A previous study examined the role of leukocyte integrins on pathology and survival in the naturally occurring lupus-prone mouse model, MRL/MpJ-Faslpr, which harbors a loss-of-function mutation in the cell-death receptor Fas. Contrary to the exacerbation of kidney pathology and impaired survival we observed in Lyn-/-Itgam-/- mice, deficiency of CD11b in MRL/MpJ-Faslpr mice conferred no pathological or clinical differences (43). Here, FAS is linked to systemic lupus erythematosus.