Human hepatocytes in mice receiving pre-immune injection with human cord blood cells.

Pharmacology Department, Istituto di Ricerca di Biologia Molecolare "P.Angeletti", Merck Sharp and Dohme Research Laboratories, Rome, Italy.
Biochemical and Biophysical Research Communications (Impact Factor: 2.28). 02/2005; 326(1):66-73. DOI: 10.1016/j.bbrc.2004.10.204
Source: PubMed

ABSTRACT It is well established that certain subpopulations of human adult stem cells can generate hepatocyte-like cells when transplanted into adult immunosuppressed mice. In the present study, we wanted to explore whether xeno-transplantation of human cord blood CD34(+) (hCBCD34(+)) cells during pre-immune stages of development in immunocompetent mice might also lead to human-mouse liver chimerism. Freshly isolated hCBCD34(+) cells were xeno-transplanted into non-immunosuppressed mice by both intra-blastocyst and intra-fetal injections. One and four weeks after birth, immunostaining for different human-specific hepatocyte markers: human hepatocyte-specific antigen, human serum albumin, and human alpha-1-antitrypsin indicated the presence of human hepatocyte-like cells in the livers of transplanted animals. Detection of human albumin mRNA further corroborated the development of pre-immune human-mouse chimeras. The current report, besides providing new evidence of the potential of hCBCD34(+) cells to generate human hepatocyte-like cells, suggests novel strategies for generating immunocompetent mice harboring humanized liver.

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