NF2 and schwannoma: Cellular ‘whorls’, which are prominent features of early schwannoma lesions in this model and in human NF2 patients, exhibited concentric patterns of biomarker distribution, with Nrg1/Nrg1+ and pS6+ cells often concentrated in the central portion and even ‘bullseye’, and Tgfa+ and pNDRG+ cells at the whorl periphery (Fig. 8h, Supplementary Fig. 9C, G).