1
|
Cocce KJ, Jasper JS, Desautels TK, Everett L, Wardell S, Westerling T, Baldi R, Wright TM, Tavares K, Yllanes A, Bae Y, Blitzer JT, Logsdon C, Rakiec DP, Ruddy DA, Jiang T, Broadwater G, Hyslop T, Hall A, Laine M, Phung L, Greene GL, Martin LA, Pancholi S, Dowsett M, Detre S, Marks JR, Crawford GE, Brown M, Norris JD, Chang CY, McDonnell DP. The Lineage Determining Factor GRHL2 Collaborates with FOXA1 to Establish a Targetable Pathway in Endocrine Therapy-Resistant Breast Cancer. Cell Rep 2019; 29:889-903.e10. [PMID: 31644911 PMCID: PMC6874102 DOI: 10.1016/j.celrep.2019.09.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 07/02/2019] [Accepted: 09/12/2019] [Indexed: 12/25/2022] Open
Abstract
Notwithstanding the positive clinical impact of endocrine therapies in estrogen receptor-alpha (ERα)-positive breast cancer, de novo and acquired resistance limits the therapeutic lifespan of existing drugs. Taking the position that resistance is nearly inevitable, we undertook a study to identify and exploit targetable vulnerabilities that were manifest in endocrine therapy-resistant disease. Using cellular and mouse models of endocrine therapy-sensitive and endocrine therapy-resistant breast cancer, together with contemporary discovery platforms, we identified a targetable pathway that is composed of the transcription factors FOXA1 and GRHL2, a coregulated target gene, the membrane receptor LYPD3, and the LYPD3 ligand, AGR2. Inhibition of the activity of this pathway using blocking antibodies directed against LYPD3 or AGR2 inhibits the growth of endocrine therapy-resistant tumors in mice, providing the rationale for near-term clinical development of humanized antibodies directed against these proteins.
Collapse
Affiliation(s)
- Kimberly J Cocce
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jeff S Jasper
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Taylor K Desautels
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Logan Everett
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Suzanne Wardell
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Thomas Westerling
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Robert Baldi
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Tricia M Wright
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Kendall Tavares
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Alex Yllanes
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Yeeun Bae
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | | | - Craig Logsdon
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Daniel P Rakiec
- Novartis Institutes for Biomedical Research, Oncology Disease Area, Cambridge, MA 02139, USA
| | - David A Ruddy
- Novartis Institutes for Biomedical Research, Oncology Disease Area, Cambridge, MA 02139, USA
| | - Tiancong Jiang
- Department of Biostatistics, Duke Cancer Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Gloria Broadwater
- Department of Biostatistics, Duke Cancer Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Terry Hyslop
- Department of Biostatistics, Duke Cancer Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Allison Hall
- Department of Pathology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Muriel Laine
- The Ben May Department for Cancer Research, The University of Chicago, Chicago, IL 60637, USA
| | - Linda Phung
- The Ben May Department for Cancer Research, The University of Chicago, Chicago, IL 60637, USA
| | - Geoffrey L Greene
- The Ben May Department for Cancer Research, The University of Chicago, Chicago, IL 60637, USA
| | - Lesley-Ann Martin
- Breast Cancer Now, Toby Robins Research Centre, Institute of Cancer Research, London, SW3 6JB, UK
| | - Sunil Pancholi
- Breast Cancer Now, Toby Robins Research Centre, Institute of Cancer Research, London, SW3 6JB, UK
| | - Mitch Dowsett
- Ralph Lauren Centre for Breast Cancer Research, Royal Marsden Hospital NHS Trust, London, SW3 6JJ, UK
| | - Simone Detre
- Ralph Lauren Centre for Breast Cancer Research, Royal Marsden Hospital NHS Trust, London, SW3 6JJ, UK
| | - Jeffrey R Marks
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Gregory E Crawford
- Department of Pediatrics, Duke University School of Medicine, Durham, NC 27710, USA
| | - Myles Brown
- Center for Functional Cancer Epigenetics, Dana-Farber Cancer Institute, Boston, MA 02215, USA; Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - John D Norris
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Ching-Yi Chang
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Donald P McDonnell
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA.
| |
Collapse
|
2
|
Holyoak DT, Chlebek C, Kim MJ, Wright TM, Otero M, van der Meulen MCH. Low-level cyclic tibial compression attenuates early osteoarthritis progression after joint injury in mice. Osteoarthritis Cartilage 2019; 27:1526-1536. [PMID: 31265883 PMCID: PMC6814162 DOI: 10.1016/j.joca.2019.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 06/02/2019] [Accepted: 06/06/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Mechanical loading and joint health have a unique relationship in osteoarthritis (OA) onset and progression. Although high load levels adversely affect cartilage health, exercise that involves low to moderate load levels can alleviate OA symptoms. We sought to isolate the beneficial effects of mechanical loading using controlled in vivo cyclic tibial compression. We hypothesized that low-level cyclic compression would attenuate post-traumatic OA symptoms induced by destabilization of the medial meniscus (DMM). METHODS 10-week-old C57Bl/6J male mice underwent DMM surgery (n = 51). After a 5-day post-operative recovery period, we applied daily cyclic tibial compression to the operated limbs at low (1.0N or 2.0N) or moderate (4.5N) magnitudes for 2 or 6 weeks. At the completion of loading, we compared cartilage and peri-articular bone features of mice that underwent DMM and loading to mice that only underwent DMM. RESULTS Compared to DMM alone, low-level cyclic compression for 6 weeks attenuated DMM-induced cartilage degradation (OARSI score, P = 0.008, 95% confidence interval (CI): 0.093 to 0.949). Low-level loading attenuated DMM-induced osteophyte formation after 2 weeks (osteophyte size, P = 0.033, 95% CI: 3.27-114.45 μm), and moderate loading attenuated subchondral bone sclerosis after 6 weeks (tissue mineral density (TMD), P = 0.011, 95% CI: 6.32-70.60 mg HA/ccm) compared to limbs that only underwent DMM. Finally, loading had subtle beneficial effects on cartilage cellularity and aggrecanase activity after DMM. CONCLUSION Low-level cyclic compression is beneficial to joint health after an injury. Therefore, the progression of early OA may be attenuated by applying well controlled, low-level loading shortly following joint trauma.
Collapse
Affiliation(s)
| | - C Chlebek
- Cornell University, Ithaca, NY, USA.
| | - M J Kim
- Cornell University, Ithaca, NY, USA.
| | - T M Wright
- Cornell University, Ithaca, NY, USA; Hospital for Special Surgery, New York, NY, USA; Weill Cornell Medicine, New York, NY, USA.
| | - M Otero
- Hospital for Special Surgery, New York, NY, USA.
| | - M C H van der Meulen
- Cornell University, Ithaca, NY, USA; Hospital for Special Surgery, New York, NY, USA.
| |
Collapse
|
3
|
Abstract
AIMS The aim of this study was to evaluate fretting and corrosion in retrieved oxidized zirconium (OxZr; OXINIUM, Smith & Nephew, Memphis, Tennessee) femoral heads and compare the results with those from a matched cohort of cobalt-chromium (CoCr) femoral heads. PATIENTS AND METHODS A total of 28 OxZr femoral heads were retrieved during revision total hip arthroplasty (THA) and matched to 28 retrieved CoCr heads according to patient demographics. The mean age at index was 56 years (46 to 83) in the OxZr group and 70 years (46 to 92) in the CoCr group. Fretting and corrosion scores of the female taper of the heads were measured according to the modified Goldberg scoring method. RESULTS The OxZr-retrieved femoral heads showed significantly lower mean corrosion scores than the CoCr heads (1.3 (1 to 2.75) vs 2.1 (1 to 4); p < 0.01). Mean fretting scores were also significantly lower in the OxZr cohort when compared with the CoCr cohort (1.3 (1 to 2) vs 1.5 (1 to 2.25); p = 0.02). OxZr heads had more damage in the proximal region compared with the distal region of the head. Location had no impact on damage of CoCr heads. A trend towards increased corrosion in large heads was seen only in the CoCr heads, although this was not statistically significant. CONCLUSION Retrieval analysis of OxZr femoral heads showed a decreased amount of fretting and corrosion compared with CoCr femoral heads. OxZr seems to be effective at reducing taper damage. Cite this article: Bone Joint J 2019;101-B:386-389.
Collapse
Affiliation(s)
- C Hampton
- Hospital for Special Surgery, New York, New York, USA
| | - L Weitzler
- Department of Biomechanics, Hospital for Special Surgery, New York, New York, USA
| | - E Baral
- Department of Biomechanics, Hospital for Special Surgery, New York, New York, USA
| | - T M Wright
- Department of Biomechanics, Hospital for Special Surgery, New York, New York, USA
| | - M P G Bostrom
- Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, New York, USA
| |
Collapse
|
4
|
Anderson FL, Koch CN, Elpers ME, Wright TM, Haas SB, Heyse TJ. Oxidised zirconium versus cobalt alloy bearing surfaces in total knee arthroplasty: 3D laser scanning of retrieved polyethylene inserts. Bone Joint J 2017; 99-B:793-798. [PMID: 28566399 DOI: 10.1302/0301-620x.99b6.bjj-2016-1281.r1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 02/22/2017] [Indexed: 11/05/2022]
Abstract
AIMS We sought to establish whether an oxidised zirconium (OxZr) femoral component causes less loss of polyethylene volume than a cobalt alloy (CoCr) femoral component in total knee arthroplasty. MATERIALS AND METHODS A total of 20 retrieved tibial inserts that had articulated with OxZr components were matched with 20 inserts from CoCr articulations for patient age, body mass index, length of implantation, and revision diagnosis. Changes in dimensions of the articular surfaces were compared with those of pristine inserts using laser scanning. The differences in volume between the retrieved and pristine surfaces of the two groups were calculated and compared. RESULTS The loss of polyethylene volume was 122 mm3 (standard deviation (sd) 87) in the OxZr group and 170 mm3 (sd 96) in the CoCr group (p = 0.033). The volume loss in the OxZr group was also lower in the medial (72 mm3 (sd 67) versus 92 mm3 (sd 60); p = 0.096) and lateral (49 mm3 (sd 36) versus 79 mm3 (sd 61); p = 0.096) compartments separately, but these differences were not significant. CONCLUSION Our results corroborate earlier findings from in vitro testing and visual retrieval analysis which suggest that polyethylene volume loss is lower with OxZr femoral components. Since both OxZr and CoCr are hard surfaces that would be expected to create comparable amounts of polyethylene creep, the differences in volume loss may reflect differences in the in vivo wear of these inserts. Cite this article: Bone Joint J 2017;99-B:793-8.
Collapse
Affiliation(s)
- F L Anderson
- Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA
| | - C N Koch
- Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA
| | - M E Elpers
- Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA
| | - T M Wright
- Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA
| | - S B Haas
- Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA
| | - T J Heyse
- University Hospital Marburg, Baldingerstraße, 35043 Marburg, Germany
| |
Collapse
|
5
|
Rasmussen NR, Debebe Z, Wright TM, Brooks SA, Sendor AB, Brannon A.R, Hakimi A.A, Hsieh JJ, Choueiri TK, Tamboli P, Maranchie JK, Hinds P, Wallen EM, Simpson C, Norris JL, Janzen WP, Rathmell WK. Expression of Ror2 mediates invasive phenotypes in renal cell carcinoma. PLoS One 2014; 9:e116101. [PMID: 25542006 PMCID: PMC4277431 DOI: 10.1371/journal.pone.0116101] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 12/04/2014] [Indexed: 11/18/2022] Open
Abstract
Ror2 is a Wnt ligand receptor that is overexpressed in a variety of tumors including clear cell renal cell carcinoma (ccRCC). Here we demonstrate that expression of wild type Ror2 results in increased tumorigenic properties in in vitro cell culture and in vivo xenograft models. In addition, Ror2 expression produced positive changes in both cell migration and invasion, which were dependent on matrix metalloprotease 2 (MMP2) activity. Mutations in key regions of the kinase domain of Ror2 resulted in the abrogation of increased tumor growth, cell migration, and cell invasion observed with expression of wild-type Ror2. Finally, we examined Ror2 expression as a prognostic biomarker for ccRCC utilizing the TCGA ccRCC dataset. High expression of Ror2 showed a significant correlation with higher clinical stage, nuclear grade, and tumor stage. Furthermore, high expression of Ror2 in ccRCC patients correlated with significant lower overall survival, cancer specific survival, and recurrence free survival. Together, these findings suggest that Ror2 plays a central role in influencing the ccRCC phenotype, and can be considered as a negative prognostic biomarker and potential therapeutic target in this cancer.
Collapse
Affiliation(s)
- Neal R. Rasmussen
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - Zufan Debebe
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - Tricia M. Wright
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - Samira A. Brooks
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
- Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - Adam B. Sendor
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - A . Rose Brannon
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, United States of America
| | - A . Ari Hakimi
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, United States of America
- Department of Surgery, Urology Service, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, United States of America
| | - James J. Hsieh
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, United States of America
- Department of Surgery, Urology Service, Memorial Sloan Kettering Cancer Center, New York, New York, 10065, United States of America
| | - Toni K. Choueiri
- Department of Medical Oncology and Kidney Cancer Center, Dana Farber Cancer Institute, Boston, Massachusetts, 02215, United States of America
| | - Pheroze Tamboli
- Department of Pathology, MD Anderson Cancer Center, Houston, Texas, 77030, United States of America
| | - Jodi K. Maranchie
- Department of Urologic Oncology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, 15219, United States of America
| | - Peter Hinds
- Department of Urologic Oncology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, 15219, United States of America
| | - Eric M. Wallen
- Department of Urology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - Catherine Simpson
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - Jacqueline L. Norris
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - William P. Janzen
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
| | - W. Kimryn Rathmell
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
- Departments of Medicine and Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, United States of America
- * E-mail:
| |
Collapse
|
6
|
Wright TM, Wardell SE, Jasper JS, Stice JP, Safi R, Nelson ER, McDonnell DP. Delineation of a FOXA1/ERα/AGR2 regulatory loop that is dysregulated in endocrine therapy-resistant breast cancer. Mol Cancer Res 2014; 12:1829-39. [PMID: 25100862 DOI: 10.1158/1541-7786.mcr-14-0195] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
UNLABELLED Tamoxifen, a selective estrogen receptor (ER) modulator (SERM), remains a frontline clinical therapy for patients with ERα-positive breast cancer. However, the relatively rapid development of resistance to this drug in the metastatic setting remains an impediment to a durable response. Although drug resistance likely arises by many different mechanisms, the consensus is that most of the implicated pathways facilitate the outgrowth of a subpopulation of cancer cells that can either recognize tamoxifen as an agonist or bypass the regulatory control of ERα. Notable in this regard is the observation here and in other studies that expression of anterior gradient homology 2 (AGR2), a known proto-oncogene and disulfide isomerase, was induced by both estrogen (17β-estradiol, E2) and 4-hydroxytamoxifen (4OHT) in breast cancer cells. The importance of AGR2 expression is highlighted here by the observation that (i) its knockdown inhibited the growth of both tamoxifen-sensitive and -resistant breast cancer cells and (ii) its increased expression enhanced the growth of ERα-positive tumors in vivo and increased the migratory capacity of breast cancer cells in vitro. Interestingly, as with most ERα target genes, the expression of AGR2 in all breast cancer cells examined requires the transcription factor FOXA1. However, in tamoxifen-resistant cells, the expression of AGR2 occurs in a constitutive manner, requiring FOXA1, but loses its dependence on ER. Taken together, these data define the importance of AGR2 in breast cancer cell growth and highlight a mechanism where changes in FOXA1 activity obviate the need for ER in the regulation of this gene. IMPLICATIONS These findings reveal the transcriptional interplay between FOXA1 and ERα in controlling AGR2 during the transition from therapy-sensitive to -resistant breast cancer and implicate AGR2 as a relevant therapeutic target.
Collapse
Affiliation(s)
- Tricia M Wright
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
| | - Suzanne E Wardell
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
| | - Jeff S Jasper
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
| | - James P Stice
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
| | - Rachid Safi
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
| | - Erik R Nelson
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
| | - Donald P McDonnell
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina.
| |
Collapse
|
7
|
Wright TM, Wardell SE, Nelson ER, McDonnell DP. Abstract A96: The role of the proto-oncogene AGR2 in endocrine resistant breast cancer. Mol Cancer Ther 2013. [DOI: 10.1158/1535-7163.targ-13-a96] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Tamoxifen, a selective estrogen receptor modulator (SERM), is used as a first line treatment for estrogen receptor (ER) positive breast cancer. Though most ER-positive breast cancers initially respond to tamoxifen, the development of resistance impedes durable responses to this intervention. Further, predicting which tumors are most likely to develop resistance remains a challenge. In part, this is due to the complexity of the mechanisms underlying resistance and the difficulty in translating insights from studies of tamoxifen pharmacology in vitro to the clinical setting. However, the results of most studies support the idea that resistance represents a change that enables cells to recognize tamoxifen as an agonist instead of an antagonist. Thus, identifying biomarkers downstream of the ER pathway that read on the relative agonist/antagonist activity of tamoxifen would likely improve the clinical utility of tamoxifen and other endocrine therapies in breast cancer.
Recent work by our lab and other groups has identified AGR2 as an ER target gene whose expression is induced by both 17β-estradiol (E2) and 4-hydroxytamoxifen (4OHT). AGR2 is a proto-oncogene whose elevated expression is associated with increased cell proliferation, migration and invasion in breast cancer. Additionally, in the clinical setting, AGR2 has been identified as playing an important role in tamoxifen resistance. In a cell line established within our lab from a human xenograft model of tamoxifen resistance (TamR), AGR2 is significantly overexpressed compared to the parental MCF7 cell line. Knockdown of AGR2 expression in the TamR cell line resulted in a dramatic inhibition of E2 induced cell growth and migratory potential, attesting to its importance in the pathobiology of advanced cancers. When overexpressed in the MCF7 cell line, AGR2 was secreted and induced migratory potential in the MCF7 and TamR breast cancer cell lines in vitro. Additionally, overexpressed AGR2 significantly increased tumor growth in vivo. In both the MCF7 and TamR cellular models of breast cancer, AGR2 expression is required for ER expression. However, in the TamR cell line, AGR2 expression is no longer controlled by ER, suggesting that under selective pressure, the TamR cell line has acquired an alternative mechanism to upregulate AGR2 expression. Additional work is currently underway to further understand the mechanism of AGR2 regulation as breast cancers progress to a tamoxifen resistant state.
This work is supported by a DOD Breast Cancer Postdoctoral Fellowship BC103843 (TMW) and a National Institutes of Health Grant R37 DK048807 (DPM).
Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A96.
Citation Format: Tricia M. Wright, Suzanne E. Wardell, Erik R. Nelson, Donald P. McDonnell. The role of the proto-oncogene AGR2 in endocrine resistant breast cancer. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A96.
Collapse
|
8
|
Rasmussen NR, Wright TM, Brooks SA, Hacker KE, Debebe Z, Sendor AB, Walker MP, Major MB, Green J, Wahl GM, Rathmell WK. Receptor tyrosine kinase-like orphan receptor 2 (Ror2) expression creates a poised state of Wnt signaling in renal cancer. J Biol Chem 2013; 288:26301-26310. [PMID: 23893409 DOI: 10.1074/jbc.m113.466086] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Expression of the receptor tyrosine kinase-like orphan receptor 2 (Ror2) has been identified in an increasing array of tumor types and is known to play a role as an important mediator of Wnt signaling cascades. In this study, we aimed to clarify Ror2 interactions with the Wnt pathways within the context of renal cell carcinoma (RCC). An examination of Ror2 expression in primary human RCC tumors showed a significant correlation with several Wnt signaling genes, including the classical feedback target gene Axin2. We provide evidence that Ror2 expression results in a partially activated state for canonical Wnt signaling through an increased signaling pool of β-catenin, leading to an enhancement of downstream target genes following Wnt3a stimulation in both renal and renal carcinoma-derived cells. Additionally, inhibition of low-density lipoprotein receptor-related protein 6 (LRP6) with either siRNA or dickkopf decreased the response to Wnt3a stimulation, but no change was seen in the increased β-catenin pool associated with Ror2 expression, suggesting that LRP6 cofactor recruitment is necessary for a Wnt3a-induced signal but that it does not participate in the Ror2 effect on β-catenin signaling. These results highlight a new role for Ror2 in conveying a tonic signal to stabilize soluble β-catenin and create a poised state of enhanced responsiveness to Wnt3a exogenous signals in RCC.
Collapse
Affiliation(s)
- Neal R Rasmussen
- From the Curriculum in Genetics and Molecular Biology,; Lineberger Comprehensive Cancer Center
| | - Tricia M Wright
- From the Curriculum in Genetics and Molecular Biology,; Lineberger Comprehensive Cancer Center
| | - Samira A Brooks
- Lineberger Comprehensive Cancer Center,; Curriculum in Toxicology
| | - Kathryn E Hacker
- From the Curriculum in Genetics and Molecular Biology,; Lineberger Comprehensive Cancer Center
| | | | | | | | - Michael Ben Major
- Lineberger Comprehensive Cancer Center,; Department of Cell Biology and Physiology, and
| | - Jennifer Green
- the Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037
| | - Geoffrey M Wahl
- the Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037
| | - W Kimryn Rathmell
- Lineberger Comprehensive Cancer Center,; Departments of Medicine and Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, and.
| |
Collapse
|
9
|
Nam D, Kepler CK, Neviaser AS, Jones KJ, Wright TM, Craig EV, Warren RF. Reverse total shoulder arthroplasty: current concepts, results, and component wear analysis. J Bone Joint Surg Am 2010; 92 Suppl 2:23-35. [PMID: 21189245 DOI: 10.2106/jbjs.j.00769] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- D Nam
- Sports Medicine and Shoulder Service, Department of Orthopaedic Surgery, Hospital for Special Surgery, New York, NY 10021, USA.
| | | | | | | | | | | | | |
Collapse
|
10
|
Wright TM, Rathmell WK. Identification of Ror2 as a hypoxia-inducible factor target in von Hippel-Lindau-associated renal cell carcinoma. J Biol Chem 2010; 285:12916-24. [PMID: 20185829 DOI: 10.1074/jbc.m109.073924] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ror2 is an orphan receptor tyrosine kinase with expression normally restricted to early stages of development. However, emerging evidence has placed aberrantly expressed Ror2, leading to an invasive phenotype, in several cancers including renal cell carcinoma (RCC). Although Ror2 is currently identified as up-regulated in an assortment of cancers, neither the regulatory role or mechanism of action have been delineated. We sought to place Ror2 in the most commonly mutated pathway of RCC, the loss of the tumor suppressor von Hippel-Lindau (VHL), which causes hypoxia-inducible factor (HIF)-1alpha and -2alpha stabilization and the transcriptional activation of a broad repertoire of response genes. We found that Ror2 was indeed associated with the pVHL loss in RCC as well as with VHL somatic mutations tightly coordinated with the induction of RCC. Additionally, knockdown and rescue analysis of HIF expression suggests that Ror2 is dependent on pathologic stabilization of either HIF-1alpha or HIF-2alpha. Subsequent evaluation of the ROR2 promoter suggests that HIF-2alpha and its dimerization partner, aryl hydrocarbon nuclear transferase localize to the ROR2 promoter via a cryptic transcriptional element. This data substantiates a unique regulation pattern for Ror2 in the VHL-HIF axis that has the potential to be applied to other cancer etiologies.
Collapse
Affiliation(s)
- Tricia M Wright
- Department of Genetics, Curriculum in Genetics and Molecular Biology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599, USA
| | | |
Collapse
|
11
|
Wright TM, Brannon AR, Gordan JD, Mikels AJ, Mitchell C, Chen S, Espinosa I, van de Rijn M, Pruthi R, Wallen E, Edwards L, Nusse R, Rathmell WK. Ror2, a developmentally regulated kinase, promotes tumor growth potential in renal cell carcinoma. Oncogene 2009; 28:2513-23. [PMID: 19448672 PMCID: PMC2771692 DOI: 10.1038/onc.2009.116] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Inappropriate kinase expression and subsequent promiscuous activity defines the transformation of many solid tumors including renal cell carcinoma (RCC). Thus, the expression of novel tumor-associated kinases has the potential to dramatically shape tumor cell behavior. Further, identifying tumor-associated kinases can lend insight into patterns of tumor growth and characteristics. Here, we report the identification of the RTK-like orphan receptor 2 (Ror2), a new tumor-associated kinase in RCC cell lines and primary tumors. Ror2 is an orphan receptor tyrosine kinase with physiological expression normally seen in the embryonic kidney. However, in RCC, Ror2 expression correlated with expression of genes involved at the extracellular matrix, including Twist and matrix metalloprotease-2 (MMP2). Expression of MMP2 in RCC cells was suppressed by Ror2 knockdown, placing Ror2 as a mediator of MMP2 regulation in RCC and a potential regulator of extracellular matrix remodeling. The suppression of Ror2 not only inhibited cell migration, but also inhibited anchorage-independent growth in soft agar and growth in an orthotopic xenograft model. These findings suggest a novel pathway of tumor-promoting activity by Ror2 within a subset of renal carcinomas, with significant implications for unraveling the tumorigenesis of RCC.
Collapse
Affiliation(s)
- T M Wright
- Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7295, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Baros AM, Wright TM, Latham PK, Miller PM, Anton RF. Alcohol consumption, %CDT, GGT and blood pressure change during alcohol treatment. Alcohol Alcohol 2007; 43:192-7. [PMID: 18039674 DOI: 10.1093/alcalc/agm156] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS Blood pressure (BP) changes in alcohol-dependent individuals during a 12-week alcohol relapse prevention study were examined in light of drinking status and biomarkers of alcohol consumption [carbohydrate-deficient transferrin (%CDT) and gamma-glutamyl transpeptidase (GGT)]. METHODS Of 160 randomized alcoholic individuals, 120 who had hypertension and in whom daily drinking data was available, at 6 and 12 weeks of treatment were included. The impact of alcohol consumption on change in systolic BP (SBP) and diastolic BP (DBP) was examined. Further analysis determined the relationship between BP and alcohol-use biomarkers. RESULTS A significant effect of complete abstinence on both SBP (-10 mmHg; P = 0.003) and DBP (-7 mmHg; P = 0.001) when compared to any drinking (SBP and DBP = -1 mmHg) was observed. At week 12, participants with a positive %CDT (> or =2.6) had 7 mmHg greater SBP (P = 0.01) and DBP (P < 0.001) than those with negative %CDT. Participants with positive GGT (> or =50 IU) had 10 mmHg greater SBP (P = 0.12) and 9 mmHg greater DBP (P = 0.03) than those with negative GGT. The percent change in SBP was correlated with percent change in %CDT (P = 0.003) but not GGT (P = ns). The percent change in DBP was correlated with both percent change in %CDT (P < 0.0001) and GGT (P = 0.03). CONCLUSIONS Abstinence from alcohol significantly decreased the BP and a positive relationship between BP and both alcohol-use biomarkers was illustrated. Since %CDT is more specific than GGT for heavy alcohol consumption, clinicians may monitor the role of alcohol in hypertension using %CDT as a supplemental aid, providing an objective assessment of drinking to influence BP treatment decisions.
Collapse
Affiliation(s)
- A M Baros
- Charleston Alcohol Research Center, Medical University of South Carolina, 67 President Street, PO Box 250861, Charleston, SC 29425, USA.
| | | | | | | | | |
Collapse
|
13
|
Abstract
BACKGROUND Alcohol abuse, especially when experienced in multiple cycles of chronic abuse and withdrawal, leads to a sensitization of central nervous system hyperexcitability that may culminate in overt expression of seizures. In spite of the growing prevalence of alcohol abuse and dependence in females shown in recent epidemiologic studies, evidence of sexual dimorphism in the expression of alcohol withdrawal-induced seizures and the development of seizure sensitization following multiple cycles of ethanol (EtOH) exposure and withdrawal has not been examined in either animal models or in clinical reports. METHODS Subjects in these experiments were male and female C3H/Hecr mice. The female mice were intact or ovariectomized, with ovariectomized mice receiving 17-beta-estradiol or placebo pellets. All mice were exposed to 4 cycles of exposure to 16-hour EtOH vapor, separated by 8-hour withdrawal periods. During each 8-hour withdrawal, hourly assessment of seizure propensity was assessed as handling-induced convulsions. Additional assessments were taken up to 72 hours after the final EtOH withdrawal cycle. RESULTS Male and female mice showed similar seizure propensity during an initial withdrawal from chronic EtOH. Across subsequent withdrawal cycles, however, male mice exhibited a robust increase in seizure severity beginning with the third withdrawal cycle. In marked contrast, female mice failed to demonstrate sensitization of seizure severity. The lack of seizure sensitization following up to 4 cycles of alcohol exposure and withdrawal could not be explained by hormonal status (presence or absence of estrogen) or by sex differences in blood alcohol levels. CONCLUSIONS Male and female mice exposed to the same number of cycles of EtOH withdrawal demonstrate differences in expression of seizures. Males show the typical sensitization of seizures, or kindling response, which has been reported clinically as well as in animal models, but females do not. The reason for the lack of seizure sensitization in female mice remains to be elucidated, but may be related to sex differences in alcohol effects on excitatory/inhibitory neurotransmission, rather than to hormonal or blood alcohol level differences.
Collapse
Affiliation(s)
- L M Veatch
- Research Service, Department of Veterans Affairs Medical Center, Charleston, South Carolina 29401-5799, USA.
| | | | | |
Collapse
|
14
|
Maher SA, Doty SB, Torzilli PA, Thornton S, Lowman AM, Thomas JD, Warren R, Wright TM, Myers E. Nondegradable hydrogels for the treatment of focal cartilage defects. J Biomed Mater Res A 2007; 83:145-55. [PMID: 17390320 DOI: 10.1002/jbm.a.31255] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [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: 11/08/2022]
Abstract
Nondegradable materials have long been suggested for the treatment of articular cartilage defects; however, the mechanics of the implant/tissue system necessary to ensure long-term function are unknown. The objective of this study was to explore the performance of nondegradable hydrogel implants in cartilage defects. Our hypothesis was that the structural integrity of the implant and surrounding tissue would be influenced by the compressive modulus of the material used, and that superior results would be obtained with the implantation of a more compliant material. Poly(vinyl alcohol)-poly(vinyl pyrrolidone) hydrogel implants of two different moduli were implanted into osteochondral defects in a rabbit model. Six-month postoperative histological and mechanical data were used to assess the wear and fixation of the implants. The compliant implants remained well fixed and a thin layer of soft tissue grew over the surface of the implants. However, gross deformation of the compliant implants occurred and debris was evident in surrounding bone. The stiffer implants were dislocated from their implantation site, but with no accompanying evidence of debris or implant deformation. Our hypothesis that superior results would be obtained with implantation of a more compliant material was rejected; a compromise between the wear and fixation properties dependent on modulus was found.
Collapse
Affiliation(s)
- S A Maher
- Hospital for Special Surgery, 535 East 70th Street, New York, New York 10021, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Abstract
Recent developments in the molecular biology of renal cell carcinoma have identified multiple pathways associated with the development of this cancer. Multiple strategies have been investigated targeting these pathways, with significant clinical benefits shown in early studies. This review aims to overview the findings of recent clinical trials and clarify the development of these compounds for use in renal cell carcinoma. The authors also aim to clarify the molecular pathways implicated in renal cell carcinoma and the clinical results in metastatic renal cell carcinoma with agents targeting these pathways. The relevant literature was reviewed concerning pathways implicated in the pathophysiology of renal cell carcinoma including pathways activated secondary to von Hippel-Lindau gene inactivation and PI-3 kinase/Akt/mammalian target of rapamycin pathway activation. Therapeutic targeting based upon underlying molecular biology in renal cell carcinoma has strong rationale. Substantial clinical activity has been reported with various agents targeting these pathways, most notably with vascular endothelial growth factor-targeted therapy. However, investigation is needed to optimally utilize these agents at the appropriate stage of disease and in the best combinations for maximal clinical benefit.
Collapse
Affiliation(s)
- W Kimryn Rathmell
- Lineberger Comprehensive Cancer Center, University of North Carolina, Campus Box 7295, Chapel Hill, NC 27599-7295, USA.
| | | | | |
Collapse
|
16
|
Fritton JC, Myers ER, Wright TM, van der Meulen MCH. Loading induces site-specific increases in mineral content assessed by microcomputed tomography of the mouse tibia. Bone 2005; 36:1030-8. [PMID: 15878316 DOI: 10.1016/j.bone.2005.02.013] [Citation(s) in RCA: 191] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2004] [Revised: 01/14/2005] [Accepted: 02/25/2005] [Indexed: 11/30/2022]
Abstract
Adaptation to mechanical loading has been studied extensively in cortical, but not cancellous bone. However, corticocancellous sites are more relevant to osteoporosis and related fracture risk of the hip and spine. We tested the hypotheses that adaptation in a long bone would be greater at cancellous than cortical sites and would depend on the term of daily in vivo cyclic axial loading. We applied compressive loads to the adolescent, 10-week old, male C57BL/6 mouse tibia to examine the skeletal response immediately prior to attainment of peak bone mass. Adaptation was quantified at the completion of either 2-week (n = 8) or 6-week (n = 12) loading terms by directly comparing volumetric bone mineral content between loaded and contralateral limbs by microcomputed tomography. The increase in mineral content was site specific with a greater response found in the corticocancellous proximal metaphysis (14%) than the cortical mid-shaft (2%) after 6 weeks of loading. Furthermore, bone volume fraction and average trabecular thickness of cancellous bone in the proximal tibia increased after 6 weeks by 15% and 12% respectively. Diaphyseal response was only evident proximal to the mid-shaft as indicated by an 8% increase in maximum principal moment of inertia. Both loading terms produced similar results for mineral content, volume fraction, and moments of inertia. Our finding that non-invasive loading increases the bone volume and fraction at a corticocancellous site by as much as 15% motivates exploring the use of mechanical loading to attain greater peak bone mass and inhibit osteoporosis.
Collapse
Affiliation(s)
- J C Fritton
- Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA.
| | | | | | | |
Collapse
|
17
|
Abstract
Classification and regression tree (CART) modelling was used to determine infectious hypodermal and haematopoietic necrosis virus (IHHNV) resistance and susceptibility in Penaeus stylirostris. In a previous study, eight random amplified polymorphic DNA (RAPD) markers and viral load values using real-time quantitative PCR were obtained and used as the training data set in order to create numerous regression tree models. Specifically, the genetic markers were used as categorical predictor variables and viral load values as the dependent response variable. To determine which model has the highest predictive accuracy for future samples, RAPD fingerprint data was generated from new Penaues stylirostris IHHNV resistant and susceptible individuals and used to test the regression models. The best performing tree was a four terminal node tree with three genetic markers as significant variables. Marker-assisted breeding practices may benefit from the creation of regression tree models that apply genetic markers as predictive factors. To our knowledge this is the first study to use RAPD markers as predictors within a CART prediction model to determine viral susceptibility.
Collapse
Affiliation(s)
- S E Hizer
- Department of Biological Sciences, California State University, San Marcos, CA 92026, USA
| | | | | |
Collapse
|
18
|
Abstract
Dendritic cells (DC) are antigen (Ag)-presenting cells that are essential for initiation of T cell-dependent immunity, and distinct DC subsets are known to direct different classes of immune responses. DC2 precursors (pDC2) or plasmacytoid DC were recently identified as a Th2-skewing and IFN-alpha-producing human DC subset. Here, we demonstrate that pDC2 enriched from human peripheral blood have a capacity to induce an anergic state in human Ag-specific CD4(+) T cell lines. Tetanus toxoid-specific T cell lines incubated with tetanus toxoid-pulsed autologous pDC2 failed to proliferate in secondary cultures with optimal Ag stimulation. T cell anergy induction required TCR engagement with Ag/MHC complex presented on pDC2. T cells rendered anergic lost IL-2 production but produced IFN-gamma and IL-10 upon stimulation. The pDC2-induced unresponsiveness was completely or partially reversible when a high concentration of exogenous IL-2 was added in the secondary cultures. Autoreactive CD4(+) T cell clones specific for topoisomerase I derived from a patient with scleroderma were also rendered anergic after co-culture with topoisomerase I-pulsed autologous pDC2,resulting in failure to proliferate or provide help to B cells. These results suggest that pDC2 are involved in maintenance of peripheral T cell tolerance and have potential for use in the suppression of pathogenic T cell responses in autoimmune diseases and organ transplantation.
Collapse
Affiliation(s)
- M Kuwana
- Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan.
| | | | | | | | | |
Collapse
|
19
|
Abstract
OBJECTIVE To examine T and B cell responses to topoisomerase I (topo I) in a monozygotic twin pair discordant for systemic sclerosis (SSc). METHODS The peripheral blood T cell proliferative responses induced by topo I and in vitro anti-topo I antibody production in cultures of T and B cells were examined in an SSc patient with serum anti-topo I antibody and in her healthy monozygotic twin. Topo I-reactive T cell lines were generated from the twin pair and analyzed for antigenic specificity, major histocompatibility complex class II restriction, and T cell receptor (TCR) gene usage. RESULTS T cell proliferative responses to topo I were detected in both the SSc patient and her healthy twin, although the kinetics of the T cell response were accelerated in the patient compared with the healthy twin. The estimated frequency of circulating topo I-reactive T cells was 1/6,700 in the SSc patient and 1/39,000 in the healthy twin. Anti-topo I antibody production was observed in cultures of T and B cells from the SSc patient, but not in those from the healthy twin. When the cells from the twins were mixed in different combinations, T cells from the healthy twin did stimulate the SSc patient's B cells to produce anti-topo I antibody through a CD40-dependent mechanism. Topo I-reactive T cell lines generated from the twins had similar characteristics, including a CD4+ phenotype, restriction by HLA-DR, recognition of epitopes within amino acid residues 209-386 of topo I, and dominant usage of the TCR Vbeta20 gene segment. CONCLUSION These results indicate that topo I-reactive T cells were activated and clonally expanded in the SSc patient. However, there were no substantial differences in either phenotypic or functional properties of topo I-reactive T cells obtained from the SSc patient and those obtained from her healthy identical twin. It is likely, therefore, that the anti-topo I antibody response in the SSc patient is induced by in vivo activation of topo I-reactive T cells derived from the normal T cell repertoire.
Collapse
Affiliation(s)
- M Kuwana
- University of Pittsburgh School of Medicine, Pennsylvania 15261, USA
| | | | | | | |
Collapse
|
20
|
Oriss TB, Hu PQ, Wright TM. Distinct autoreactive T cell responses to native and fragmented DNA topoisomerase I: influence of APC type and IL-2. J Immunol 2001; 166:5456-63. [PMID: 11313383 DOI: 10.4049/jimmunol.166.9.5456] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Systemic sclerosis (SSc) is an autoimmune connective tissue disease of unknown etiology in which T cell responses to various autoantigens, including DNA topoisomerase I (Topo I), have been implicated. We investigated whether dendritic cells, generally considered to be the most potent APCs for the initiation of immune responses, would present either of two forms of Topo I to T cells more efficiently than PBMC APCS: Using cells from healthy controls and SSc patients, several important observations were made. First, neither APC type was able to initiate T cell proliferative responses to full-length native Topo I unless exogenous IL-2 was added. This is in contrast to vigorous T cell proliferation in response to Topo I polypeptide fragments presented by either APC type. Second, T cell responses to the full-length form of Topo I presented by dendritic cells were considerably lower than responses to Ag presented by PBMC APCS: Finally, no secondary T cell responses were observed unless the same Ag/APC combination as that used in the primary stimulation was maintained. These data indicate that different peptides are generated based upon the form of the Topo I and the APC that processes it. Taken together, these results suggest that a very specific combination of antigenic form and APC may be involved in breaking tolerance to Topo I in the early stages of development of SSC:
Collapse
Affiliation(s)
- T B Oriss
- Division of Rheumatology and Clinical Immunology, University of Pittsburgh School of Medicine, University of Pittsburgh Arthritis Institute, Pittsburgh, PA 15261, USA
| | | | | |
Collapse
|
21
|
Abstract
Addison's crisis is the most serious complication of adrenal insufficiency. To elucidate the mechanism of this disorder following infection, the role of TNF in adrenalectomized murine models of Addison's crisis and Addison's disease (chronic hypoglucocorticoidism) were examined. Adrenalectomy conferred a 40-fold increased sensitivity to the lethal effects of lipopolysacharride (LPS) (P < .001). Enhanced sensitivity to LPS was found to increase with duration of adrenal insufficiency (P < .02). Enhanced lethality to heat-killed Streptococcus pneumonia was also demonstrated (P < 0.02). Necropsy of endotoxin-killed adrenalectomized mice demonstrated similar pathologic findings to those found by others when the control mice were administered a lethal dose of either LPS or TNF. Adrenalectomized TNF receptor Ia and Ib double null mice were demonstrated to be resistant to the lethal effects of LPS (P < 0.02). Pretreatment with anti-TNF, but not control antisera, was found to prevent death in LPS-treated wild-type adrenalectomized mice as well (P < 0.02). Studies into the mechanism by which TNF was precipitating Addison's crisis demonstrated enhanced sensitivity to TNF (3-fold; P < 0.02), and a marked increase in serum TNF concentration (approximately 5-fold; P < 0.001) following LPS challenge. The effect of TNF upon long-term survival in adrenalectomized mice was examined in TNF-receptor Ia- and Ib-deficient mice. Deficiencies in either the TNF-receptor Ia or Ib was noted to confer a survival advantage relative to colony controls following adrenalectomy (P < 0.02). In summary, both LPS-induced Addison's crisis and chronic adrenal insufficiency are disorders of TNF disregulation. Based upon these data, therapeutic strategies targeted at controlling TNF in adrenal insufficiency are suggested.
Collapse
Affiliation(s)
- L G Koniaris
- Department of Molecular Biology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | | | | |
Collapse
|
22
|
Kuwana M, Medsger TA, Wright TM. Analysis of soluble and cell surface factors regulating anti-DNA topoisomerase I autoantibody production demonstrates synergy between Th1 and Th2 autoreactive T cells. J Immunol 2000; 164:6138-46. [PMID: 10843663 DOI: 10.4049/jimmunol.164.12.6138] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The cellular and subcellular events governing Ab production with specificity for self Ags are poorly understood. In this study we examined the role of cellular interactions and cytokines in regulating the production of anti-DNA topoisomerase I (topo I) Ab, a major autoantibody in patients with systemic sclerosis (SSc). Topo I-specific T cell clones derived from SSc subjects and healthy donors were cultured with autologous peripheral blood B cells. Anti-topo I Ab production was induced by five of seven topo I-specific T cell clones derived from SSc subjects, but by none of eight T cell clones generated from healthy controls. However, two of the T cell clones from healthy controls provided help to HLA-DR-matched SSc B cells to produce anti-topo I Ab. The analysis of cytokine mRNA expression revealed that the ability to promote anti-topo I autoantibody production was strictly correlated with IL-2 and IL-6 expression by the T cell clones. Kinetic studies showed that IL-2 was required throughout the culture period for maximal autoantibody production and that both MHC-TCR and CD40-CD40L interactions were essential during the early phase of the culture. IL-6 was important in the late phase. Th1 clones (producing IL-2, but no IL-6) and Th2 clones (producing IL-6, but no IL-2) synergically activated autologous B cells to produce anti-topo I Ab. These results indicate that T cell-dependent B cell activation resulting in anti-topo I autoantibody production requires a series of temporally defined cell contact and soluble stimuli.
Collapse
Affiliation(s)
- M Kuwana
- Department of Medicine, University of Pittsburgh School of Medicine, PA 15261, USA
| | | | | |
Collapse
|
23
|
Vaughan JH, Shaw PX, Nguyen MD, Medsger TA, Wright TM, Metcalf JS, Leroy EC. Evidence of activation of 2 herpesviruses, Epstein-Barr virus and cytomegalovirus, in systemic sclerosis and normal skins. J Rheumatol 2000; 27:821-3. [PMID: 10743836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
|
24
|
Simonian PT, Levine RE, Wright TM, Wickiewicz TL, Warren RF. Response of hamstring and patellar tendon grafts for anterior cruciate ligament reconstruction during cyclic tensile loading. Am J Knee Surg 2000; 13:8-12. [PMID: 11826927] [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] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
The efficacy of anterior cruciate ligament (ACL) reconstruction in the knee using hamstring tendon or patellar tendon grafts is thought to depend on the relative amounts of graft elongation, or creep, following postoperative rehabilitation. In this study, the creep responses of the tendinous portions of these two graft types were compared during 1 hour of cyclic loading to 200 N at 1 Hz. In the hamstring tendon grafts, strains were measured in both the tissue and in the length-augmentation tape to identify the relative contribution of this particular graft fixation to overall creep. Differences in tissue strain between graft types during cyclic loading were not statistically significant. For both types of grafts, overall graft length significantly increased after 3600 cycles while tissue creep was not significant. The greatest creep in the hamstring tendon grafts occurred at the tissue-tape interface, indicating a potential disadvantage of this composite graft construct.
Collapse
Affiliation(s)
- P T Simonian
- Department of Orthopedic Surgery, The University of Washington, Seattle 98195, USA
| | | | | | | | | |
Collapse
|
25
|
Chen LC, Kepka-Lenhart D, Wright TM, Morris SM. Salicylate-enhanced activation of transcription factors induced by interferon-gamma. Biochem J 1999; 342 Pt 3:503-7. [PMID: 10477259 PMCID: PMC1220489] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Salicylate enhanced the interferon-gamma-dependent activation of two transcription factors in a murine macrophage cell line: signal transducer and activator of transcription (STAT)1 and interferon-gamma-responsive factor 1. Salicylate alone did not activate these transcription factors. This enhancement was reflected by increased DNA-binding activities and was the consequence of prolonged tyrosine phosphorylation of these transcription factors following interferon-gamma treatment. However, salicylate did not directly inhibit protein-tyrosine phosphatase activity in nuclear extracts of interferon-gamma-treated cells. The enhanced activation of STAT1 resulted in increased induction of mRNA encoding interferon regulatory factor-1. These results not only demonstrate that aspirin and its metabolite salicylate may have pro-inflammatory as well as anti-inflammatory effects but also raise the possibility that new cellular targets may be identified for modulating the Janus kinase-STAT signalling pathway.
Collapse
Affiliation(s)
- L C Chen
- Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | | | | | | |
Collapse
|
26
|
Affiliation(s)
- T M Wright
- Department of Biomechanics and Biomaterials, Hospital for Special Surgery, New York, New York 10021-4892, USA.
| | | | | |
Collapse
|
27
|
Abstract
OBJECTIVE To simultaneously identify several genes whose expression is altered in dermal fibroblasts from patients with systemic sclerosis (SSc). METHODS Total RNA was prepared from fibroblasts derived from clinically affected and unaffected skin of patients with SSc. The RNA samples were analyzed using differential-display reverse transcription-polymerase chain reaction (DDRT-PCR). Complementary DNA (cDNA) fragments corresponding to differentially expressed messenger RNAs (mRNAs) were eluted, cloned, and sequenced. The differential expression of the corresponding mRNAs was confirmed by ribonuclease protection assay. RESULTS We identified 21 differentially expressed mRNAs. Their corresponding cDNAs were sequenced and the sequences obtained were compared with those of known genes entered into the EMBL/GenBank database. Three of the sequences corresponded to transcripts of yet-unidentified genes. Some of the mRNAs shared partial homology with extracellular matrix components, cellular receptors, enzymes, and nuclear factors. Others corresponded to known mRNAs such as those of fibronectin, fibronectin receptor, laminin receptor homolog, beta-tubulin, insulin-like growth factor binding protein 5, KIAA0179 protein, and protease nexin 1. CONCLUSION The application of DDRT-PCR to scleroderma research has identified many mRNAs whose altered expression in scleroderma has not yet been described, thus providing new information for further investigation and potential targets for the development of novel therapies.
Collapse
Affiliation(s)
- C A Feghali
- University of Pittsburgh, Pennsylvania 15261, USA
| | | |
Collapse
|
28
|
Kuwana M, Kaburaki J, Medsger TA, Wright TM. An immunodominant epitope on DNA topoisomerase I is conformational in nature: heterogeneity in its recognition by systemic sclerosis sera. Arthritis Rheum 1999; 42:1179-88. [PMID: 10366110 DOI: 10.1002/1529-0131(199906)42:6<1179::aid-anr14>3.0.co;2-e] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE To characterize an immunodominant epitope recognized by anti-DNA topoisomerase I (topo I) antibody, a major autoantibody in sera of patients with systemic sclerosis (SSc). METHODS Topo I fragments were generated as fusion proteins using a bacterial expression system as well as polypeptides translated in vitro using a eukaryotic expression system. Reactivities to the 2 preparations of recombinant topo I polypeptides in anti-topo I-positive sera from SSc patients of varied ethnic backgrounds were examined by immunoblotting, immunoprecipitation, and/or enzyme-linked immunosorbent assay. RESULTS The fragment encoding amino acids 489-573 of topo I was recognized by 98 of 100 anti-topo I-positive SSc sera. Both carboxyl- and amino-terminal deletion studies as well as competitive inhibition assays using topo I synthetic peptides showed that a region of > or =52 amino acids (512-563) was necessary for recognition by anti-topo I antibodies. The minimum epitope region and conformation required for this reactivity were variable among sera from Caucasian, African American, Japanese, and Choctaw SSc patients. CONCLUSION An immunodominant epitope recognized by anti-topo I autoantibody is located in the region of amino acids 489-573 of the topo I protein and is largely conformational in nature. The recognition pattern of this region by anti-topo I-positive sera is heterogeneous and is influenced by ethnic background.
Collapse
Affiliation(s)
- M Kuwana
- University of Pittsburgh School of Medicine, Pennsylvania 15213, USA
| | | | | | | |
Collapse
|
29
|
Abstract
It is reported that fibroblasts derived from clinically affected skin areas of patients with systemic sclerosis (SSc) have the ability to overproduce several cytokines and growth factors (i.e., IL-6, PDGF), an ability that might be involved in the pathogenesis of SSc. We have previously shown that the expression of IL-1alpha was constitutively observed in SSc fibroblasts, whereas this was not detected in normal fibroblasts. Although it was suggested that the aberrant IL-1alpha production could be associated with the fibrogenic phenotype of SSc fibroblasts, little is known about the roles of IL-1alpha in SSc fibroblasts. IL-1alpha induced IL-6 and PDGF-A, which are potent stimulators of collagen production and proliferation in normal fibroblasts. This article examines the proposal that IL-6 and PDGF-A are elevated through the action of endogenous IL-1alpha in SSc fibroblasts. An antisense oligodeoxynucleotide complementary to IL-1alpha mRNA was used to suppress endogenous IL-1alpha. Inhibition of endogenous IL-1alpha led to decreased levels of IL-6 and PDGF-A expression in SSc fibroblasts. Moreover, the blocking of the IL-6 response using anti-IL-6 antibody resulted in a significant reduction of procollagen type I in cultured SSc fibroblasts. These results suggest that endogenous IL-1alpha expressed by SSc fibroblasts may play a key role in the abnormal function of SSc fibroblasts through the expression of IL-6 and PDGF-A.
Collapse
Affiliation(s)
- Y Kawaguchi
- Division of Rheumatology and Clinical Immunology, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213,
| | | | | |
Collapse
|
30
|
Kuwana M, Kaburaki J, Arnett FC, Howard RF, Medsger TA, Wright TM. Influence of ethnic background on clinical and serologic features in patients with systemic sclerosis and anti-DNA topoisomerase I antibody. Arthritis Rheum 1999; 42:465-74. [PMID: 10088769 DOI: 10.1002/1529-0131(199904)42:3<465::aid-anr11>3.0.co;2-y] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To investigate the effect of ethnicity on clinical and serologic expression in patients with systemic sclerosis (SSc) and anti-DNA topoisomerase I (anti-topo I) antibody. METHODS Clinical and serologic features, as well as HLA class II allele frequencies, were compared among 47 North American white, 15 North American black, 43 Japanese, and 12 Choctaw Native American SSc patients with anti-topo I antibody. RESULTS The frequency of progressive pulmonary interstitial fibrosis was lower, and cumulative survival rates were better in white compared with black and Japanese patients. Sera of white and black patients frequently recognized the portion adjacent to the carboxyl terminus of topo I, sera of Japanese patients preferentially recognized the portion adjacent to the amino terminus of topo I, and sera of Choctaw patients recognized both portions of topo I. Anti-RNA polymerase II and anti-SSA/Ro antibodies were present together with anti-topo I antibody more frequently in sera of Japanese patients than in sera of white patients. The HLA-DRB1 alleles associated with anti-topo I antibody differed; i.e., DRB1*1101-*1104 in whites and blacks, DRB1*1502 in Japanese, and DRB1*1602 in Choctaws. Multivariate analysis showed that ethnic background was an independent determinant affecting development of severe lung disease as well as survival. CONCLUSION Clinical and serologic features in SSc patients were strongly influenced by ethnic background. The variability of disease expression in the 4 ethnic groups suggests that multiple factors linked to ethnicity, including genetic and environmental factors, modulate clinical manifestations, disease course, and autoantibody status in SSc.
Collapse
MESH Headings
- Adult
- Aged
- Alleles
- Antibodies, Antinuclear/analysis
- Antibodies, Antinuclear/immunology
- Antibody Specificity
- Asian People
- B-Lymphocytes/immunology
- DNA Topoisomerases, Type I/immunology
- Disease Progression
- Epitopes/immunology
- Female
- HLA-DQ Antigens/genetics
- HLA-DQ Antigens/immunology
- HLA-DQ beta-Chains
- HLA-DR Antigens/genetics
- HLA-DR Antigens/immunology
- HLA-DRB1 Chains
- Histocompatibility Antigens Class II/analysis
- Histocompatibility Antigens Class II/immunology
- Humans
- Immunoglobulin A/blood
- Immunoglobulin G/blood
- Immunoglobulin M/blood
- Indians, North American
- Japan
- Lung Diseases, Interstitial/ethnology
- Lung Diseases, Interstitial/immunology
- Lung Diseases, Interstitial/mortality
- Male
- Middle Aged
- Multivariate Analysis
- Prognosis
- Random Allocation
- Scleroderma, Systemic/ethnology
- Scleroderma, Systemic/immunology
- Scleroderma, Systemic/mortality
- Survival Analysis
- White People
Collapse
Affiliation(s)
- M Kuwana
- University of Pittsburgh School of Medicine, Pennsylvania, USA
| | | | | | | | | | | |
Collapse
|
31
|
Affiliation(s)
- A L Boskey
- Mineralized Tissue Research Section, Research Division, Hospital for Special Surgery, New York, NY, USA
| | | | | |
Collapse
|
32
|
Kuwana M, Okano Y, Kaburaki J, Medsger TA, Wright TM. Autoantibodies to RNA polymerases recognize multiple subunits and demonstrate cross-reactivity with RNA polymerase complexes. Arthritis Rheum 1999; 42:275-84. [PMID: 10025921 DOI: 10.1002/1529-0131(199902)42:2<275::aid-anr9>3.0.co;2-p] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE To determine the subunit specificity of autoantibody directed to RNA polymerases (RNAP) I, II, and III, which is one of the major autoantibody responses in patients with systemic sclerosis (SSc). METHODS Thirty-two SSc sera with anti-RNAP antibodies (23 with anti-RNAP I/III, 5 with anti-RNAP I/III and II, and 4 with anti-RNAP II alone) were analyzed by immunoblotting using affinity-purified RNAP and by immunoprecipitation using 35S-labeled cell extracts in which RNAP complexes were dissociated. Antibodies bound to individual RNAP subunits were eluted from preparative immunoblots and were further analyzed by immunoblotting and immunoprecipitation. RESULTS At least 15 different proteins were bound by antibodies in anti-RNAP-positive SSc sera in various combinations. All 9 sera immunoprecipitating RNAP II and all 28 sera immunoprecipitating RNAP I/III recognized the large subunit proteins of RNAP II and III, respectively. Reactivity to RNAP I large subunits was strongly associated with bright nucleolar staining by indirect immunofluorescence. Affinity-purified antibodies that recognized a 62-kd subunit protein cross-reacted with a 43-kd subunit protein and immunoprecipitated both RNAP I and RNAP III. Antibodies that recognized a 21-kd subunit protein obtained from sera that were positive for anti-RNAP I/III and II antibodies immunoprecipitated both RNAP II and RNAP III. CONCLUSION Anti-RNAP antibodies recognize multiple subunits of RNAP I, II, and III. Moreover, the results of this study provide the first direct evidence that antibodies that recognize shared subunits of human RNAPs or epitopes present on different human RNAP subunits are responsible for the recognition of multiple RNAPs by SSc sera.
Collapse
Affiliation(s)
- M Kuwana
- University of Pittsburgh School of Medicine, Pennsylvania, USA
| | | | | | | | | |
Collapse
|
33
|
Schildhauer TA, Bennett AP, Wright TM, Lane JM, O'Leary PF. Intravertebral body reconstruction with an injectable in situ-setting carbonated apatite: biomechanical evaluation of a minimally invasive technique. J Orthop Res 1999; 17:67-72. [PMID: 10073649 DOI: 10.1002/jor.1100170111] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The ability to mechanically reinforce an osteoporotic vertebral body could impede spinal compression fracture and the associated pain and complications. Previous studies have shown that reinforcement of fractured vertebrae with conventional acrylic cement can relieve symptoms and avoid further collapse. In this study, we explored the use of a carbonated apatite cement combined with a minimally invasive injection technique to improve the compressive mechanical properties of cadaveric vertebral bodies. After establishing the biomechanical characteristics of cement formulations intended to have appropriate viscosities, we evaluated the infiltration of the cements into thoracic vertebral bodies using a combined suction-injection technique. The energy-absorption capabilities of the reinforced vertebral bodies were then measured during axial compressive tests and compared with those of nonreinforced vertebrae. The ultimate compressive strength of the cement formulations averaged from 11.6 to 17.7 MPa, depending on curing conditions. The suction-injection technique allowed from one-half to two-thirds of each vertebral body to be infiltrated with cement. Energy absorption was significantly higher (p < 0.05) between 25 and 70% collapse of the vertebral body in the specimens that received the apatite injection as compared with the controls. These results suggest that osteoporotic vertebral-body augmentation with the injection of apatite cement could prevent further collapse after initial failure has occurred. The osteoconductive nature of the cement and its ability to be remodeled by bone, together with its compressive strength, which is higher than that of cancellous bone, could provide better clinical results than those of current treatments with acrylic cement.
Collapse
Affiliation(s)
- T A Schildhauer
- Department of General and Trauma Surgery, BG-Kliniken Bergmannsheil, Ruhr-Universitaet, Bochum, Germany.
| | | | | | | | | |
Collapse
|
34
|
Horton MR, McKee CM, Bao C, Liao F, Farber JM, Hodge-DuFour J, Puré E, Oliver BL, Wright TM, Noble PW. Hyaluronan fragments synergize with interferon-gamma to induce the C-X-C chemokines mig and interferon-inducible protein-10 in mouse macrophages. J Biol Chem 1998; 273:35088-94. [PMID: 9857043 DOI: 10.1074/jbc.273.52.35088] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.2] [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: 02/04/2023] Open
Abstract
Hallmarks of chronic inflammation and tissue fibrosis are increased influx of activated inflammatory cells, mediator release, and increased turnover and production of the extracellular matrix (ECM). Recent evidence has suggested that fragments of the ECM component hyaluronan play a role in chronic inflammation by inducing macrophage expression of chemokines. Interferon-gamma (IFN-gamma), an important regulator of macrophage functions, has been shown to induce the C-X-C chemokines Mig and IP-10. These chemokines affect T-cell recruitment and inhibit angiogenesis. The purpose of this investigation was to determine the effect of hyaluronan (HA) on IFN-gamma-induced Mig and IP-10 expression in mouse macrophages. We found a marked synergy between HA and IFN-gamma on Mig and IP-10 mRNA and protein expression in mouse macrophages. This was most significant with Mig, which was not induced by HA alone. The synergy was specific for HA, was not dependent on new protein synthesis, was not mediated by tumor necrosis factor-alpha, was selective for Mig and IP-10, and occurred at the level of gene transcription. These data suggest that the ECM component HA may influence chronic inflammatory states by working in concert with IFN-gamma to alter macrophage chemokine expression.
Collapse
Affiliation(s)
- M R Horton
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
|
36
|
Gómez-Barrena E, Li S, Furman BS, Masri BA, Wright TM, Salvati EA. Role of polyethylene oxidation and consolidation defects in cup performance. Clin Orthop Relat Res 1998:105-17. [PMID: 9678038] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Quality factors such as particle consolidation and oxidation have been claimed to impair the performance of ultrahigh molecular weight polyethylene implants, but no definite data estimate their real effect. To assess the influence of these quality determinants in wear, wear rate, and time in service at a single, well proven design, the percentage area of polyethylene sections occupied by nonconsolidated polyethylene particles, the presence of a white band, and the amount of polyethylene oxidation (through density curves) were evaluated in 92 retrieved Charnley acetabular components with available clinical data. The average percentage area of nonconsolidated polyethylene particles in cup sections was 3.1%. There were 11 cups showing a subsurface white band. The authors observed an average density in the deep polyethylene of 0.9420 g/cc after an average in vivo use of 9.8 years (range, 0.08-20.3 years). Banded cups showed significantly higher subsurface densities. When studying the relationship among clinical and material factors with performance variables, wear measurements (obtained through radiographic methods and direct measurements of polyethylene thickness in the collected implants) correlated with age at implantation, activity, and time in service. Weight was a determinant of the wear rate. None of the studied polyethylene quality factors showed a definite association with wear performance or time to failure in this series. Implant survivorship was not significantly impaired in the 22.225-mm Charnley low friction replacement by a subsurface white band or by a higher area occupied by nonconsolidated particles. Fewer nonconsolidated particles were not associated with longer survivorship. This design proved tolerance to polyethylene quality variations, in the signaled ranges, without a significant effect in the system performance.
Collapse
Affiliation(s)
- E Gómez-Barrena
- Department of Orthopaedic Surgery and Traumatology, Nuestra Señora de Gracia, Zaragoza, Spain
| | | | | | | | | | | |
Collapse
|
37
|
Estupiñán JA, Bartel DL, Wright TM. Residual stresses in ultra-high molecular weight polyethylene loaded cyclically by a rigid moving indenter in nonconforming geometries. J Orthop Res 1998; 16:80-8. [PMID: 9580258 DOI: 10.1002/jor.1100160114] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The characterization of stress and deformation fields that incorporate moving cyclic loads and nonlinear material response in ultra-high molecular weight polyethylene components for total knee replacements is required to quantify mechanisms of surface damage. A simulation of stresses in polyethylene components for total knee replacement subjected to cyclic moving loads was performed with use of nonlinear finite element analysis. Convergence to a steady-state cycle of stress and deformation was observed within five cycles of loading. Differential plastic deformation under the surface of the polyethylene led to horizontal residual stresses that were tensile at the surface and compressive in the subsurface. The magnitudes of the residual stresses indicate their importance in surface failure mechanisms. Horizontal residual tensile stresses at the surface are consistent with the initiation and propagation of surface cracks that could cause pitting in polyethylene. Horizontal residual compressive stresses under the surface could cause such cracks to arrest or turn and thus limit damage to a region just beneath the surface. The results emphasize the importance of incorporating nonlinear effects to simulate long-term stress fields associated with surface damage in polyethylene.
Collapse
Affiliation(s)
- J A Estupiñán
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, New York 14853, USA.
| | | | | |
Collapse
|
38
|
|
39
|
Kuwana M, Medsger TA, Wright TM. Highly restricted TCR-alpha beta usage by autoreactive human T cell clones specific for DNA topoisomerase I: recognition of an immunodominant epitope. The Journal of Immunology 1997. [DOI: 10.4049/jimmunol.158.1.485] [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: 01/01/2023]
Abstract
Abstract
Autoantibody responses to DNA topoisomerase I (Topo I) are highly specific to patients with systemic sclerosis (SSc). We recently demonstrated that Topo I-specific T cells are components of the T cell repertoire of patients with SSc and healthy individuals. These autoreactive T cells were essential for the Ag-specific activation of B cells resulting in anti-Topo I Ab production in vitro and therefore are believed to play a central role in autoantibody production. To characterize the Topo I-specific T cell, 15 T cell clones reactive with Topo I were generated from two patients with SSc and three healthy donors, all of whom shared the MHC class II allele DR11. All clones expressed a CD3+CD4+CD8- phenotype and were restricted by HLA-DR. When eight rTopo I fragments were tested individually as Ags, all clones responded to F5, which encodes amino acids 209 through 386 of Topo I, but not to F10, which encodes amino acids 209 through 276, indicating that one or more immunodominant epitopes on Topo I is located between amino acids 276 and 386. Analysis of TCR gene usage showed that the predominant V(alpha) segment of the functionally rearranged TCR-alpha gene was Vdelta5, which was used by seven clones. Most strikingly, all except one T cell clone had functional rearrangements of TCR beta-chain genes using the Vbeta120.la and Jbeta1.1 gene segments. Comparison of the CDR3 sequences of the TCRs revealed limited diversity, and, of note, all clones contained the amino acid motif PGGN (or minor variations) in the CDR3 of their TCR beta-chains. Furthermore, identical beta-chain CDR3 amino acid sequences were encoded by cDNAs generated from T cell clones derived from multiple individuals, including patients with SSc and healthy donors.
Collapse
Affiliation(s)
- M Kuwana
- Department of Medicine, University of Pittsburgh School of Medicine, PA 15213, USA
| | - T A Medsger
- Department of Medicine, University of Pittsburgh School of Medicine, PA 15213, USA
| | - T M Wright
- Department of Medicine, University of Pittsburgh School of Medicine, PA 15213, USA
| |
Collapse
|
40
|
Kuwana M, Medsger TA, Wright TM. Highly restricted TCR-alpha beta usage by autoreactive human T cell clones specific for DNA topoisomerase I: recognition of an immunodominant epitope. J Immunol 1997; 158:485-91. [PMID: 8977226] [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] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Autoantibody responses to DNA topoisomerase I (Topo I) are highly specific to patients with systemic sclerosis (SSc). We recently demonstrated that Topo I-specific T cells are components of the T cell repertoire of patients with SSc and healthy individuals. These autoreactive T cells were essential for the Ag-specific activation of B cells resulting in anti-Topo I Ab production in vitro and therefore are believed to play a central role in autoantibody production. To characterize the Topo I-specific T cell, 15 T cell clones reactive with Topo I were generated from two patients with SSc and three healthy donors, all of whom shared the MHC class II allele DR11. All clones expressed a CD3+CD4+CD8- phenotype and were restricted by HLA-DR. When eight rTopo I fragments were tested individually as Ags, all clones responded to F5, which encodes amino acids 209 through 386 of Topo I, but not to F10, which encodes amino acids 209 through 276, indicating that one or more immunodominant epitopes on Topo I is located between amino acids 276 and 386. Analysis of TCR gene usage showed that the predominant V(alpha) segment of the functionally rearranged TCR-alpha gene was Vdelta5, which was used by seven clones. Most strikingly, all except one T cell clone had functional rearrangements of TCR beta-chain genes using the Vbeta120.la and Jbeta1.1 gene segments. Comparison of the CDR3 sequences of the TCRs revealed limited diversity, and, of note, all clones contained the amino acid motif PGGN (or minor variations) in the CDR3 of their TCR beta-chains. Furthermore, identical beta-chain CDR3 amino acid sequences were encoded by cDNAs generated from T cell clones derived from multiple individuals, including patients with SSc and healthy donors.
Collapse
Affiliation(s)
- M Kuwana
- Department of Medicine, University of Pittsburgh School of Medicine, PA 15213, USA
| | | | | |
Collapse
|
41
|
Abstract
Inflammation is mediated by a variety of soluble factors, including a group of secreted polypeptides known as cytokines. Inflammatory cytokines can be divided into two groups: those involved in acute inflammation and those responsible for chronic inflammation. This review describes the role played in acute inflammation by IL-1, TNF-alpha, IL-6, IL-11, IL-8 and other chemokines, G-CSF, and GM-CSF. It also describes the involvement of cytokines in chronic inflammation. This latter group can be subdivided into cytokines mediating humoral responses such as IL-4, IL-5, IL-6, IL-7, and IL-13, and those mediating cellular responses such as IL-1, IL-2, IL-3, IL-4, IL-7, IL-9, IL-10, IL-12, interferons, transforming growth factor-beta, and tumor necrosis factor alpha and beta. Some cytokines, such as IL-1, significantly contribute to both acute and chronic inflammation. This review also summarizes features of the cell-surface receptors that mediate the inflammatory effects of the described cytokines.
Collapse
Affiliation(s)
- C A Feghali
- Division of Rheumatology and Clinical Immunology, Department of Medicine, University of Pittsburgh, E1109 Biomedical Science Tower, 200 Lothrop St., Pittsburgh, PA 15261, USA.
| | | |
Collapse
|
42
|
Li EC, Ritter MA, Montgomery T, Furman BD, Li S, Wright TM. Catastrophic failure of a conforming type of total knee replacement: a case report. Clin Orthop Relat Res 1996:234-8. [PMID: 8981901] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A case study is presented to illustrate the concept of femoral component failure secondary to polyethylene wear in a 67 year old man, 13 years after he had conforming type total knee replacements. This case illustrates the theory that this observed problem may be a leading cause of failure in conforming and nonconforming total knee replacements in the future.
Collapse
Affiliation(s)
- E C Li
- Center for Hip and Knee Surgery, Mooresville, IN 46158, USA
| | | | | | | | | | | |
Collapse
|
43
|
Abstract
This study was designed to isolate and evaluate the parameters of host density, outer diameter (OD), root diameter (RD), and pitch in cancellous bone screw design and their effect on holding power. Special emphasis was placed on screw pitch, which has been evaluated infrequently in the literature. Three groups of stainless steel V thread screws (group I, OD 4.5 mm, RD 3.0 mm; group II, OD 6.4 mm, RD 3.5 mm; group III, OD 6.4 mm, RD 4.2 mm) were machined with progressive increases in pitch from 12 to 32 threads per inch (TPI). Two densities of synthetic cancellous bone material (Pedilen, Ottobock, Minneapolis, MN, U.S.A.), 0.15 g/ml and 0.22 g/ml, were then prepared and molded into sheets 1.9 cm thick and the screw threads completely engaged. Push-out tests were performed using a servohydraulic testing machine (MTS, Minneapolis, MN, U.S.A.). Fifteen trials of each screw were tested in each material. The effect on holding power of the different parameters of the custom screws in order of importance was (a) host material density, (b) OD (c) pitch, and (d) RD. The groups with a 6.4-mm OD had a much greater holding power than did the group with a 4.5-mm OD (p < 0.001). A decrease in screw pitch (increased threads per inch) did itself have a significant improved effect on fixation for all groups in both pedilen densities (p < 0.001). In the two 6.4-mm screw groups studied, the difference in the two root diameters (4.2 mm vs. 3.5 mm) showed the smaller root diameter to give a greater holding power in the less dense 0.15 g/ml pedilen (p < 0.001). In the more dense 0.22 g/ml pedilen there was no difference (p = 0.26) between the root diameters. To optimize holding power, cancellous screws may be designed with a decreased pitch (increased TPI) over those commercially available today. Cannulated screws must have a larger cancellous thread root diameter to leave room for the central cannulation; this may decrease their holding power in less dense cancellous bone but not in denser bone.
Collapse
Affiliation(s)
- S E Asnis
- Department of Biomechanics, Hospital for Special Surgery, New York, New York, USA
| | | | | | | | | | | | | |
Collapse
|
44
|
Evans CH, Robbins PD, Ghivizzani SC, Herndon JH, Kang R, Bahnson AB, Barranger JA, Elders EM, Gay S, Tomaino MM, Wasko MC, Watkins SC, Whiteside TL, Glorioso JC, Lotze MT, Wright TM. Clinical trial to assess the safety, feasibility, and efficacy of transferring a potentially anti-arthritic cytokine gene to human joints with rheumatoid arthritis. Hum Gene Ther 1996; 7:1261-80. [PMID: 8793551 DOI: 10.1089/hum.1996.7.10-1261] [Citation(s) in RCA: 186] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
- C H Evans
- Department of Molecular Genetics & Biochemistry, University of Pittsburgh School of Medicine, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Tweardy DJ, Wright TM, Ziegler SF, Baumann H, Chakraborty A, White SM, Dyer KF, Rubin KA. Granulocyte colony-stimulating factor rapidly activates a distinct STAT-like protein in normal myeloid cells. Blood 1995; 86:4409-16. [PMID: 8541528] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Binding of granulocyte colony-stimulating factor (G-CSF) to normal myeloid cells activates the protein tyrosine kinases Lyn and Syk and results in the immediate early upregulation of G-CSF receptor (R) mRNA. In our studies of the signaling pathways activated by G-CSF that are coupled to proliferation and differentiation of myeloid cells, we examined whether G-CSF activated a latent transcription factor belonging to the STAT protein family. Electrophoretic mobility shift assays (EMSAs) of nuclear extracts from G-CSF-stimulated human myeloid cells showed the rapid activation of a DNA-binding protein that bound to the high-affinity serum-inducible element (hSIE) and migrated with mobility similar to serum inducible factor (SIF)-A (Stat3 homodimer). The G-CSF-stimulated SIF-A complex (G-SIF-A) did not bind to duplex oligonucleotides used to purify and characterize other Stat proteins (Stat1-6). In addition, antibodies raised against Stat1-6 failed to supershift the G-SIF-A complex or interfere with its formation. Based on its binding to the hSIE and lack of antigenic cross-reactivity with other known STAT proteins that bind to this element, it is likely that G-SIF-A is composed of a distinct member of the STAT protein family. EMSAs of whole-cell extracts prepared from cell lines containing full-length and truncated mutants of the G-CSFR showed that activation of G-SIF-A did not correlate with proliferation; rather, optimal activation requires the distal half of the cytosolic domain of the G-CSFR that is essential for differentiation. Activation of G-SIF-A, therefore, may be an early G-CSFR-coupled event that is critical for myeloid maturation.
Collapse
Affiliation(s)
- D J Tweardy
- Department of Medicine, University of Pittsburgh School of Medicine, PA, USA
| | | | | | | | | | | | | | | |
Collapse
|
46
|
Li S, Chang JD, Barrena EG, Furman BD, Wright TM, Salvati E. Nonconsolidated polyethylene particles and oxidation in Charnley acetabular cups. Clin Orthop Relat Res 1995:54-63. [PMID: 7554650] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Nonconsolidated particles of ultra high molecular weight polyethylene are believed to be defects that adversely can affect the wear performance of total joint prostheses. The present study was done to determine the number, size, and distribution of these particles and to determine if their presence correlated with wear performance, as well as with other clinical and implant parameters. Forty retrieved and 7 new, never-implanted acetabular components were examined using light microscopy on thin cross sections. Particles were found in 92% of retrieved components and in all the new components. Particles in the retrieved components were either randomly distributed (32 components) or banded (with particles localized in regions approximately 1 mm below the outer surface of the component). No correlations were found between the number or area of particles and the wear performance or any of the clinical or implant variables. The presence of particles in the new implants was found to correlate with the length of time since the components had been radiation sterilized. For retrieved components, the density (and, therefore, the level of oxidative degradation) was high in the areas of banded particles. For new components, the density was higher the longer the time since sterilization. Nonconsolidated polyethylene particles are prevalent in total replacements but their source and cause are unknown. The results of this study show that they do not appear to affect or correlate with the length of implantation of acetabular cups. However, they still may be expected to adversely affect performance in cases where large numbers of particles are banded together near articulating surfaces of high stress environments such as found in the knee.
Collapse
Affiliation(s)
- S Li
- Department of Biomechanics and Biomaterials, Hospital for Special Surgery, New York, NY 10021, USA
| | | | | | | | | | | |
Collapse
|
47
|
Guyer NB, Severns CW, Wong P, Feghali CA, Wright TM. IFN-gamma induces a p91/Stat1 alpha-related transcription factor with distinct activation and binding properties. The Journal of Immunology 1995. [DOI: 10.4049/jimmunol.155.7.3472] [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: 01/01/2023]
Abstract
Abstract
The 5' flanking region of the mig gene, a member of the chemokine family of small m.w. chemoattractant and growth regulatory factors, contains an IFN-gamma-responsive enhancer, gamma RE-1, consisting of an extended imperfect palindrome. In this report we show that a novel factor, gamma RF-1, which binds to the gamma RE-1 element, is rapidly activated in a variety of primary cell types and tumor cell lines treated with IFN-gamma. Our data indicate that gamma RF-1 is present in a latent form in unstimulated cells and its DNA-binding activity is dependent upon tyrosine phosphorylation. UV cross-linking studies revealed that gamma RF-1 consists of at least two proteins of approximately 95 and 130 kDa, which interact with the gamma RE-1 element. A comparison of gamma RF-1 and GAF, an IFN-gamma-activated transcription factor containing the p91/Stat1 alpha protein (Stat, signal transducer and activator of transcription), showed that these two factors exhibited differences in electrophoretic mobility, responsiveness to IFN-alpha, and kinetics of activation. Using anti-Stat Ab, however, we found that one or more subunits of gamma RF-1 are antigenically related to p91/Stat1 alpha. Our results indicate, therefore, that gamma RF-1 and GAF are distinct IFN-gamma-responsive transcription factors and probably contain closely related members of the Stat protein family.
Collapse
Affiliation(s)
- N B Guyer
- Department of Medicine, University of Pittsburgh School of Medicine, PA, USA
| | - C W Severns
- Department of Medicine, University of Pittsburgh School of Medicine, PA, USA
| | - P Wong
- Department of Medicine, University of Pittsburgh School of Medicine, PA, USA
| | - C A Feghali
- Department of Medicine, University of Pittsburgh School of Medicine, PA, USA
| | - T M Wright
- Department of Medicine, University of Pittsburgh School of Medicine, PA, USA
| |
Collapse
|
48
|
Guyer NB, Severns CW, Wong P, Feghali CA, Wright TM. IFN-gamma induces a p91/Stat1 alpha-related transcription factor with distinct activation and binding properties. J Immunol 1995; 155:3472-80. [PMID: 7561042] [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] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The 5' flanking region of the mig gene, a member of the chemokine family of small m.w. chemoattractant and growth regulatory factors, contains an IFN-gamma-responsive enhancer, gamma RE-1, consisting of an extended imperfect palindrome. In this report we show that a novel factor, gamma RF-1, which binds to the gamma RE-1 element, is rapidly activated in a variety of primary cell types and tumor cell lines treated with IFN-gamma. Our data indicate that gamma RF-1 is present in a latent form in unstimulated cells and its DNA-binding activity is dependent upon tyrosine phosphorylation. UV cross-linking studies revealed that gamma RF-1 consists of at least two proteins of approximately 95 and 130 kDa, which interact with the gamma RE-1 element. A comparison of gamma RF-1 and GAF, an IFN-gamma-activated transcription factor containing the p91/Stat1 alpha protein (Stat, signal transducer and activator of transcription), showed that these two factors exhibited differences in electrophoretic mobility, responsiveness to IFN-alpha, and kinetics of activation. Using anti-Stat Ab, however, we found that one or more subunits of gamma RF-1 are antigenically related to p91/Stat1 alpha. Our results indicate, therefore, that gamma RF-1 and GAF are distinct IFN-gamma-responsive transcription factors and probably contain closely related members of the Stat protein family.
Collapse
Affiliation(s)
- N B Guyer
- Department of Medicine, University of Pittsburgh School of Medicine, PA, USA
| | | | | | | | | |
Collapse
|
49
|
Kuwana M, Medsger TA, Wright TM. T and B cell collaboration is essential for the autoantibody response to DNA topoisomerase I in systemic sclerosis. J Immunol 1995; 155:2703-14. [PMID: 7650398] [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] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To elucidate the mechanisms controlling anti-DNA topoisomerase I (topo I) antibody production in patients with systemic sclerosis (SSc), in particular the role of interactions between topo I-specific Th cells and B cells, we established an in vitro system for the analysis of anti-topo I antibody production. In vitro anti-topo I antibody synthesis in PBMC cultures was induced by recombinant topo I and PWM, and was measured by a topo I-specific ELISA. Anti-topo I antibody was detected in PBMC culture supernatants from 11 (61%) of 18 anti-topo I-positive SSc patients. In contrast, anti-topo I antibody was not detected in the PBMC culture supernatants from 4 anti-topo I-negative SSc patients or 10 healthy donors. Characterization of in vitro anti-topo I antibody production showed that 1) the anti-topo I antibody isotype produced was IgG; 2) the anti-topo I antibody levels in culture supernatants correlated with those in patients' sera; 3) CD4+ T cells were necessary for antibody synthesis; and 4) antibody synthesis was restricted by HLA-DR, but not by HLA-DQ or DP. In addition, separation of cultured T and B cells by a semipermeable membrane or culture with anti-CD40 ligand mAb blocked in vitro anti-topo I antibody production. These results indicate that a contact-mediated and HLA-DR-restricted collaboration between topo I-specific T and B cells is essential for in vitro anti-topo I antibody production in a subset of SSc patients.
Collapse
Affiliation(s)
- M Kuwana
- Department of Medicine, University of Pittsburgh School of Medicine, PA 15213, USA
| | | | | |
Collapse
|
50
|
Abstract
gamma RF-1 is a recently identified transcription factor induced by interferon-gamma (IFN-gamma) which binds to a unique palindromic enhancer, gamma RE-1, in the promoter of the mig gene. This paper describes the ligand-dependent and ligand-independent activation of gamma RF-1 in a cell-free system. gamma RF-1 activity was induced by IFN-gamma in a time-dependent manner from 5 to 60 min in lysates prepared from the human monocytic leukaemia line THP-1 and the human epidermoid carcinoma line A431. The activation of gamma RF-1 in vitro required both ATP and an inhibitor of tyrosine phosphatases (sodium orthovanadate or pervanadate). In the presence of limiting concentrations (micromolar) of ATP, activation was also dependent upon stimulation with IFN-gamma, whereas at millimolar concentrations of ATP, gamma RF-1 was activated by either sodium orthovanadate or pervanadate in the absence of ligand. Based on cell fractionation studies, both membrane and cytosol components were essential for activation of gamma RF-1 in vitro. Consistent with a role for one or more tyrosine kinases in the activation of gamma RF-1, its DNA binding activity was blocked by monoclonal anti-phosphotyrosine antibodies and by the tyrosine kinase inhibitors genistein, lavendustin A and herbimycin A. A comparison with recently described pathways of IFN-mediated transcription factor regulation indicates that the in vitro activation of gamma RF-1 is unique, requiring both membrane and cytosol fractions and inhibition of endogenous tyrosine phosphatase activity.
Collapse
Affiliation(s)
- C A Feghali
- Department of Medicine, University of Pittsburgh School of Medicine, PA 15213, USA
| | | |
Collapse
|