In a recent collaborative work (1) supervised by Pr A. Italiano and published in Nature Cancer (2), we highlighted that the presence of mature tertiary lymphoid structures (mTLS) – a structure of prominent B cell follicles and follicular dendritic cells adjoined to a CD4/CD8 T cell-containing zone – is a new predictive biomarker for response for immune checkpoint blockers.
On large series of tumor samples from three independent patient cohorts, mTLS were captured through the automated application (Ventana Discovery XT™, Roche Diagnostics) of a multiplexed immunohistofluorescence panel consisting of CD4, CD8, CD20, CD21, and CD23 markers, and multispectral image acquisition (Vectra® Polaris™, Akoya Biosciences) and analysis. Particularly, this outstanding work evidenced unique Explicyte capacities spanning from stainings to image artificial intelligence-based analysis, strongly suited to support digital pathology programs aiming at biomarker and/or novel target evaluation & identification.
Image field of mature TLS revealed by multiplexed IHF in a primary dedifferentiated liposarcoma: The mature stage of TLS was evaluated using an immunofluorescence approach multiplexing CD4, CD8, CD20, CD21 and CD23 markers. Results are representative of 540 tumors analyzed (discovery cohort, n = 328; validation cohort A, n = 131; validation cohort B, n = 81).
(1) Institut Bergonié, Institut Gustave Roussy, INSERM, Centre de Recherche des Cordeliers, and Explicyte
(2) Vanherseck et al., Nature Cancer, 2021 – Mature tertiary lymphoid structures predict immune checkpoint inhibitor efficacy in solid tumors independently of PD-L1 expression.