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The Insulin-like Growth Factor System and Colorectal Cancer. LIFE (BASEL, SWITZERLAND) 2022; 12:life12081274. [PMID: 36013453 PMCID: PMC9410426 DOI: 10.3390/life12081274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 08/10/2022] [Accepted: 08/12/2022] [Indexed: 11/29/2022]
Abstract
Insulin-like growth factors (IGFs) are peptides which exert mitogenic, endocrine and cytokine activities. Together with their receptors, binding proteins and associated molecules, they participate in numerous pathophysiological processes, including cancer development. Colorectal cancer (CRC) is a disease with high incidence and mortality rates worldwide, whose etiology usually represents a combination of the environmental and genetic factors. IGFs are most often increased in CRC, enabling excessive autocrine/paracrine stimulation of the cell growth. Overexpression or increased activation/accessibility of IGF receptors is a coinciding step which transmits IGF-related signals. A number of molecules and biochemical mechanisms exert modulatory effects shaping the final outcome of the IGF-stimulated processes, frequently leading to neoplastic transformation in the case of irreparable disbalance. The IGF system and related molecules and pathways which participate in the development of CRC are the focus of this review.
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Robajac D, Križáková M, Šunderić M, Miljuš G, Gemeiner P, Nedić O, Katrlík J. Lectin-Based Protein Microarray for the Glycan Analysis of Colorectal Cancer Biomarkers: The Insulin-Like Growth Factor System. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2460:207-222. [PMID: 34972939 DOI: 10.1007/978-1-0716-2148-6_13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Lectin-based protein microarrays are used for glycoprofiling of various kinds of biological samples. Here we describe lectin-based microarray assay in the reverse-phase format where glycoprotein samples are spotted onto microarray slide and then are incubated with set of lectins. This configuration allows high-throughput screening of a large cohort of samples by a set of lectins without need of separation of glycans from glycoproteins. We applied the described method for glycan analysis of glycoprotein biomarkers of colorectal cancer associated with the insulin-like growth factor system.
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Affiliation(s)
- Dragana Robajac
- Institute for the Application of Nuclear Energy (INEP), University of Belgrade, Belgrade, Serbia
| | - Martina Križáková
- Department of Glycobiotechnology, Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Miloš Šunderić
- Institute for the Application of Nuclear Energy (INEP), University of Belgrade, Belgrade, Serbia
| | - Goran Miljuš
- Institute for the Application of Nuclear Energy (INEP), University of Belgrade, Belgrade, Serbia
| | - Peter Gemeiner
- Department of Glycobiotechnology, Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Olgica Nedić
- Institute for the Application of Nuclear Energy (INEP), University of Belgrade, Belgrade, Serbia
| | - Jaroslav Katrlík
- Department of Glycobiotechnology, Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia.
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Jourdi G, Abdoul J, Siguret V, Decleves X, Frezza E, Pailleret C, Gouin-Thibault I, Gandrille S, Neveux N, Samama CM, Pasquali S, Gaussem P. Induced forms of α 2-macroglobulin neutralize heparin and direct oral anticoagulant effects. Int J Biol Macromol 2021; 184:209-217. [PMID: 34126147 DOI: 10.1016/j.ijbiomac.2021.06.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 10/21/2022]
Abstract
Alpha2-macroglobulin (α2M) is a physiological macromolecule that facilitates the clearance of many proteinases, cytokines and growth factors in human. Here, we explored the effect of induced forms of α2M on anticoagulant drugs. Gla-domainless factor Xa (GDFXa) and methylamine (MA)-induced α2M were prepared and characterized by electrophoresis, immunonephelometry, chromogenic, clot waveform and rotational thromboelastometry assays. Samples from healthy volunteers and anticoagulated patients were included. In vivo neutralization of anticoagulants was evaluated in C57Bl/6JRj mouse bleeding-model. Anticoagulant binding sites on induced α2M were depicted by computer-aided energy minimization modeling. GDFXa-induced α2M neutralized dabigatran and heparins in plasma and whole blood. In mice, a single IV dose of GDFXa-induced α2M following anticoagulant administration significantly reduced blood loss and bleeding time. Being far easier to prepare, we investigated the efficacy of MA-induced α2M. It neutralized rivaroxaban, apixaban, dabigatran and heparins in spiked samples in a concentration-dependent manner and in samples from treated patients. Molecular docking analysis evidenced the ability of MA-induced α2M to bind non-covalently these compounds via some deeply buried binding sites. Induced forms of α2M have the potential to neutralize direct oral anticoagulants and heparins, and might be developed as a universal antidote in case of major bleeding or urgent surgery.
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Affiliation(s)
- Georges Jourdi
- Université de Paris, Innovative Therapies in Haemostasis, INSERM UMR_S1140, F-75006, Paris, France; AP-HP. Centre-Université de Paris, Hôpital Cochin, F-75014, Paris, France; Research Centre, Montreal Heart Institute, University of Montreal, Faculty of Pharmacy, Montreal, Canada.
| | - Johan Abdoul
- Université de Paris, Innovative Therapies in Haemostasis, INSERM UMR_S1140, F-75006, Paris, France
| | - Virginie Siguret
- Université de Paris, Innovative Therapies in Haemostasis, INSERM UMR_S1140, F-75006, Paris, France; AP-HP. Nord-Université de Paris, Hôpital Lariboisière, F-75010 Paris, France
| | - Xavier Decleves
- AP-HP. Centre-Université de Paris, Hôpital Cochin, F-75014, Paris, France; Université de Paris, Variabilité de réponse aux psychotropes, INSERM UMR_S1144, F-75006 Paris, France
| | - Elisa Frezza
- Laboratoire CiTCoM, Université de Paris, CNRS, F-75006 Paris, France
| | - Claire Pailleret
- Université de Paris, Innovative Therapies in Haemostasis, INSERM UMR_S1140, F-75006, Paris, France; Clinique du Mont Louis, F-75011 Paris, France
| | - Isabelle Gouin-Thibault
- Laboratoire d'hématologie, CHU Pontchaillou, Université de Rennes 1, CIC-Inserm1414, F-35000 Rennes, France
| | - Sophie Gandrille
- Université de Paris, Innovative Therapies in Haemostasis, INSERM UMR_S1140, F-75006, Paris, France; AP-HP. Centre-Université de Paris, Hôpital Européen Georges Pompidou, F-75015 Paris, France
| | - Nathalie Neveux
- AP-HP. Centre-Université de Paris, Hôpital Cochin, F-75014, Paris, France
| | - Charles Marc Samama
- Université de Paris, Innovative Therapies in Haemostasis, INSERM UMR_S1140, F-75006, Paris, France; AP-HP. Centre-Université de Paris, Hôpital Cochin, F-75014, Paris, France
| | - Samuela Pasquali
- Laboratoire CiTCoM, Université de Paris, CNRS, F-75006 Paris, France
| | - Pascale Gaussem
- Université de Paris, Innovative Therapies in Haemostasis, INSERM UMR_S1140, F-75006, Paris, France; AP-HP. Centre-Université de Paris, Hôpital Européen Georges Pompidou, F-75015 Paris, France.
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Ritsinger V, Brismar K, Mellbin L, Näsman P, Rydén L, Söderberg S, Norhammar A. Elevated levels of insulin-like growth factor-binding protein 1 predict outcome after acute myocardial infarction: A long-term follow-up of the glucose tolerance in patients with acute myocardial infarction (GAMI) cohort. Diab Vasc Dis Res 2018; 15:387-395. [PMID: 29992830 DOI: 10.1177/1479164118781892] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To investigate the long-term prognostic value of insulin-like growth factor-binding protein 1 in patients with acute myocardial infarction. METHODS Patients ( n = 180) with admission glucose < 11 mmol/L without previously known diabetes admitted for an acute myocardial infarction in 1998-2000 were followed for mortality and cardiovascular events (first of cardiovascular mortality/acute myocardial infarction/stroke/severe heart failure) until the end of 2011 (median 11.6 years). Fasting levels of insulin-like growth factor-binding protein 1 at day 2 were related to outcome in Cox proportional hazard regression analyses. RESULTS Median age was 64 years, 69% were male and median insulin-like growth factor-binding protein 1 was 20 µg/L. Total mortality was 34% ( n = 61) and 44% ( n = 80) experienced a cardiovascular event during a median follow-up time of 11.6 years. After age adjustment, insulin-like growth factor-binding protein 1 was associated with all-cause (1.40; 1.02-1.93, p = 0.039) and cancer mortality (2.09; 1.15-3.79, p = 0.015) but not with cardiovascular death ( p = 0.29) or cardiovascular events ( p = 0.57). After adjustments also for previous myocardial infarction, previous heart failure and body mass index, insulin-like growth factor-binding protein 1 was still associated with all-cause mortality (1.38; 1.01-1.89, p = 0.046). CONCLUSION In patients with acute myocardial infarction without previously known diabetes, high insulin-like growth factor-binding protein 1 was associated with long-term all-cause and cancer mortality but not with cardiovascular events.
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Affiliation(s)
- Viveca Ritsinger
- 1 Cardiology Unit, Department of Medicine, Solna, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
- 2 Department of Research and Development, Region Kronoberg, Växjö, Sweden
| | - Kerstin Brismar
- 3 Department of Molecular Medicine and Surgery and Department of Endocrinology, Metabolism and Diabetes, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
| | - Linda Mellbin
- 1 Cardiology Unit, Department of Medicine, Solna, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
| | - Per Näsman
- 4 Centre for Safety Research, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Lars Rydén
- 1 Cardiology Unit, Department of Medicine, Solna, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
| | - Stefan Söderberg
- 5 Division of Cardiology, Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
| | - Anna Norhammar
- 1 Cardiology Unit, Department of Medicine, Solna, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
- 6 Capio St: Görans Hospital, Stockholm, Sweden
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Feng X, Lin J, Xing S, Liu W, Zhang G. Higher IGFBP-1 to IGF-1 serum ratio predicts unfavourable survival in patients with nasopharyngeal carcinoma. BMC Cancer 2017; 17:90. [PMID: 28143425 PMCID: PMC5286734 DOI: 10.1186/s12885-017-3068-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 01/18/2017] [Indexed: 12/20/2022] Open
Abstract
Background The insulin-like growth factor (IGF) system plays an important role in the development and progression of cancer. However, little is known about the expression of the IGF system components and their clinicopathological significance and prognostic value in nasopharyngeal carcinoma (NPC). Methods IGF system components (IGF-1, IGF-2, IGF-1SR, IGFBP-1, IGFBP-2, IGFBP-3, IGFBP-4 and IGFBP-6) were quantified from the plasma of NPC patients and healthy individuals using the RayBio Human Cytokine Antibody Array. IGFBP-1 and IGF-1 mRNA levels were quantified by real-time qPCR, and protein expression was detected by western blot in nine NPC cell lines and four immortalized nasopharyngeal epithelial (NPE) cell lines. Tissue-specific expression of IGFBP-1 and IGF-1 was detected by immunohistochemistry in paraffin-embedded NPC tissues. ELISA analysis was used to measure the serum levels of IGFBP-1 and IGF-1 in 142 NPC patients and 128 healthy controls and determine potential correlation with clinicopathological parameters. Results Significantly higher levels of circulating IGFBP-1 and lower levels of IGF-1 and IGF-2 were detected in NPC patients compared to healthy controls by Cytokine Antibody Array analyses (P = 0.034, 0.012, 0.046, respectively). IGFBP-1 expression was detected in the majority of NPC cell lines, but not in NPE cell lines, and was shown to localize to the nucleus of tumour cells, in contrast to the cytoplasmic staining observed in normal cells. Importantly, IGFBP-1 expression was stronger in NPC tumour tissues compared to peritumoural tissues. In contrast, IGF-1 expression was weak or absent in NPC and NPE cell lines, with the exception of the EBV-infected C666 cell line, and was found to be expressed at lower levels in tumour tissues compared to tumour-adjacent normal tissue. Levels of serum IGFBP-1 were shown to be significantly higher in patients with NPCs compared to healthy control individuals (55.23 ± 41.25 μg/L vs. 32.08 ± 29.73 μg/L, P < 0.001), whereas serum levels of IGF-1 were significantly lower in NPC patients compared to healthy controls (98.14 ± 71.48 μg/L vs. 164.01 ± 92.08 μg/L, P = 0.001). Consistently, the IGFBP-1/IGF-1 serum ratio was shown to be significantly higher in NPC patients compared to healthy control individuals (P = 0.002). Serum levels of IGFBP-1 and the IGFBP-1/IGF-1 ratio significantly correlated with age (P = 0.020; P = 0.016), WHO histological classification (P = 0.044; P = 0.048), titre of EA (EB Virus Capsid Antigen-IgA) and NPC (P = 0.015; P = 0.016). In contrast, higher IGFBP-1 serum levels and IGFBP-1/IGF-1 ratio significantly correlated with poor RFS (P = 0.046; P = 0.037) and OS (P = 0.038; P = 0.009). Multivariate analysis revealed that the IGFBP-1/IGF-1 ratio, but not serum IGFBP-1 level, represents an independent risk factor for poor RFS (P = 0.044) and OS (P = 0.035). Conclusions A higher IGFBP-1/IGF-1 serum ratio is significantly associated with poor prognosis in NPC patients.
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Affiliation(s)
- Xinwei Feng
- Department of Microbial and Biochemical Pharmacy, School of Pharmaceutical Sciences, Sun Yat-sen University, No.132 Waihuandong Road, University Town, Guangzhou, 510006, China
| | - Jianhua Lin
- Department of Clinical Laboratory Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Shan Xing
- Department of Clinical Laboratory Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Wanli Liu
- Department of Clinical Laboratory Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Ge Zhang
- Department of Microbial and Biochemical Pharmacy, School of Pharmaceutical Sciences, Sun Yat-sen University, No.132 Waihuandong Road, University Town, Guangzhou, 510006, China.
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Abstract
α2-macroglobulins are broad-spectrum endopeptidase inhibitors, which have to date been characterised from metazoans (vertebrates and invertebrates) and Gram-negative bacteria. Their structural and biochemical properties reveal two related modes of action: the "Venus flytrap" and the "snap-trap" mechanisms. In both cases, peptidases trigger a massive conformational rearrangement of α2-macroglobulin after cutting in a highly flexible bait region, which results in their entrapment. In some homologs, a second action takes place that involves a highly reactive β-cysteinyl-γ-glutamyl thioester bond, which covalently binds cleaving peptidases and thus contributes to the further stabilization of the enzyme:inhibitor complex. Trapped peptidases are still active, but have restricted access to their substrates due to steric hindrance. In this way, the human α2-macroglobulin homolog regulates proteolysis in complex biological processes, such as nutrition, signalling, and tissue remodelling, but also defends the host organism against attacks by external toxins and other virulence factors during infection and envenomation. In parallel, it participates in several other biological functions by modifying the activity of cytokines and regulating hormones, growth factors, lipid factors and other proteins, which has a great impact on physiology. Likewise, bacterial α2-macroglobulins may participate in defence by protecting cell wall components from attacking peptidases, or in host-pathogen interactions through recognition of host peptidases and/or antimicrobial peptides. α2-macroglobulins are more widespread than initially thought and exert multifunctional roles in both eukaryotes and prokaryotes, therefore, their on-going study is essential.
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Affiliation(s)
- Irene Garcia-Ferrer
- Proteolysis Lab, Structural Biology Unit, "María de Maeztu" Unit of Excellence, Molecular Biology Institute of Barcelona (CSIC), Barcelona Science Park; c/Baldiri Reixac, 15-21, 08028, Barcelona, Spain
- Present address: EMBL Grenoble, 71 Avenue des Martyrs; 38042 CS 90181, Grenoble Cedex 9, France
| | - Aniebrys Marrero
- Proteolysis Lab, Structural Biology Unit, "María de Maeztu" Unit of Excellence, Molecular Biology Institute of Barcelona (CSIC), Barcelona Science Park; c/Baldiri Reixac, 15-21, 08028, Barcelona, Spain
- Present address: Department of Chemistry, University of Zürich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - F Xavier Gomis-Rüth
- Proteolysis Lab, Structural Biology Unit, "María de Maeztu" Unit of Excellence, Molecular Biology Institute of Barcelona (CSIC), Barcelona Science Park; c/Baldiri Reixac, 15-21, 08028, Barcelona, Spain
| | - Theodoros Goulas
- Proteolysis Lab, Structural Biology Unit, "María de Maeztu" Unit of Excellence, Molecular Biology Institute of Barcelona (CSIC), Barcelona Science Park; c/Baldiri Reixac, 15-21, 08028, Barcelona, Spain.
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Lu Y, Chen X, Yin Z, Zhu S, Wu D, Chen X. Screening for potential serum biomarkers in rat mesangial proliferative nephritis. Proteomics 2016; 16:1015-22. [PMID: 26791873 DOI: 10.1002/pmic.201500405] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 12/28/2015] [Accepted: 01/18/2016] [Indexed: 12/13/2022]
Abstract
Mesangial proliferative nephritis (MesPGN) is a common kidney disease worldwide. The main feature of the disease is mesangial cell proliferation-induced injury to kidney function. In this study, we explored serum biomarkers for kidney function injury in anti-Thy1 nephritis. We found that mesangial proliferation were increased on days 5 and 7, and recovered by day 14 in anti-Thy1 nephritis. 24-h urine protein, the ratio of urine protein to urine creatine, serum creatine, and blood urea nitrogen, were increased at days 5 and 7 in the model. We found that TXN, BET1, PrRP, VGF, and NPS differed strongly from controls on days 5 and, associated with kidney injury when detected by SELDI-TOF MS. Moreover, we applied LC-MS to detect differential protein expression and found A2M, C3, ITIH4, ITIH3, VDBP, AFM, and SERPINF2 to be upregulated, and ES1, HPX, SERPINC1, SERPINA1F, SERPINA4, SERPINA3K, SPI, TF, VNN3, SERPINF1, and PON1 to be downregulated, on days 5 and 7, associated with kidney injury. The levels of VNN3 and VDBP were validated by Western blotting. Overall, this study explored a group of candidate biomarkers of mesangial proliferation inducing kidney injury, to provide the basis of an assessment model for MesPGN in the future.
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Affiliation(s)
- Yang Lu
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center of Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing, P. R. China
| | - Xiaoniao Chen
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center of Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing, P. R. China.,Medical College, NanKai University, Tianjin, P. R. China
| | - Zhong Yin
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center of Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing, P. R. China
| | - Shuying Zhu
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center of Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing, P. R. China
| | - Di Wu
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center of Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing, P. R. China
| | - Xiangmei Chen
- Department of Nephrology, Chinese PLA General Hospital, Chinese PLA Institute of Nephrology, State Key Laboratory of Kidney Diseases, National Clinical Research Center of Kidney Diseases, Beijing Key Laboratory of Kidney Disease, Beijing, P. R. China
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Gligorijević N, Nedić O. Interaction between fibrinogen and insulin-like growth factor-binding protein-1 in human plasma under physiological conditions. BIOCHEMISTRY (MOSCOW) 2016; 81:135-40. [DOI: 10.1134/s0006297916020073] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Wyatt AR, Kumita JR, Farrawell NE, Dobson CM, Wilson MR. Alpha-2-Macroglobulin Is Acutely Sensitive to Freezing and Lyophilization: Implications for Structural and Functional Studies. PLoS One 2015; 10:e0130036. [PMID: 26103636 PMCID: PMC4477937 DOI: 10.1371/journal.pone.0130036] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/15/2015] [Indexed: 12/21/2022] Open
Abstract
Alpha-2-macroglobulin is an abundant secreted protein that is of particular interest because of its diverse ligand binding profile and multifunctional nature, which includes roles as a protease inhibitor and as a molecular chaperone. The activities of alpha-2-macroglobulin are typically dependent on whether its conformation is native or transformed (i.e. adopts a more compact conformation after interactions with proteases or small nucleophiles), and are also influenced by dissociation of the native alpha-2-macroglobulin tetramer into stable dimers. Alpha-2-macroglobulin is predominately present as the native tetramer in vivo; once purified from human blood plasma, however, alpha-2-macroglobulin can undergo a number of conformational changes during storage, including transformation, aggregation or dissociation. We demonstrate that, particularly in the presence of sodium chloride or amine containing compounds, freezing and/or lyophilization of alpha-2-macroglobulin induces conformational changes with functional consequences. These conformational changes in alpha-2-macroglobulin are not always detected by standard native polyacrylamide gel electrophoresis, but can be measured using bisANS fluorescence assays. Increased surface hydrophobicity of alpha-2-macroglobulin, as assessed by bisANS fluorescence measurements, is accompanied by (i) reduced trypsin binding activity, (ii) increased chaperone activity, and (iii) increased binding to the surfaces of SH-SY5Y neurons, in part, via lipoprotein receptors. We show that sucrose (but not glycine) effectively protects native alpha-2-macroglobulin from denaturation during freezing and/or lyophilization, thereby providing a reproducible method for the handling and long-term storage of this protein.
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Affiliation(s)
- Amy R. Wyatt
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
- * E-mail:
| | - Janet R. Kumita
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Natalie E. Farrawell
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | | | - Mark R. Wilson
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
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