title: Transmaternal cell flow leads to antigen-experienced cord blood.
abstract: Umbilical cord blood (UCB) is used for HSCT. It is known that UCB can comprise Ag-specific T cells. Here we question whether solely transmaternal cell flow may immunize UCB. Twenty-three female UCB samples were collected from healthy mothers and analyzed for minor histocompatibility Ag HY-specific responses. Forty-two of 104 tetramer(pos) T-cell clones, isolated from 16 of 17 UCB samples, showed male-specific lysis in vitro. Male microchimerism was present in 6 of 12 UCB samples analyzed. In conclusion, female UCB comprises HY-specific cytotoxic T cells. The immunization is presumably caused by transmaternal cell flow of male microchimerism present in the mother. The presence of immune cells in UCB that are not directed against maternal foreign Ags is remarkable and may explain the reported clinical observation of improved HSCT outcome with younger sibling donors.
authors.affiliation: Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands. m.p.dierselhuis@lumc.nl
authors.forename: Miranda P
authors.initials: MP
authors.lastname: Dierselhuis
authors.forename: Els C
authors.initials: EC
authors.lastname: Blokland
authors.forename: Jos
authors.initials: J
authors.lastname: Pool
authors.forename: Ellen
authors.initials: E
authors.lastname: Schrama
authors.forename: Sicco A
authors.initials: SA
authors.lastname: Scherjon
authors.forename: Els
authors.initials: E
authors.lastname: Goulmy
mesh_terms: D000954:Antigens, Surface / Q000276:immunology* / Q000378:metabolism; D046528:Chimerism; D005260:Female; D005312:Fetal Blood / Q000166:cytology* / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology; D016130:Immunophenotyping; D008297:Male; D008431:Maternal-Fetal Exchange / Q000276:immunology*; D010298:Parity; D011247:Pregnancy; D035781:Siblings; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000378:metabolism
chemical_list: D000954:Antigens, Surface