Regenerative Medicine & Cloning Process

• Médicine Régénérative et Utilisation Thérapeutique: regenerative medicine and therapeutic use.

Réalisations

• The diagram depicts the process of cloning a lamb, starting with an egg cell donor and a nucleus donor.

• An unfertilized egg cell is taken from the egg cell donor.

• The nucleus is removed from the egg cell, creating an enucleated egg cell.

• A mammary gland cell is taken from the nucleus donor.

• The nucleus is extracted from the mammary gland cell.

• The nucleus is introduced into the enucleated egg cell, resulting in a fused cell.

• The fused cell develops into an embryo.

• The embryo is implanted into a foster mother.

• A cloned lamb, genetically identical to the nucleus donor, is born.

Timeline of Developments in Regenerative Medicine

• 1950: Nuclear transfer was achieved (Briggs and King, 1952).

• 1950: The first bone marrow transfer was performed (Thomas et al., 1957).

• 1960: A functional assay for hematopoietic stem cells was developed (Till and McCulloch, 1961).

• 1960: Transfer of differentiated cell nuclei yielded viable offspring (Gurdon, 1961).

• 1960: Tritium-labeled cells were found in the adult brain (Altman, 1961).

• 1970: Localization of intestinal stem cells was identified (Cheng and Leblond, 1974).

• 1970: Epithelial cell colonies were cultured in vitro (Rheinwald and Green, 1975).

• 1970: The term "the stem cell niche" was coined (Schofield, 1978).

• 1980: Embryonic stem cells were discovered (Martin 1981; Evans and Kaufman 1981).

• 1980: Transplantation of skin grafts to patients was achieved (O'Connor et al., 1981).

• 1980: Germ line transmission of ES cells was achieved (Bradley et al., 1984).

• 1980: Molecular-based purification of hematopoietic stem cells was developed (Spangrude et al., 1988).

• 1990: Gene therapy for ADA was developed (Bordignon et al., 1995).

• 1990: Nuclear transfer in mammals was achieved.

• 1990: Grafting of fetal brain tissue to PD patients was performed (Lindvall et al., 1989).

• 2000: The hematopoietic stem cell niche was identified (Kiel et al., 2005; Katayama et al., 2006).

• 2000: IPS cells were discovered (Takahashi and Yamanaka, 2006).

• 2010: Gene correction in transplanted skin was achieved (Hirsch et al., 2017).

• 2010: Lgr5+ intestinal stem cells were discovered (Barker et al., 2007).

• 2010: ES/IPS-derived organoids were created (Eiraku et al., 2008).

• 2010: Generation of blastoids (Rivron et al., 2018).

• 2010: The CNS stem cell niche was identified (Mirzadeh et al., 2008; Shen et al., 2008; Tavazole et al., 2008).

• 2010: Intestinal organoids from Lgr5+ cells were created (Sato et al., 2009).

• 2020: IPS-derived dopaminergic neurons were grafted to PD patients (Schweizer et al., 2020).

• 2020: IPS-derived beta-cells were transplanted to diabetic patients (Ramzy et al., 2021).