Petri Elo1, Xiang-Guo Li1,2, Heidi Liljenbäck1,3, Maria Gardberg4, Olli Moisio1, Maxwell Miner1, Jenni Virta1, Antti Saraste1,5, Madduri Srinivasarao6, Michael Pugh7, Philip S Low6, Juhani Knuuti1,2,5, Sirpa Jalkanen8, Laura Airas9, Yingjuan June Lu7, Anne Roivainen10,11,12. 1. Turku PET Centre, University of Turku, Turku, Finland. 2. Turku PET Centre, Åbo Akademi University, Turku, Finland. 3. Turku Center for Disease Modeling, University of Turku, Turku, Finland. 4. Department of Pathology, Turku University Hospital and Institute of Biomedicine, University of Turku, Turku, Finland. 5. Turku PET Centre, Turku University Hospital, Turku, Finland. 6. Department of Chemistry, Purdue University, West Lafayette, IN, USA. 7. Endocyte, Inc., now part of Novartis Institutes for Biomedical Research, West Lafayette, IN, USA. 8. MediCity Research Laboratory, University of Turku, Turku, Finland. 9. Department of Neurology, Turku University Hospital, Turku, Finland. 10. Turku PET Centre, University of Turku, Turku, Finland. anne.roivainen@utu.fi. 11. Turku Center for Disease Modeling, University of Turku, Turku, Finland. anne.roivainen@utu.fi. 12. Turku PET Centre, Turku University Hospital, Turku, Finland. anne.roivainen@utu.fi.
Abstract
BACKGROUND: Activated macrophages in the experimental model of multiple sclerosis (MS) express folate receptor-β (FR-β), representing a promising target for the treatment of MS. Here, we both evaluated the efficacy of a novel folate-aminopterin construct (EC2319) in a rat focal model of multiple sclerosis (MS) and investigated the utility of 68Ga-labeled 1,4,7-triazacyclononane-1,4,7-triacetic acid-conjugated folate (68Ga-FOL) for assessing inflammatory lesions. In addition, we investigated whether FR-β is expressed in the brain of patients with MS. METHODS: Focal delayed-type hypersensitivity experimental autoimmune encephalomyelitis (fDTH-EAE) was induced in 40 Lewis rats; 20 healthy Lewis rats were used as controls. Rats were divided into six groups according to the duration of disease (control, acute, or chronic) and intervention (vehicle versus EC2319). 68Ga-FOL analyses, histology, and immunofluorescence of the brain were performed to evaluate the efficacy of subcutaneously administered EC2319 on lesion development. Immunofluorescence was used to assess FR-β expression in postmortem brain samples from 5 patients with MS and 5 healthy controls. RESULTS: Immunofluorescence and histological analyses revealed significant reductions in FR-β expression (P < 0.05) and lesion size (P < 0.01), as well as improved inducible nitric oxide synthase/mannose receptor C type 1 ratios (P < 0.01) in macrophages and microglia during the chronic but not acute phase of fDTH-EAE in EC2319-treated rats. The uptake of IV-injected 68Ga-FOL in the brain was low and did not differ between the groups, but the in vitro binding of 68Ga-FOL was significantly lower in EC2319-treated rats (P < 0.01). FR-β positivity was observed in chronically active lesions and in normal-appearing white matter in MS brain samples. CONCLUSIONS: EC2319 was well tolerated and attenuated inflammation and lesion development in a rat model of a chronic progressive form of MS. Human MS patients have FR-β-positive cells in chronically active plaques, which suggests that these results may have translational relevance.
BACKGROUND: Activated macrophages in the experimental model of multiple sclerosis (MS) express folate receptor-β (FR-β), representing a promising target for the treatment of MS. Here, we both evaluated the efficacy of a novel folate-aminopterin construct (EC2319) in a rat focal model of multiple sclerosis (MS) and investigated the utility of 68Ga-labeled 1,4,7-triazacyclononane-1,4,7-triacetic acid-conjugated folate (68Ga-FOL) for assessing inflammatory lesions. In addition, we investigated whether FR-β is expressed in the brain of patients with MS. METHODS: Focal delayed-type hypersensitivity experimental autoimmune encephalomyelitis (fDTH-EAE) was induced in 40 Lewis rats; 20 healthy Lewis rats were used as controls. Rats were divided into six groups according to the duration of disease (control, acute, or chronic) and intervention (vehicle versus EC2319). 68Ga-FOL analyses, histology, and immunofluorescence of the brain were performed to evaluate the efficacy of subcutaneously administered EC2319 on lesion development. Immunofluorescence was used to assess FR-β expression in postmortem brain samples from 5 patients with MS and 5 healthy controls. RESULTS: Immunofluorescence and histological analyses revealed significant reductions in FR-β expression (P < 0.05) and lesion size (P < 0.01), as well as improved inducible nitric oxide synthase/mannose receptor C type 1 ratios (P < 0.01) in macrophages and microglia during the chronic but not acute phase of fDTH-EAE in EC2319-treated rats. The uptake of IV-injected 68Ga-FOL in the brain was low and did not differ between the groups, but the in vitro binding of 68Ga-FOL was significantly lower in EC2319-treated rats (P < 0.01). FR-β positivity was observed in chronically active lesions and in normal-appearing white matter in MS brain samples. CONCLUSIONS:EC2319 was well tolerated and attenuated inflammation and lesion development in a rat model of a chronic progressive form of MS. Human MS patients have FR-β-positive cells in chronically active plaques, which suggests that these results may have translational relevance.
Authors: Joanna Mikita; Nadège Dubourdieu-Cassagno; Mathilde Sa Deloire; Antoine Vekris; Marc Biran; Gérard Raffard; Bruno Brochet; Marie-Hélène Canron; Jean-Michel Franconi; Claudine Boiziau; Klaus G Petry Journal: Mult Scler Date: 2010-09-02 Impact factor: 6.312
Authors: Yingjuan Lu; Kristin N Wollak; Vicky A Cross; Elaine Westrick; Leroy W Wheeler; Torian W Stinnette; Jeremy F Vaughn; Spencer J Hahn; Le-Cun Xu; Iontcho R Vlahov; Christopher P Leamon Journal: Clin Immunol Date: 2013-10-25 Impact factor: 3.969
Authors: Janine Schniering; Martina Benešová; Matthias Brunner; Stephanie Haller; Susan Cohrs; Thomas Frauenfelder; Bart Vrugt; Carol Feghali-Bostwick; Roger Schibli; Oliver Distler; Cristina Müller; Britta Maurer Journal: Front Immunol Date: 2019-11-22 Impact factor: 7.561
Authors: Yingjuan J Lu; Leroy W Wheeler; Haiyan Chu; Paul J Kleindl; Michael Pugh; Fei You; Satish Rao; Gabriela Garcia; Henry Y Wu; Andre P da Cunha; Richard Johnson; Elaine Westrick; Vicky Cross; Alex Lloyd; Christina Dircksen; Patrick J Klein; Iontcho R Vlahov; Philip S Low; Christopher P Leamon Journal: Cell Rep Med Date: 2021-10-19