title: Oral delivery of bioencapsulated proteins across blood-brain and blood-retinal barriers.
abstract: Delivering neurotherapeutics to target brain-associated diseases is a major challenge. Therefore, we investigated oral delivery of green fluorescence protein (GFP) or myelin basic protein (MBP) fused with the transmucosal carrier cholera toxin B subunit (CTB), expressed in chloroplasts (bioencapsulated within plant cells) to the brain and retinae of triple transgenic Alzheimer's disease (3×TgAD) mice, across the blood-brain barriers (BBB) and blood-retinal barriers (BRB). Human neuroblastoma cells internalized GFP when incubated with CTB-GFP but not with GFP alone. Oral delivery of CTB-MBP in healthy and 3×TgAD mice shows increased MBP levels in different regions of the brain, crossing intact BBB. Thioflavin S-stained amyloid plaque intensity was reduced up to 60% by CTB-MBP incubation with human AD and 3×TgAD mice brain sections ex vivo. Amyloid loads were reduced in vivo by 70% in hippocampus and cortex brain regions of 3×TgAD mice fed with bioencapsulated CTB-MBP, along with reduction in the ratio of insoluble amyloid β 42 (Aβ42) to soluble fractions. CTB-MBP oral delivery reduced Aβ42 accumulation in retinae and prevented loss of retinal ganglion cells in 3×TgAD mice. Lyophilization of leaves increased CTB-MBP concentration by 17-fold and stabilized it during long-term storage in capsules, facilitating low-cost oral delivery of therapeutic proteins across the BBB and BRB.
authors.affiliation: School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Neha
authors.initials: N
authors.lastname: Kohli
authors.affiliation: School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Donevan R
authors.initials: DR
authors.lastname: Westerveld
authors.affiliation: School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Alexandra C
authors.initials: AC
authors.lastname: Ayache
authors.affiliation: Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA.
authors.forename: Amrisha
authors.initials: A
authors.lastname: Verma
authors.affiliation: Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA.
authors.forename: Pollob
authors.initials: P
authors.lastname: Shil
authors.affiliation: Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA.
authors.forename: Tuhina
authors.initials: T
authors.lastname: Prasad
authors.affiliation: Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Zhu
authors.affiliation: School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Sic L
authors.initials: SL
authors.lastname: Chan
authors.affiliation: Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA.
authors.forename: Qiuhong
authors.initials: Q
authors.lastname: Li
authors.affiliation: School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA. Electronic address: hdaniell@upenn.edu.
authors.forename: Henry
authors.initials: H
authors.lastname: Daniell
mesh_terms: D000284:Administration, Oral; D000544:Alzheimer Disease / Q000188:drug therapy* / Q000473:pathology; D000818:Animals; D001812:Blood-Brain Barrier / Q000378:metabolism*; D001813:Blood-Retinal Barrier / Q000378:metabolism*; D002214:Capsules; D045744:Cell Line, Tumor; D002736:Chloroplasts / Q000378:metabolism*; D002772:Cholera Toxin / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D004676:Myelin Basic Protein / Q000235:genetics / Q000378:metabolism*; D018515:Plant Leaves / Q000166:cytology; D058225:Plaque, Amyloid / Q000188:drug therapy* / Q000473:pathology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D002214:Capsules; D004676:Myelin Basic Protein; D011993:Recombinant Fusion Proteins; D002772:Cholera Toxin