title: Maternal and fetal microchimerism in granulocytes.
abstract: Cell trafficking during pregnancy may result in durable microchimerism, both fetal microchimerism in the mother and maternal microchimerism in her children. Whether microchimerism is continuously replenished has not been well-described. To address this question, we isolated granulocytes, cells with relatively short half-lives, from peripheral blood of healthy women. CD66b-positive cells were isolated by fluorescence activated cell sorting and a panel of polymorphism-specific quantitative pCR assays was employed to investigate fetal and maternal microchimerism. Overall 33% (10/30) of study subjects had at least one source of microchimerism in CD66b(+) cells. Interestingly, maternal microchimerism was more common than fetal microchimerism, 40% vs. 15%, respectively (p = 0.05) and was present at higher levels (p = 0.03). The identification of maternal and fetal origin CD66b(+) cells is strong evidence for an active microchimeric hematopoietic stem and progenitor cell niche. Furthermore, microchimeric CD66b(+) cells could have an impact on innate and adaptive immune responses.
authors.affiliation: Clinical Research Division; Fred Hutchinson Cancer Research Center.
authors.forename: Chennakesava Cuddapah
authors.initials: CC
authors.lastname: Sunku
authors.forename: Vijayakrishna K
authors.initials: VK
authors.lastname: Gadi
authors.forename: Berengere
authors.initials: B
authors.lastname: de Laval de Lacoste
authors.forename: Katherine A
authors.initials: KA
authors.lastname: Guthrie
authors.forename: J Lee
authors.initials: JL
authors.lastname: Nelson