2100 OET ASSAY OF NON-MOTILE SPERM TO PREDICT TWO-CELL EMBRYO AND LIVE-BIRTH RATES USING A MOUSE ICSI MODEL

Abstract

You have accessJournal of UrologyInfertility: Physiology, Pathophysiology, Basic Research1 Apr 20122100 OET ASSAY OF NON-MOTILE SPERM TO PREDICT TWO-CELL EMBRYO AND LIVE-BIRTH RATES USING A MOUSE ICSI MODEL Maurice Garcia, Aaron Ohta, Ryuzo Yanagimachi, W. Steve Ward, Stefan Moisyadi, and Joel Marh Maurice GarciaMaurice Garcia San Francisco, CA More articles by this author , Aaron OhtaAaron Ohta Honolulu, HI More articles by this author , Ryuzo YanagimachiRyuzo Yanagimachi Honolulu, HI More articles by this author , W. Steve WardW. Steve Ward Honolulu, HI More articles by this author , Stefan MoisyadiStefan Moisyadi Honolulu, HI More articles by this author , and Joel MarhJoel Marh Honolulu, HI More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.2267AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Optoelectronic Tweezers (OET) is a non-invasive motility-independent assay that employs weak AC fields and light to assess a cell's dielectric potential. We have shown that living cells display a strong attraction (+) response to an OET field, whereas dead cells are weakly repulsed (−) or are neutral (do not respond) to OET. We have previously reported how sperm can be assayed with OET to predict sperm viability in vitro. Using a mouse ICSI model, we sought to assess whether OET assay lowers pup rates, and, whether it predicts ICSI outcomes among non-motile sperm, comparing (presumably healthy) and sperm damaged by freeze-thaw in a dose-dependent fashion. METHODS Sperm from healthy B6D2F1 mice was harvested and suspended in CZB (highly electrically conductive). Sperm were randomized to 3 experimental groups suspended in Mannitol Electrofusion Medium (MEM) (OET compatible because minimally conductive): Group 1 (no treatment), Group 2 (Freeze-Thaw in MEM x 1). After treatment, random samples of only non-motile sperm underwent OET assay, followed by ICSI and embryo transfer. Positive and negative assay and experimental control groups were also included. (See Table). ICSI survival, %-Fertilization, %-2PN rates, and pup-rates following embryo transfer were assessed. Mixed regression modeling was applied to assess differences among groups. RESULTS Non-motile sperm had the following mean OET assay responses (Maximum OET induced velocity; += attraction, −= repulsion): +2.5μm/sec (SD 2.6) (untreated group), − 0.15μm/sec (SD .08) (freeze-thaw x1 group), and 0μm/sec (0.21). ICSI outcomes: (see Table). All pups were live-born and healthy appearing. CONCLUSIONS We demonstrate that it is feasible to use OET to assay non-motile sperm for ICSI using an in vivo mouse model. Our results also show that non-motile (vs. motile) sperm have equal 2-cell rates, but significantly lower live birth rate, even in optimized medium. OET assay discriminated among all 3 sperm groups, and predicted a significantly greater 2-cell embryo rate among sperm not exposed to the harmful effects of freeze-thaw. While a trend suggests that OET response predicts live birth rates, the study was underpowered due to the clustered nature (i.e. recipients) of embryo transfer data. To definitively assess potential harm and ability to predict live birth-rates, future studies should include an equal number of embryos transferred and a greater number of recipients, and, should seek to optimize OET media. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e846-e847 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Maurice Garcia San Francisco, CA More articles by this author Aaron Ohta Honolulu, HI More articles by this author Ryuzo Yanagimachi Honolulu, HI More articles by this author W. Steve Ward Honolulu, HI More articles by this author Stefan Moisyadi Honolulu, HI More articles by this author Joel Marh Honolulu, HI More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...