What contributes to the success of in vitro fertilization using cryopreserved spermatozoa in rodents?

Junya Ito

doi:10.4172/2165-7491.1000e102

Abstract

In 1963, Yanagimachi and Chang first succeeded in fertilizing golden hamster eggs in vitro without any contributions from the female genital tract [1]. This is the first success of 'In Vitro Fertilization (IVF)' in mammals. After this success, the protocol of IVF has been established in most of mammalian species studied up to date. At last, the Nobel Prize in Physiology or Medicine 2010 was awarded to Dr. Robert G. Edwards who reported the first success of IVF in human with Dr. Patrick C. Steptoe [2]. Also in experimental animals, IVF is a powerful tool for production of offspring. Alternatively, intracytoplasmic sperm injection (ICSI) is now available for the purpose; however, ICSI requires a great deal of skill and cannot be used for many oocytes at the same time. Thus, especially in the production of rodent offspring at the facility, IVF is a more simple and general-purpose method. Moreover using frozen-thawed spermatozoa for IVF can decrease the number of males to be sacrificed for collection of epididymal spermatozoa. However, it has been reported that frozen-thawed spermatozoa from several strains even in mice contribute to low fertility after IVF. Since fresh sperm can fertilize to the oocytes, the process during freezing and thawing seems to affect serious damage of the sperm. Recently, some recent reports have demonstrated significant improvement of IVF using cryopreserved sperm.

Highlights

Even though transgenic mouse models have been widely used as disease models in biomedical research, organs size, genetic and physiological differences between human and rodents have put limitations on applying the rodents study to the human [1,2]
Those who interested in obtaining canine clones and expect a perfect phenotypic copy should be made aware of the diversity of phenotypes that may occur in animals obtained from donor cells with the same genotype
In canine Somatic Cell Nuclear Transfer (SCNT), cloned dogs were generated by nuclear transfer using Canine Adipose-Derived Mesenchymal Stem Cells (cASCs) [32], these outcomes suggest that cASCs could be a useful tool as nuclear donor cells for SCNT as well as clinical applications

Summary

Introduction

Even though transgenic mouse models have been widely used as disease models in biomedical research, organs size, genetic and physiological differences between human and rodents have put limitations on applying the rodents study to the human [1,2]. Recent successes in creating transgenic animals [14,15,16,17,18,19] using Somatic Cell Nuclear Transfer (SCNT) technique which targeted modification of the genome of the donor cells gave promise to future generation of genetically modified models in large animal including dogs [20,21]. The transgenic cloned animals of having identical genomic background are extremely valuable for biomedical research, in which the transgenic SCNT technique is worth enough Those who interested in obtaining canine clones and expect a perfect phenotypic copy should be made aware of the diversity of phenotypes that may occur in animals obtained from donor cells with the same genotype. In canine SCNT, cloned dogs were generated by nuclear transfer using cASC [32], these outcomes suggest that cASCs could be a useful tool as nuclear donor cells for SCNT as well as clinical applications

Current progress in generating disease model dog

Conclusion