Figure 2

NAT changes the immune microenvironment in breast cancer patients. (A) Leukocyte infiltration of tumors from breast cancer patients by hematoxylin and eosin (H&E) staining of tissue sections pre- and post-NAT. Yellow arrows show stromal tumor-infiltrating lymphocytes (sTILs), and celeste arrows show tumor-infiltrating lymphocytes (iTILs). Images are at 40X magnification. (B) Frequency of sTILs in BCP with non-pCR or pCR pre- and post-NAT. (C) Representative IHC for CD45+  sTIL (left) staining in tumor samples pre- and post-NAT from the same individual and frequency of CD45⁺ cells (right), (D) CD3⁺ (E) CD4⁺, (F) CD8⁺, (G) CD20⁺, (H) FoxP3⁺, (I) CD68⁺ cells. In all cases, each point represents independent samples: gray circles correspond to HD, blue circles to pCR and red circles to non-pCR patients. Data are represented as the mean ± SEM. The p values were calculated using a Mann–Whitney test. *p < 0.05, **p < 0.01, ***p < 0.001.