Immunomagnetic isolation of fetal rat gonocytes

An efficient method to obtain highly enriched populations of viable gonocytes from rat embryos at Day 18 and Day 20 postcoitum (pc) is described. Single-cell suspensions with high cell yield were obtained by a collagenase/trypsin digestion of the decapsulated testis. The gonocytes were purified by a direct immunoseparation technique, super(1-3) using magnetizable beads coated with rat anti-mouse immunoglobulin M (IgM) and a monoclonal antibody 4B6.3E10, which specifically reacted with a differentiation antigen on the fetal germ cells. super(4) Populations of 8.3 plus or minus 2.7 (x 10 super(3); 18 days pc) or 1.2 plus or minus 0.25 (x 10 super(4); 20 days pc) viable gonocytes per testis with purities of 91 plus or minus 6.5% and 92 plus or minus 4.3%, respectively, as determined by Nomarski microscopy were obtained. The cells were successfully used for culture studies and as starting material for the investigation of gene expression.