Engraftment assessment in human and mouse liver tissue after sex-mismatched liver cell transplantation by real-time quantitative PCR for Y chromosome sequences.
Transplanted hepatocytes can engraft, proliferate, and function permanently in host animals. After one cell infusion, however, engrafted hepatocytes constitute only between 1 in 200 to 1 in 3,000 host liver cells. Although transplanted cells can be identified using biochemical and molecular techniques, more accurate methods are needed to evaluate interventions that could improve cell engraftment rates. Real-time polymerase chain reaction (PCR) was done using primers and probes complementary to human testis determining gene (SRY) and mouse testis-specific Y-encoded protein (TSPY) pseudogene. Tissue samples from human or mouse recipients of liver cell transplantation were used to determine the test ability to detect transplanted cell DNA. Real-time PCR for the human SRY and mouse TSPY were species- and sex-specific. These two tests were sensitive in the detection of male DNA. Test sensitivity was consistently found at minimum 1:10,000 of male and female DNA mixing curve in both human SRY and mouse TSPY assays. The optimal amount of sample DNA per reaction to produce the highest sensitivity was 300 ng to 1 microg. Real-time PCR gave similar results whether standard male-female mixtures were prepared from liver cells or mononuclear cells. Engraftment of male liver cells in female liver tissues in mice and humans ranging from 0.125% to 0.257% was successfully measured using this method. Real-time PCR for SRY and TSPY affords a specific, sensitive, and reproducible tool for chimerism analysis in transplanted human and mouse liver tissues. This method could be used to optimize current models of cell transplantation.
Department of Pediatrics, Northwestern University, Children's Memorial Hospital, Children's Memorial Institute for Education and Research, Chicago, IL 60614, USA. lwang509@hotmail.com
Ling-Jia
LJ
Wang
Yong Ming
YM
Chen
David
D
George
Francois
F
Smets
Etienne M
EM
Sokal
Eric G
EG
Bremer
Humberto E
HE
Soriano
D000818:Animals; D018797:Cell Cycle Proteins; D002675:Child, Preschool; D003199:Computer Systems; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D024282:Genes, sry; D022781:Hepatocytes / Q000637:transplantation*; D006650:Histocompatibility Testing; D006801:Humans; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction; D011544:Pseudogenes; D012680:Sensitivity and Specificity; D051876:Sex-Determining Region Y Protein; D013154:Spleen / Q000601:surgery; D014157:Transcription Factors; D018183:Transplantation Chimera; D014998:Y Chromosome / Q000235:genetics*
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C497745:SRY protein, human; D051876:Sex-Determining Region Y Protein; C497746:Sry protein, mouse; C497749:TSPY1 protein, human; D014157:Transcription Factors; D004247:DNA