Cytoplasmic transfer in the mouse in conjunction with intracytoplasmic sperm injection.
Cytoplasmic transfer (CT) from a donor to a recipient oocyte has been used clinically to facilitate human pregnancies. Data reported here describe the first characterization of CT coincident with intracytoplasmic sperm injection in the mouse system. Sibling oocytes were used to transfer 2, 4, or 6 pl of ooplasm to a recipient egg along with a sperm head using piezo-actuated injection. Survival and fertilization after CT were comparable to controls at 2 pl and 4 pl, but survival was significantly reduced with 6 pl volumes. Development to the blastocyst stage was also inversely related to CT volume, with some decline beginning with the 4 pl CT group. However, some blastocysts did develop in all of the groups. The results are in contrast with human eggs, which tolerate larger CT volumes. Results indicate that the mouse system can be used to characterize the transfer of exogenous materials concomitant with sperm injection, provided that the CT volume is not excessive.
Nagai
Seiichiro
S
Department of Obstetrics and Gynecology, John A. Burns School of Medicine, University of Hawaii, 1319 Punahou Street, Honolulu, Hawaii 96826, USA. naseiichi@hotmail.com
Kasai
Tsuyoshi
T
Hirata
Shuji
S
Hoshi
Kazuhiko
K
Yanagimachi
Ryuzo
R
Huang
Thomas
T
D000818:Animals; D001755:Blastocyst / Q000502:physiology; D002470:Cell Survival; D003593:Cytoplasm; D005314:Embryonic and Fetal Development; D005260:Female; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009865:Oocytes / Q000502:physiology; D013077:Sperm Head; D020554:Sperm Injections, Intracytoplasmic / Q000009:adverse effects