Figure 3

Characterization of tertiary lymphoid structures in breast carcinoma. Immunohistochemical detection of the indicated antigens in serial sections of breast carcinoma with extensive immune cell infiltration. Tertiary lymphoid structures with germinal center formation were detected by A) CD20+ B lymphocyte follicle comprising a network of B) CD21+ FDC, with C) CD4+ and D) CD8+ T lymphocytes in the T cell zone. E) Bcl6+ germinal center B lymphocytes and Tfh cells were also observed within the B cell follicle with surrounding F) PNAd + HEV like vessels. Positively stained antigens are shown by brown DAB staining. Magnification 100X.