Cell Injection Services

Introduction

The ES cell injection service includes:
Production or purchase of superovulated or hyperovulated and mated blastocyst donors.
Generation of pseudopregnant foster mothers by mating outbred ICR females with vasectomized males and checking for vaginal plugs the next day.
Injection of as many expanded blastocysts as possible with between 12-15 ES cells each.
Transfer of injected blastocysts to the uterine horns of 2.5 dpc foster mothers, or to the oviducts of 0.5 dpc foster mothers (dpc = days post-coitus).
Monitoring of foster mothers before and after birth of pups.
identification of chimeric pups by coat color and determination of sex (in cases where chimeras cannot be identified by coat color, the TMF will genotype offspring by PCR for a neo cassette or other suitable marker).
Transfer of chimeric pups to client after weaning.

Summary

Injection of embryonic stem cells into mouse blastocysts results in chimeric mice, in which some cells in each tissue are derived from the ES cell lineage. If the ES cells have been genetically modified, e.g., via gene targeting, those modifications can be passed on to offspring from the chimeras. Since ES cells are usually heterozygous for the genetic modification, roughly half of the offspring arising from the ES cell lineage will carry the modification. Similar to DNA microinjection to produce transgenic mice, our ES cell injection service involves the superovulation or hyperovulation and mating of blastocyst donors to obtain large numbers of embryos, and injected embryos are implanted into pseudopregnant foster mothers.

Turnaround Times

The minimum time required to produce chimeric mice that can be transferred to the client is about 8 weeks, once we have ES cells ready for injection and the necessary paperwork. This includes about 2 weeks to order the blastocyst donors, 3 weeks gestation time, and 3 weeks from birth to weaning.

The turnaround time can be much longer, either because of previously scheduled orders or because of a failure to produce chimeras from the first injection. However, if no chimeras are produced the first time and the total pup yield is reasonably normal, repeating the injection with the same clone is unlikely to be successful.

CD Genomics has already updated its technology platforms to mainstream NGS, long-read sequencing, and microarray instruments. We continue to strive to offer the same reliable services to pharmaceutical and biotechnology companies, as well as academia and government agencies, for all your sequencing or array needs.