[Isolation, proliferation and differentiation of thyroid stem cell from human thyroid nodule tissue].
OBJECTIVE
To explore the presence of a characteristic stem cell population (side population, SP) in human thyroid gland and perform sphere culture method for the isolation and proliferation of thyroid stem cell.


METHODS
Flow cytometry and cell sorting were performed to identify and isolate the ABCG2-positive SP cells from primary thyroid cells. The comparison of gene profiles and morphology between SP and main population (MP) were performed. Primary thyroid cells were also cultured in neurosphere-like growth condition for sphere formation. Gene profile of developed spheres was determined by reverse transcriptase-polymerase chain reaction (RT-PCR) and thyroid lineage commitment was then induced in a differentiating condition. In stem cell-derived thyrocytes, embedded in collagen to form follicles, TSH-dependent (125)iodide uptake was measured.


RESULTS
The SP was identified as a population enriched in stem cells with typical morphology, and characteristics of self-renewal and differentiation. Nonadherent clonal spheres developed in thyroid cell cultures, displaying an expression pattern resembling that of SP cells and in response to TSH and serum these sphere cells differentiated into thyrocytes expressing PAX8, thyroglobulin, sodium iodide symporter, thyroid-stimulating hormone receptor and thyroperoxidase mRNA. And there was TSH-dependent (125)iodide uptake.


CONCLUSIONS
It is shown first time that human thyroid contains an undescribed population of cells with SP phenotype and clonal expansion capacity. Moreover sphere culture method is developed for the isolation and proliferation of thyroid stem cell.
Department of Endocrinology, Beijing Jishuitan Hospital, Fourth Medical College of Peking University, Beijing 100035, China. lanjingling0627@gmail.com
Ling
L
Lan
Dai
D
Cui
Bing-yin
BY
Shi
Guo-ying
GY
Zhang
Wei
W
Deng
Hong
H
Wang
Hai-ling
HL
Chen
Li-li
LL
Deng
D018929:Cell Culture Techniques; D002454:Cell Differentiation; D049109:Cell Proliferation; D002469:Cell Separation; D002478:Cells, Cultured; D006801:Humans; D013234:Stem Cells / Q000166:cytology*; D013961:Thyroid Gland / Q000166:cytology*