Monitoring CD169 expression in rectal tissues from macaques infected with SIVwt vs. SIVΔNef revealed that while expression tended to be higher within 6–8 weeks following both SIVwt and SIVΔNef infections (and was not different between SIVwt and SIVΔNef), expression continued to increase during chronic infection only in SIVwt-infected animals (Fig 8A). The gene discussed is SIGLEC1; the disease is infection.