IMMUNOGENETIC ISOLATION OF FETAL-RAT GONOCYTES

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