Severe illness in LCMV_cl13-infected SAP^– mice. Body weight was tracked for SAP^– (○) and SAP⁺ mice (•) infected with LCMV_cl13, versus uninfected controls (▪). Data are presented as percentage of body weight on day 0 of infection. More severe illness was observed in SAP^– mice. Three months after infection, SAP^– mice weighed 30% less than wild-type mice (P < .002). SAP^–, n = 8; wild-type B6 (WT), n = 3. Data are representative of 3 independent experiments.