Direct HLA typing by rosetting with immunomagnetic beads coated with specific antibodies

Paramagnetic monodisperse polymer beads were coated with purified human hybridoma antibodies specific for polymorphic HLA determinants. The mAb-coated beads bound specifically to cells from individuals with the relevant HLA type. The rosettes formed by beads and cells were isolated with a magnet. Rosette formation was evaluated microscopically and used as criterion for positive typing. By this rosette assay, fast and reliable HLA typing of whole blood was possible.