Phytohemagglutinin (PHA) causes cells from two or more preimplantation-stage mouse embryos (after removal of the zona pellucida) to adhere rapidly and firmly upon a few minutes' exposure in vitro. Adhesion is successful at room temperature, and the cells remain agglutinated after transfer to room-temperature culture medium without PHA. The incubated aggregates continue their development. After surgical transfer to pseudopregnant recipients, aggregates comprising two different cellular genotypic populations can give rise to viable allophenic mice with both cellular genotypes. PHA treatment is thus a simple substitute for temperature-induced (37°C) aggregation of mouse blastomeres in vitro, and it provides a new and efficient tool for experimental studies of mammalian development.
ASJC Scopus subject areas
- Developmental Biology