A quick procedure for identifying doubly homozygous immunodeficient scid beige mice

Abstract This article describes a rapid and reliable procedure for identifying mice which are doubly homozygous at the scid and beige (bg) loci starting from CB17 scid (no T and B cells) and B6 bg mice (no NK activity). The [ Scid, bg ] mice are directly identified in the F2 progeny by monitoring (1) the hypogammaglobulinemia for the scid gene and (2) the prolonged bleeding associated with the bg gene. Like CB17 scid mice, the [ scid, bg ] mice show a high susceptibility to infections and die early in life unless they are protected against potential infections. This is achieved by a graft of splenocytes plus bone marrow cells from (B6 bg × CB17 scid ) F1 mice. These [ scid, bg ] mice combine the bg and scid immunodeficiencies and should be better recipients for xenografts than classical scid mice.