Calcium ionophore可用於克服ICSI失敗之病患

Calcium ionophore可用於克服ICSI失敗之病患
ICSI前將精蟲預先處理Calcium ionophore，可去除精蟲之頂體acrosome，造成ICSI後經蟲染色體重塑較為同步化


http://www.biolreprod.org/content/75/3/442.full

Sperm Chromatin Remodeling after Intracytoplasmic Sperm Injection Differs from That of In Vitro Fertilization1

1. Anna Ajduk ^4 5 , 
2. Yasuhiro Yamauchi ⁴ and 
3. Monika A Ward2,3, ⁴

+Author Affiliations

1. Institute for Biogenesis Research,⁴ John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii 96822
2. Department of Embryology,⁵ Institute of Zoology, Warsaw University, 02–096 Warsaw, Poland

Next Section

Abstract

Intracytoplasmic sperm injection (ICSI) is a popular method used in assisted conception, and live offspring have been born from a variety of species, including humans. In ICSI, sperm chromatin is introduced into the oocyte together with the acrosome, a structure that does not enter the oocyte during normal fertilization. We compared sperm chromatin remodeling, the potential of embryos to develop in vitro, and DNA synthesis in mouse embryos obtained from in vitro fertilization (IVF) and ICSI. We also tested whether sperm pretreatment prior to ICSI (i.e., capacitation, acrosome reaction, membrane removal, and reduction of disulfide bonds in protamines) facilitates chromatin remodeling and affects embryo development. Sperm chromatin was examined on air-dried, Giemsa-stained preparations at 30-min intervals for up to 4.5 h postfertilization. In all experimental groups, the oocytes underwent activation and formed pronuclei with similar rates. However, the dynamics of sperm chromatin remodeling in ICSI and IVF embryos varied. In ICSI, chromatin remodeling was more asynchronous than in IVF. Sperm capacitation prior to injection enhanced remodeling asynchrony and resulted in delayed pronuclei formation and DNA synthesis. The removal of the acrosome prior to injection with calcium ionophore A23187 but not with detergent Triton X-100 allowed more synchronous chromatin remodeling, timely DNA synthesis, and good embryo development. Our data have significance for the refinement of the molecular and biologic mechanisms associated with ICSI for current and future applications.