Simplified method of identifying severe combined immunodeficient (SCID) mice versus non-SCID mice by flow cytometric analysis of peripheral blood.

Abstract

Several studies have utilized simple breeding strategies to create new immunodeficient mouse strains from severe combined immunodeficient (SCID) mice and non-SCID mice with secondary traits in order to evaluate the involvement of lymphocytes and immune responses in a variety of processes. We utilized a breeding strategy with C.B-17scid/scid (SCID) (H-2d) mice and SJL (H-2s) mice to generate immunodeficient mice that were histocompatible with the inbred SJL strain (H-2s) in order to evaluate the role of histocompatible recipient lymphocytes in adoptively transferred autoimmune disease mediated by SJL T lymphocytes. [SCID x SJL]F1 mice (heterozygous for H-2 loci and heterozygous for the SCID mutation) were backcrossed with SCID mice and the resulting offspring expressed a variety of phenotypes, including SCID or non-SCID and H-2s/H-2d or H-2d/H-2d. In order to screen offspring for the desired phenotype (SCID, H-2s), a flow cytometric method utilizing forward- and side-scatter parameters of peripheral blood cells was used to distinguish SCID from non-SCID animals. This method simplified the screening process and was as reliable as anti-CD3 fluorescent monoclonal antibody staining for detecting the presence (non-SCID) or absence (SCID) of T lymphocytes in peripheral blood.