{"entity": "journal", "iuid": "2f1270d54b7d4751833da480f115300a", "timestamp": "2026-08-20T20:27:26.982Z", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/journal/EJNMMI%20Radiopharm%20Chem.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/journal/EJNMMI%20Radiopharm%20Chem"}}, "title": "EJNMMI Radiopharm Chem", "issn": "2365-421X", "issn-l": null, "publications_count": 4, "publications": [{"entity": "publication", "iuid": "322314b2ecc94d8a871afeaa786aee16", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/322314b2ecc94d8a871afeaa786aee16.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/322314b2ecc94d8a871afeaa786aee16"}}, "title": "PDGFR\u00df targeted positron emission tomography as a non-invasive biomarker for activated hepatic stellate cells: lasts steps before clinical translation.", "authors": [{"family": "Yashaswini", "given": "Chittampalli N", "initials": "CN"}, {"family": "Mitran", "given": "Bogdan", "initials": "B"}, {"family": "Papadopoulos", "given": "Natalia", "initials": "N"}, {"family": "Wegrzyniak", "given": "Olivia", "initials": "O"}, {"family": "L\u00f6fblom", "given": "John", "initials": "J"}, {"family": "Nordstr\u00f6m", "given": "Helena", "initials": "H"}, {"family": "Velikyan", "given": "Irina", "initials": "I"}, {"family": "Abouzayed", "given": "Ayman", "initials": "A"}, {"family": "Johansson", "given": "Lars", "initials": "L"}, {"family": "Hagmar", "given": "Per", "initials": "P"}, {"family": "Wagner", "given": "Michael", "initials": "M"}, {"family": "Frejd", "given": "Fredrik Y", "initials": "FY"}, {"family": "Korsgren", "given": "Olle", "initials": "O"}, {"family": "Heldin", "given": "Carl-Henrik", "initials": "CH"}, {"family": "Friedman", "given": "Scott L", "initials": "SL"}, {"family": "Eriksson", "given": "Olof", "initials": "O", "orcid": "0000-0002-2515-8790", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/85991bf00e4b4a26ab15599d25c58601.json"}}], "type": "journal article", "published": "2025-12-13", "journal": {"title": "EJNMMI Radiopharm Chem", "issn": "2365-421X", "volume": "10", "issue": "1", "pages": "80", "issn-l": null}, "abstract": "BACKGROUND: Activated hepatic stellate cells (aHSCs) are the key cell population in the injured liver driving fibrogenesis. aHSCs express platelet-derived growth factor receptor beta (PDGFR\u00df), which is absent from quiescent HSCs. PDGFR\u00df is therefore an attractive target of PET tracers for imaging of fibrogenesis. Here, we present the pharmacological characterization of [68Ga]Ga-DOTA-Cys-ATH001 in preparation for clinical translation and further confirm PDGFR\u00df as a biomarker of activated HSCs in liver disease by single cell sequencing. METHODS: The expression of PDGFR\u00df in subpopulations of HSCs was evaluated in scRNAseq datasets from both a mouse and human liver samples. DOTA-Cys-ATH001 was evaluated for affinity and mechanism of binding to PDGFR\u00df. [68Ga]Ga-DOTA-Cys-ATH001 was evaluated for binding in vitro in mouse and human liver biopsies. The in vivo stability, biodistribution, pharmacokinetics, dosimetry and microdosing toxicology were evaluated in rats and pigs. RESULTS: PDGFR\u00df expression was specifically upregulated in activated HSCs. [68Ga]Ga-DOTA-Cys-ATH001 could differentiate fibrotic liver from healthy liver. The binding co-localized with tissue areas positive for collagen deposition and PDGFR\u00df immunostaining. Based on the microdosing toxicology study the no observed adverse effect level was at least 1000 \u00b5g/kg, suggesting that the intended clinical PET scan dose is safe for use. Dosimetry calculations of [68Ga]Ga-DOTA-Cys-ATH001 predicted an effective dose in human amenable to repeated examinations. CONCLUSIONS: The data presented here suggests that PDGFR\u03b2 PET imaging with [68Ga]Ga-DOTA-Cys-ATH001 has potential for non-invasive detection of activated HSCs. Clinical translation of [68Ga]Ga-DOTA-Cys-ATH001 is ongoing.", "doi": "10.1186/s41181-025-00410-2", "pmid": "41389114", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC12711615"}, {"db": "pii", "key": "10.1186/s41181-025-00410-2"}], "notes": [], "created": "2026-08-20T12:37:23.285Z", "modified": "2026-08-20T12:37:23.377Z"}, {"entity": "publication", "iuid": "36b91cc1d78942b99ead3dbcaec0e49a", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/36b91cc1d78942b99ead3dbcaec0e49a.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/36b91cc1d78942b99ead3dbcaec0e49a"}}, "title": "Extending the shelf life of \u2076\u2078Ge/\u2076\u2078Ga generators via preconcentration of [\u2076\u2078Ga]GaCl\u2083 for preclinical application.", "authors": [{"family": "Mallapura", "given": "Hemantha", "initials": "H", "orcid": "0000-0002-7325-4314", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/4d8d3338d3064f1f8e69afb4c33bc749.json"}}, {"family": "Eriksson", "given": "Olof", "initials": "O"}], "type": "journal article", "published": "2025-11-26", "journal": {"title": "EJNMMI Radiopharm Chem", "issn": "2365-421X", "volume": "10", "issue": "1", "pages": "76", "issn-l": null}, "abstract": "\u2076\u2078Ga-labeled tracers are increasingly important for PET imaging and as companion diagnostics with new therapeutic radiopharmaceuticals. The \u2076\u2078Ge/\u2076\u2078Ga generator is a common source for clinical and preclinical \u2076\u2078Ga-tracer production; however, its shelf life and efficiency are critical because of the high cost of generator replacement. This study assessed whether preconcentration of [\u2076\u2078Ga]GaCl\u2083 using strong cation exchange (SCX) resin can increase yield, apparent molar activity (AMA) and also extend generator shelf-life for preclinical applications.\n\nA \u2076\u2078Ge/\u2076\u2078Ga generator (1.8 GBq at purchase, 14-18 months old) was used. Direct elution involved elution of [\u2076\u2078Ga]GaCl\u2083 in 0.1 M HCl, followed by addition to a DOTA-conjugated affibody in acetate buffer (pH 4.6). Preconcentration involved trapping [\u2076\u2078Ga]GaCl\u2083 on a SCX (Chromafix PS-H\u207a) cartridge, rinsing, and eluting with 0.12 M HCl in 5 M NaCl (300-500 \u00b5L), followed by radiolabeling. Radiolabeling was performed at 75-80 \u00b0C for 15 min, the products were purified using a NAP-5 column, and the purity was assessed by high-performance liquid chromatography (HPLC). The SCX cartridge trapping efficiency was > 99%, with a elution efficiency of 95.2 \u00b1 1.2% (n = 8). For direct elution, the decay-corrected radiochemical yield (RCYdc) was 78.7 \u00b1 1.5% (n = 3), the AMA was 5.6 \u00b1 0.4 MBq/nmol, and the radiochemical purity (RCP) was 95.3 \u00b1 0.6%. For preconcentration, RCYdc was 69.0 \u00b1 10.0% (n = 3), AMA was 12.6 \u00b1 2.1 MBq/nmol, and RCP was 95.7 \u00b1 3.0%.\n\nThe preconcentration technique doubled the product yield and AMA, and extended the shelf life of the generator by 9-12 months for preclinical applications. Preconcentration of [\u2076\u2078Ga]GaCl\u2083 using SCX resin is a robust, cost-effective method for maximizing \u2076\u2078Ga recovery and increasing the radiotracer yield and AMA, especially with older generators. This approach extends generator shelf-life, supports sustained preclinical research, and reduces radioactive waste and operational costs.", "doi": "10.1186/s41181-025-00406-y", "pmid": "41296135", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC12669415"}, {"db": "pii", "key": "10.1186/s41181-025-00406-y"}], "notes": [], "created": "2026-08-20T12:37:21.428Z", "modified": "2026-08-20T12:37:21.528Z"}, {"entity": "publication", "iuid": "e848e0a9d91c4edd8a568b2048248210", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/e848e0a9d91c4edd8a568b2048248210.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/e848e0a9d91c4edd8a568b2048248210"}}, "title": "PET imaging of platelet derived growth factor receptor \u03b2 in lung fibrosis.", "authors": [{"family": "Wegrzyniak", "given": "Olivia", "initials": "O", "orcid": "0000-0001-9636-0390", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/627311bb7c9f4d2e904eb3a6a62198bd.json"}}, {"family": "Lechi", "given": "Francesco", "initials": "F"}, {"family": "Rokka", "given": "Johanna", "initials": "J"}, {"family": "Mitran", "given": "Bogdan", "initials": "B"}, {"family": "Zhang", "given": "Bo", "initials": "B"}, {"family": "Thelander", "given": "Ulrika", "initials": "U"}, {"family": "L\u00f6fblom", "given": "John", "initials": "J"}, {"family": "Frejd", "given": "Fredrik Y", "initials": "FY"}, {"family": "Korsgren", "given": "Olle", "initials": "O"}, {"family": "Perchiazzi", "given": "Gaetano", "initials": "G"}, {"family": "Eriksson", "given": "Jonas", "initials": "J"}, {"family": "Eriksson", "given": "Olof", "initials": "O"}], "type": "journal article", "published": "2025-07-15", "journal": {"title": "EJNMMI Radiopharm Chem", "issn": "2365-421X", "volume": "10", "issue": "1", "pages": "44", "issn-l": null}, "abstract": "Lung diseases such as idiopathic pulmonary fibrosis and acute respiratory distress syndrome (ARDS) are associated with significant morbidity and mortality, with limited treatment options. Platelet-derived growth factor receptor beta (PDGFR\u03b2) signaling pathway is a key driver of fibrogenesis in different organs. In the lungs, pericytes have a high PDGFR\u03b2 expression, and their role as immune regulators and progenitors of myofibroblasts is increasingly recognized. Non-invasive techniques to assess active lung tissue remodeling are needed to improve disease monitoring and treatment evaluation. This study aimed to evaluate [18F]TZ-Z09591, targeting PDGFR\u03b2, for imaging pulmonary injuries in human biopsies, and in vivo in animal models of lung injury.\n\n[18F]TZ-Z09591 demonstrated high and specific binding to PDGFR\u03b2-expressing cells. Autoradiography confirmed tracer uptake in lung injuries, including fibrotic foci, from human, rat, and pig lung tissues. In vivo positron emission tomography (PET) imaging of bleomycin-induced lung fibrosis in rats and an ARDS pig model showed significantly increased uptake in diseased lung segments compared to controls, especially in pulmonary injuries with collagen deposition, despite moderate background uptake.\n\nThis study demonstrated that [18F]TZ-Z09591 can assess PDGFR\u03b2 expression in pulmonary injuries, supporting its potential for non-invasive assessment of lung tissue remodeling. PET imaging targeting PDGFR\u03b2 could improve disease monitoring, and provide new insights into pulmonary fibrosis progression.", "doi": "10.1186/s41181-025-00366-3", "pmid": "40664934", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC12263540"}, {"db": "pii", "key": "10.1186/s41181-025-00366-3"}], "notes": [], "created": "2026-08-20T12:37:19.183Z", "modified": "2026-08-20T12:37:19.261Z"}, {"entity": "publication", "iuid": "5367fa0ce71446ffbb8c0cc2f5042de5", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/5367fa0ce71446ffbb8c0cc2f5042de5.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/5367fa0ce71446ffbb8c0cc2f5042de5"}}, "title": "Optimized method for fluorine-18 radiolabeling of Affibody molecules using RESCA.", "authors": [{"family": "Lechi", "given": "Francesco", "initials": "F"}, {"family": "Eriksson", "given": "Jonas", "initials": "J"}, {"family": "Odell", "given": "Luke R", "initials": "LR"}, {"family": "Wegrzyniak", "given": "Olivia", "initials": "O"}, {"family": "L\u00f6fblom", "given": "John", "initials": "J"}, {"family": "Frejd", "given": "Fredrik Y", "initials": "FY"}, {"family": "Zhang", "given": "Bo", "initials": "B"}, {"family": "Eriksson", "given": "Olof", "initials": "O", "orcid": "0000-0002-2515-8790", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/85991bf00e4b4a26ab15599d25c58601.json"}}], "type": "journal article", "published": "2024-10-26", "journal": {"title": "EJNMMI Radiopharm Chem", "issn": "2365-421X", "volume": "9", "issue": "1", "pages": "73", "issn-l": null}, "abstract": "In recent years, the interest in Al[18F]F as a labeling agent for Positron Emission Tomography (PET) radiotracers has risen, as it allows for fast and efficient fluorine-18 labeling by harnessing chelation chemistry. The introduction of Restrained Complexing Agent (RESCA) as a chelator has also shown that chelator-based radiolabeling reactions can be performed in mild conditions, making the radiolabeling process attractively more facile than most conventional radiofluorination methods. The aim of the study was to establish optimized conditions for Al[18F]F labeling of Affibody molecules using RESCA as a complexing agent, using Z09591 and Z0185, two Affibody proteins targeting PDGFR\u03b2 and TNF\u03b1, respectively, as model compounds.\n\nThe Al[18F]F labeling of RESCA-conjugated Z09591 was tested at different temperatures (rt to 60 \u00b0C) and with varying reaction times (12 to 60 min), and optimal conditions were then implemented on RESCA-Z0185. The optimized synthesis method was: 1.5-2.5 GBq of cyclotron produced fluorine-18 were trapped on a QMA cartridge and eluted with saline solution to react with 12 nmol of AlCl3 and form Al[18F]F. The respective RESCA-conjugated Affibody molecule (14 nmol) in NaOAc solution was added to the Al[18F]F solution and left to react at 60 \u00b0C for 12 min. The mixture was purified on a NAP5 size exclusion column and then analyzed by HPLC. The entire process took approximately 35 min, was highly reproducible, indicating the efficiency and reliability of the method. The labeled compounds demonstrated retained biological function for their respective targets after purification.\n\nWe present a general and optimized method for Al[18F]F labeling of RESCA-conjugated Affibody molecules, which can be widely applied to this class of peptide-based imaging agents. Moreover, radiochemical yields were improved when the labeling was conducted at 37 \u00b0C or above. In vitro and in vivo assessment of the respective tracers was promising, showing retained binding capacity as well as moderate defluorination, which is usually regarded as a potential downside for RESCA-conjugated tracers.", "doi": "10.1186/s41181-024-00304-9", "pmid": "39460878", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC11512968"}, {"db": "pii", "key": "10.1186/s41181-024-00304-9"}], "notes": [], "created": "2026-08-20T12:37:17.275Z", "modified": "2026-08-20T12:37:17.369Z"}], "created": "2026-08-20T12:37:17.328Z", "modified": "2026-08-20T12:37:17.328Z"}