CD163 and tuberculosis: CD163-expressing macrophages, which were recently shown to be highly abundant in sarcoidosis pulmonary granulomas but not in TB granulomas (43), do not accumulate lipids (50) and therefore their presence in sarcoidosis may explain why sarcoidosis granulomas are “non-caseating.” Examination of TB granulomas from infected macaques similarly revealed an absence of CD163 expression in caseating central cores of these structures containing lipid-filled macrophages (51).