Experimental design and representative PET/CT scans. (A) SCD and non-SCD mice were imaged at baseline, and after 1 week they were injected intravenously with LPS and ⁶⁴Cu-LLP2A. (B) In a separate set of experiments, mice were imaged at baseline, and after 1 week they were injected intravenously with LPS and either IgG isotype control or anti-P-selectin antibody plus ⁶⁴Cu-LLP2A. (C) Representative PET/CT images of SCD and non-SCD mice 24 hours after injection of ⁶⁴Cu-LLP2A at baseline and post-LPS challenge. There are distinct differences between VLA-4 expression in SCD and non-SCD mice post-LPS in the humeri and femurs (blue arrows). (D) Representative PET/CT images of SCD mice 24 hours after injection of ⁶⁴Cu-LLP2A at baseline and post-LPS with IgG control treatment or anti-P-selectin antibody treatment. Anti-P-selectin treatment mitigates signal in the humeri and femurs (blue arrows) post-LPS.