EGR1 and infection: Mac_TREM2 cluster observed at pre-infection baseline was replenished to normal levels at endpoint (Fig. 3D) demonstrated enriched expression of transcripts for FOS, FosB proto-oncogene (FOSB), activating transcription factor (ATF) 3, Regulator Of G Protein Signaling64 1, Aryl hydrocarbon receptor (AHR), NFKBIZ, BTG anti-proliferation factor (BTG) 2, early growth response (EGR) 1, lamin A/C (LMNA), RasGEF domain family member 1B (RASGEF) 1B and CD69 (Fig. 4A).