PubMed Health⌕ Search

Biomedical subjects

Christine Mather-Love

Publications and source records attributed to Christine Mather-Love.

3 recordsLinked to original sources

Germline transmission of genetically modified primordial germ cells.

Primordial germ cells (PGCs) are the precursors of sperm and eggs. In most animals, segregation of the germ line from the somatic lineages is one of the earliest events in development; in avian embryos, PGCs are first identified in an extra-embryonic region, the germinal crescent, after approximately 18 h of incubation. After 50-55 h of development, PGCs migrate to the gonad and subsequently produce functional sperm and oocytes. So far, cultures of PGCs that remain restricted to the germ line have not been reported in any species. Here we show that chicken PGCs can be isolated, cultured and genetically modified while maintaining their commitment to the germ line. Furthermore, we show that chicken PGCs can be induced in vitro to differentiate into embryonic germ cells that contribute to somatic tissues. Retention of the commitment of PGCs to the germ line after extended periods in culture and after genetic modification combined with their capacity to acquire somatic competence in vitro provides a new model for developmental biology. The utility of the model is enhanced by the accessibility of the avian embryo, which facilitates access to the earliest stages of development and supplies a facile route for the reintroduction of PGCs into the embryonic vasculature. In addition, these attributes create new opportunities to manipulate the genome of chickens for agricultural and pharmaceutical applications.

Animals↗

Avian embryonic stem cells.

Blastodermal cells derived from the area pellucida of a stage X (EG&K) embryo have the potential to contribute to the somatic tissues and the germ line when reintroduced into a stage X (EG&K) recipient embryo. This chapter describes a method to culture chicken embryonic stem (cES) cells derived from blastodermal cells. Within the first week of culture, the cells change their morphology; they become smaller with a large nucleus and a prominent nucleolus. The cES cells remain chromosomally normal and can be cultured for extended periods. They can be modified genetically using standard electroporation procedures and, after injection into a recipient embryo, can contribute to all somatic tissues. Using a surrogate shell culture system, the injected embryos can be manipulated and visualized easily throughout incubation. We have generated high-grade chimeras by compromising the recipient embryos and maintaining the ES cells in stage X (EG&K) recipients for a few days at 15 degrees before incubating them at 37.5 degrees. The cES system provides a novel experimental paradigm for the investigation of developmental and physiological mechanisms in the chicken.

Animals↗

High-grade transgenic somatic chimeras from chicken embryonic stem cells.

Male and female embryonic stem (ES) cell lines were derived from the area pellucidae of Stage X (EG&K) chicken embryos. These ES cell lines were grown in culture for extended periods of time and the majority of the cells retained a diploid karyotype. When reintroduced into Stage VI-X (EG&K) recipient embryos, the cES cells were able to contribute to all somatic tissues. By combining irradiation of the recipient embryo with exposure of the cES cells to the embryonic environment in diapause, a high frequency and extent of chimerism was obtained. High-grade chimeras, indistinguishable from the donor phenotype by feather pigmentation, were produced. A transgene encoding GFP was incorporated into the genome of cES cells under control of the ubiquitous promoter CX and GFP was widely expressed in somatic tissues. Although cES cells made extensive contributions to the somatic tissues, contribution to the germline was not observed.

Animals↗