[Dynamic development of normal fetal circulating blood hematopoietic stem progenitor cell surface antigen in on-going pregnancy].
OBJECTIVE
To investigate the dynamic development of fetal circulating hematopoietic stem/progenitor cell (HSPC) surface antigen CD133, CD34 and CD38 in on-going normal pregnancy.


METHODS
0.2-2.0 ml fetal blood samples were obtained from 106 human fetuses between the gestational age of postmenstrual weeks 12 and 41, 96 being collected by ultrasound-guided percutaneous cordocentesis, 3 by ultrasound-guided selective feticide, and 7 being collected after birth. The nucleated cells (NCs) were separated, and the cell surface antigen CD34, CD38, and CD133 were labeled by bicolor immunofluorescence technique. Fluorescence activated cell sorting (FACS) was performed to analyze the concentration of CD34(+)/NC, CD38(-)/CD34(+), CD133(+)/NC, and CD133(+)/CD34(+) cell respectively.


RESULTS
All operations were uneventful for the fetuses and mothers. The proportions of CD34(+)/NC, CD38(-)/CD34(+)cells, CD133+/NC, and CD133(+)/CD34(+) cells dramatically decreased when the gestational age advanced from week 12 to week 41. CD34+ cell/NC proportion decreased from 4.21% to 0.04% (r(2) = 0.90, x+/- s = 1.54% +/- 0.54%) with the peak at gestational week 12 and a the second peak at the week 20. (2) The percentage of CD38(-)/CD34(+) cells decreased from 58.5% to 10.7% (x+/- s = 28.66% +/- 9.88%) with advancing gestational age (r(2) = 0.82) with the peak at gestational week 12 and a second peak at week 22. (3) The percentage of CD133(+) cells among CD34(+) cells decreased with advancing gestational age, from 87.6% to 48.5% (x+/- s = 63.5% +/- 11.4%). (4) CD133(+) cells/NC concentration decreased with advancing gestational age, from 3.69% to 0.31% (x+/- s = 1.40% +/- 0.86%) with the peak time at gestational week 12., and showed a negative linear correlation with the gestational age (r(2) = 0.76).


CONCLUSIONS
The immunophenotype of normal fetal circulating HSPC changes along with the gestational age in on-going pregnancy. The earlier the time, the more primitive the immunophenotype of the fetal circulating HSPCs. The more primitive fetal circulating HSPCs may be the ideal target for in utero gene therapy.
Zhou
Yi
Y
Fetal Medicine Center, Department of Obstetrics and Gynecology, First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China.
Fang
Qun
Q
Zhuang
Guang-lun
GL
Kong
Qing-Yu
QY
D051997:ADP-ribosyl Cyclase 1 / Q000097:blood*; D000328:Adult; D018952:Antigens, CD34 / Q000097:blood*; D000954:Antigens, Surface / Q000097:blood; D005260:Female; D005312:Fetal Blood / Q000166:cytology*; D047109:Fetal Development; D005865:Gestational Age; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D006801:Humans; D011247:Pregnancy
D018952:Antigens, CD34; D000954:Antigens, Surface; D051997:ADP-ribosyl Cyclase 1