HMOX1 and infection: Finally, Luciferase assay with wild-type, or truncated promoter constructs: Site A-/- (−4/−635) and Site B-/- (−636/−1377) in the presence of LD-R and LD-S infection, further confirmed specific interaction of p50/c-Rel with Site A of HO-1 promoter resulting in its specific upregulating in LD-R-infected MФs (Fig 3E).