Movie S1.

Profound mouse phenotype induced by ICs precedes hypothermia. FcγRIIATGN mice were injected with ICs, and the systemic response was monitored for 5 min using a score ranging from 0 to 3. All scores were observed. No perceptible phenotype was observed in FcγRIIAnull mice (second mice introduced). Mice with a score of 3 are immobilized and lethargic, and do not react to sounds or touch; a score of 2 indicates mice with impaired mobility but that still react to touch; a score of 1 corresponds to mice with slow motions and mild lethargy; and a score of 0 describes normal mice.