title: A glycosylation-dependent CD45RB epitope defines previously unacknowledged CD27⁻IgM(high) B cell subpopulations enriched in young children and after hematopoietic stem cell transplantation.
abstract: The immune system is dysfunctional for years after hematopoietic stem cell transplantation (HSCT). A potential cause is an intrinsic B cell deficiency. In a cohort of pediatric HSCT patients few CD27(+) B cells formed after transplantation with the number of CD27(+)IgM(high) cells more affected than class-switched ones. A previously unacknowledged population of CD27(-)IgM(high) cells made up the majority of B cells and this population was also enlarged in healthy children compared to adults. Only a minority of these CD27(-)IgM(high) B cells expressed markers typical for transitional B cells, and the non-transitional CD27(-)IgM(high) cells could be further divided into subpopulations based on their ability to extrude the dye Rhodamine 123 and their expression of CD45RB(MEM55), a glycosylation-dependent epitope. Thus, we define several novel human CD27(-)IgM(high) B cell subpopulations in blood, all of which are present in higher frequencies and numbers in young children and after HSCT than in adults.
authors.affiliation: Mucosal Immunobiology and Vaccine Center (MIVAC), Department of Microbiology and Immunology, University of Gothenburg, Gothenburg, Sweden; Department of Clinical Immunology and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden. Electronic address: mats.bemark@immuno.gu.se.
authors.forename: Mats
authors.initials: M
authors.lastname: Bemark
authors.forename: Linda
authors.initials: L
authors.lastname: Friskopp
authors.forename: Shanie
authors.initials: S
authors.lastname: Saghafian-Hedengren
authors.forename: Susanne
authors.initials: S
authors.lastname: Koethe
authors.forename: Anders
authors.initials: A
authors.lastname: Fasth
authors.forename: Jonas
authors.initials: J
authors.lastname: Abrahamsson
authors.forename: Eva
authors.initials: E
authors.lastname: Sverremark-Ekström
authors.forename: Bengt A
authors.initials: BA
authors.lastname: Andersson
authors.forename: Karin
authors.initials: K
authors.lastname: Mellgren
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D016175:B-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D018985:Epitopes, B-Lymphocyte / Q000235:genetics / Q000276:immunology*; D005260:Female; D005456:Fluorescent Dyes; D005786:Gene Expression Regulation; D006031:Glycosylation; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007075:Immunoglobulin M / Q000235:genetics / Q000276:immunology*; D017493:Leukocyte Common Antigens / Q000235:genetics / Q000276:immunology*; D018655:Lymphocyte Count; D008297:Male; D020112:Rhodamine 123; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000172:deficiency / Q000235:genetics / Q000276:immunology*
chemical_list: D018985:Epitopes, B-Lymphocyte; D005456:Fluorescent Dyes; D007075:Immunoglobulin M; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7; D020112:Rhodamine 123; D017493:Leukocyte Common Antigens
keywords: B cell; Hematopoietic stem cell transplantation; Immunological ontogeny; Lymphocyte development