have resulted in a small reduction in surgical volumes. There have been major changes in service provision and the way surgeons practice.
Collapse
|
9
|
Daniels E, Letourneau S, Turbide C, Kuprina N, Rudinskaya T, Yazova AC, Holmes KV, Dveksler GS, Beauchemin N. Biliary glycoprotein 1 expression during embryogenesis: correlation with events of epithelial differentiation, mesenchymal-epithelial interactions, absorption, and myogenesis. Dev Dyn 1996; 206:272-90. [PMID: 8896983 DOI: 10.1002/(sici)1097-0177(199607)206:3<272::aid-aja5>3.0.co;2-f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Biliary glycoprotein (Bgp1), a carcinoembryonic antigen-related family member of the immunoglobulin superfamily, is involved in normal and neoplastic events. Analysis of Bgp1 expression throughout post-implantation mouse embryogenesis using reverse transcription-polymerase chain reactions, immunostaining with anti-Bgp1 monoclonal antibodies, and in situ hybridization with specific Bgp1 cDNA fragments revealed that Bgp1 may be involved in a number of specific embryonic processes. Immunoblot analysis of Bgp1 deletion mutant proteins indicated that distinguishable epitopes of the molecule were preferentially identified by the three Bgp1 antibodies used in this study. This distinction is supported by our immunolocalization studies during mouse embryogenesis in which the three antibodies revealed specific patterns of Bgp1 expression. Bgp1 is not expressed in early post-implantation embryos (7.5 dpc), but is found in the placenta and extra-embryonic tissues (decidual endothelial cells, giant trophoblasts, yolk sac visceral endoderm, and endometrial glands) at this time. The primitive gut epithelium and surface ectoderm were the first embryonic tissues to express Bgp1. Significant Bgp1 expression was also observed later during epithelial-mesenchymal interactions (skin, meninges, lung, kidney, salivary glands, pancreas). A unique epitope of Bgp1, detectable by the monoclonal antibody CC1, was also associated with mesenchymal expression and was prominent during myogenesis (secondary myotube formation) at sites of terminal differentiation. These studies suggest multiple roles for isoforms and glycoforms of the Bgp1 proteins localized in specific sites during prenatal development.
Collapse
Affiliation(s)
- E Daniels
- Department of Anatomy and Cell Biology, McGill University, Montreal, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Letourneau S, Greenbaum M, Cournoyer D. Retrovirus-mediated gene transfer of rat glutathione S-transferase Yc confers in vitro resistance to alkylating agents in human leukemia cells and in clonogenic mouse hematopoietic progenitor cells. Hum Gene Ther 1996; 7:831-40. [PMID: 8860835 DOI: 10.1089/hum.1996.7.7-831] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [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: 02/02/2023] Open
Abstract
Recently, we have reported that N2Yc, a Moloney-based retrovirus vector expressing the Yc isoform of rat glutathione S-transferase (GST-Yc), conferred resistance to alkylating agents in mouse NIH-3T3 fibroblasts. In this report, we address the feasibility of using rat GST-Yc somatic gene transfer to confer chemoprotection to the hematopoietic system. Human chronic myelogenous leukemia K-562 cells were efficiently transduced with the N2Yc retrovirus vector and showed a significant increase in the 50% inhibitory concentration of chlorambucil (3.2- to 3.3-fold), mechlorethamine (4.7- to 5.3-fold), and melphalan (2.1- to 2.2-fold). In addition, primary murine clonogenic hematopoietic progenitor cells transduced with the N2Yc vector were significantly more resistant to alkylating agents in vitro than cells transduced with the antisense N2revYc vector. The survival of Yc-transduced hematopoietic colonies at 400 nM mechlorethamine and 4 mu M chlorambucil was 39.4% and 42.6%, respectively, compared to 27.2% and 30.4% for N2revYc-transduced cells. Future experiments will determine the level of chemoprotection achievable in vivo, following transplantation of N2Yc-transduced hematopoietic cells in mice.
Collapse
Affiliation(s)
- S Letourneau
- Department of Medicine, Montreal General Hospital, Montreal, Canada
| | | | | |
Collapse
|