title: Phosphatidylserine receptor cooperates with high-density lipoprotein receptor in recognition of apoptotic cells by thymic nurse cells.
abstract: The thymus contains many apoptotic cells that arise from the process of positive and negative selection. Both thymic macrophages and thymic nurse cells/nursing thymic epithelial cells (nursing TECs), non-professional phagocytes, recognize and ingest apoptotic cells without inflammation or tissue damage. Previously we reported that human scavenger receptor class B (SR-B1) is involved in recognition of apoptotic thymocytes by nursing TECs. In this study, we examined the expression and role of a phosphatidylserine receptor (PSR). This receptor is believed to participate in the clearance of apoptotic cells. PSR was strongly expressed in nursing TECs. Transforming growth factor-beta augmented the expression of PSR leading to enhanced binding of apoptotic cells to nursing TECs. In nursing TECs, suppressed expression of human SR-B1 with anti-PSR antibody decreased binding of apoptotic thymocytes to nursing TECs. Our results suggest that both PSR and SR-B1 are expressed in nursing TECs and these receptors appear to play a major role in the clearance of apoptotic cells from the thymus.
authors.affiliation: First Department of Internal Medicine, Kagawa Medical University, Kagawa 761-0793, Japan.
authors.forename: W M
authors.initials: WM
authors.lastname: Cao
authors.forename: K
authors.initials: K
authors.lastname: Murao
authors.forename: H
authors.initials: H
authors.lastname: Imachi
authors.forename: C
authors.initials: C
authors.lastname: Hiramine
authors.forename: H
authors.initials: H
authors.lastname: Abe
authors.forename: X
authors.initials: X
authors.lastname: Yu
authors.forename: H
authors.initials: H
authors.lastname: Dobashi
authors.forename: N C W
authors.initials: NC
authors.lastname: Wong
authors.forename: J
authors.initials: J
authors.lastname: Takahara
authors.forename: T
authors.initials: T
authors.lastname: Ishida
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D006801:Humans; D056484:Jumonji Domain-Containing Histone Demethylases; D008075:Lipoproteins, HDL / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000235:genetics / Q000378:metabolism; D018110:Receptors, Lipoprotein / Q000235:genetics / Q000378:metabolism*; D051116:Receptors, Scavenger; D051122:Scavenger Receptors, Class B; D013950:Thymus Gland / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*
chemical_list: D016207:Cytokines; D008075:Lipoproteins, HDL; D016376:Oligonucleotides, Antisense; C498708:Ptdsr protein, mouse; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; D018110:Receptors, Lipoprotein; D051116:Receptors, Scavenger; C495124:SCARB1 protein, human; D051122:Scavenger Receptors, Class B; C031616:high density lipoprotein receptors; C408123:phosphatidylserine receptor; C498707:JMJD6 protein, human; D056484:Jumonji Domain-Containing Histone Demethylases