Table 1:

Summary of infiltrates of PD-1 expressing cells PD-L1 expression in renal allografts at day 6.

Compartment	PD-1 cells	PD-L1 expression*
Arteries (Arcuate / Interlobular)	Prominent cuffs of PD-1+ cells surrounding arteries	Weak on endothelium; negative on smooth muscle
Glomerular Capillaries	Sporadic PD-1+ cells	Strong
Peritubular Capillaries	Diffuse interstitial infiltrate between capillaries and tubules	Negative
Proximal & Distal Tubules	Limited tubulitis that increases with PD-L1 blockade.**	Strong on basal and lateral border
Cortical Collecting system	Minor tubulitis that increases with PD-L1 blockade.	Weak

^*See Figure 2C-E

^**See Supplemental Figure S2.