PD-L1, LAG-3 and LAG-3/PD-1 expression on tissue tumor samples
NSCLC, tumor, mlLAG-3, TNBC, CM
CPS, TUMOR, NSCLC
PD-L1 expression was determined per Agilent PD-L1 IHC 22C3 pharmDx Kit (SK00621-5) on the Agilent Link 48 autostainer. For NSCLC, tumor proportion score (TPS) was calculated as per manual interpretation; for EOC and TNBC, combined positive score (CPS) was calculated as follows: number of PD-L1IHC of LAG-3 was performed on 4-μm formalin-fixed paraffin-embedded (FFPE) sections using the Ventana Discovery Ultra platform. Sections were deparaffinized using Discovery Wash (Ventana, 950-510) and antigens retrieved with Discovery CC1 (Ventana, 950-500). Slides were blocked for 8 min using Inhibitor CM from the Discovery ChromoMap DAB Kit (Ventana, 760-159) and incubated with anti-LAG-3 primary antibody (EPR4392(2), 0.47 µg mlLAG-3 and PD-1 dual staining was performed on 4-μm FFPE sections using the Ventana Discovery Ultra platform. Sections were deparaffinized using Discovery Wash (Ventana, 950-510) and antigens retrieved with Discovery CC1 (Ventana, 950-500). Slides were blocked for 8 min using Inhibitor CM from the Discovery ChromoMap DAB Kit (Ventana, 760-159), followed by antibody blocking with Discovery Goat Ig Block (Ventana, 760-6008) and incubated with anti-PD-1 (NAT105; Ventana, 760-4895) for 16 min at 36 °C. After incubation with Discovery anti-mouse HQ (Ventana, 760-4814) and anti-HQ HRP (Ventana, 760-4820), slides were developed using the Discovery ChromoMap DAB Kit (Ventana, 760-159) and denatured using CC2 reagent (Ventana, 950-123). Slides were blocked with Goat Ig Block (8 min) before incubation with anti-LAG-3 primary antibody (EPR4392(2), 0.47-µg ml