The influence of mouse strain and housing on the immune response

Five strains of mice housed individually (one per cage) or in a group (five per cage) were immunized with sheep erythrocytes (SRBC) to determine if the major histocompatibility complex (MHC) was associated with altered immune reactivity based on housing. Individually housed mice from two strains which shared neither the H2D and H2K loci, produced more antibody forming spleen lymphocytes to SRBC than group-housed mice. Corticosterone levels were not related to the level of the immune response. Thus, genetic factors related to the MHC do not influence alteration of the immune response which occurs with differential housing conditions.