OBJECTIVETo analyze the existence and the dynamic cell frequencies of human cells in goats transplanted in utero with human hematopoietic stem cell (hHSC) by using fluorescence in situ hybridization (FISH) technique.

METHODSInterphase FISH (IFISH) with human-specific 17-chromosome satellite DNA and/or human-specific Y-chromosome satellite DNA as probes was performed to analyze the presence and proportions of human cells in 13 transplanted goats. Samples were peripheral blood cells, bone marrow smears and liver touch imprint preparations.

RESULTSOf the 13 transplanted goats, eleven were identified to present human cells. Among them, two goats transplanted with human male HSC were found to have human male cells. The results demonstrated that these transplanted goats were human/goat HSC xenogeneic chimeras. Human cell frequencies decreased with the goat age (months), but the longest survival reached 21 months. During the detected life periods of goats, human cell frequencies in peripheral blood, bone marrow and liver tissues were less than 1@1000, but local human cell frequencies of 207.92@1000 and 392.41@1000 were detected in the liver tissues of 2 transplanted goats.

CONCLUSIONSThe existence and long-term survival of human cells in transplanted goats detected by FISH indicated that goats were appropriate recipients for hHSC in utero transplantation. The lower human cell frequencies in blood and bone marrow, and the higher local human cell frequencies in liver tissues suggested that the microenvironment of goat liver tissues might favor the survival, proliferation and differentiation of human cells.