Successful multilineage engraftment of human cord blood cells in pigs after in utero transplantation.
BACKGROUND
Successful engraftment of human hematopoietic stem and progenitor cells (HSPCs) in a large animal may serve not only as a model to study human hematopoiesis but also as a bioreactor to expand human HSPCs in vivo. The aim of this study was to accomplish xenotransplantation of human HSPCs into pig.


METHODS
Total mononuclear or CD34-positive HSPCs obtained from human cord blood were xenotransplanted percutaneously under an ultrasonographic guidance into preimmune pig fetuses. Peripheral blood and bone marrow (BM) cells of recipient pigs were collected and analyzed for the presence of human cells by a polymerase chain reaction to detect human specific Alu sequence on DNA extracted from those cells. Fluorescence-activated cell sorting (FACS) analysis was also performed to detect human hematopoietic cells.


RESULTS
Transplantation of human cord blood cells into pig fetuses aged less than 52 days postcoitus resulted in a good engraftment rate. In one case, engraftment was detected up to 315 days posttransplantation by polymerase chain reaction. Human hematopoietic cells were detectable also by FACS in peripheral blood and BM. Furthermore, human CD34+ HSPCs were also observed in the BM of recipients. Those CD34+ cells in BM were sorted by FACS and subjected to further analyses. First, in vitro colony formation assay resulted in formations of multilineage colonies. Second, when they were transplanted into an immunodeficient mouse they were engrafted in the mouse.


CONCLUSIONS
These data indicate an engraftment of human HSPCs in pig BM. In utero transplantation of human HSPCs into a preimmune pig fetus is useful to establish a pig reproducing human hematopoiesis.
Fujiki
Yutaka
Y
Department of Immunology, Institute of Basic Medical Sciences and Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Japan.
Fukawa
Kazuo
K
Kameyama
Kenji
K
Kudo
Osamu
O
Onodera
Masafumi
M
Nakamura
Yukio
Y
Yagami
Ken-ichi
K
Shiina
Yoshihiro
Y
Hamada
Hiromi
H
Shibuya
Akira
A
Nakauchi
Hiromitsu
H
D000818:Animals; D001853:Bone Marrow / Q000196:embryology; D002460:Cell Line; D004247:DNA / Q000032:analysis; D005312:Fetal Blood / Q000166:cytology*; D005333:Fetus / Q000737:chemistry / Q000601:surgery*; D005434:Flow Cytometry; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D033581:Stem Cell Transplantation; D013552:Swine; D014183:Transplantation, Heterologous
D004247:DNA