Figure 4.

Integrin αIIb Is Upregulated on LECs in Tumor-Draining LNs and Mediates Adhesion of LN LECs to Fibrinogen In Vitro

(A) Representative images and quantification of integrin αIIb immunofluorescence stainings. Each dot represents one image; n = 8 LNs/group.

(B) FACS analysis of integrin-αIIb-positive LECs in 4T1 tumor-draining LNs. n = 3 LNs/group.

(C) Representative images of integrin αIIb expression in the subcapsular sinus of a human melanoma-draining LN.

(D) FACS analysis of integrin αIIb expression on primary murine LN LECs in vitro after stimulation for 24 hr. Points represent biological replicates (n = 2–3).

(E) FACS analysis of integrin αIIb expression by LN LECs in vivo in 4T1-bearing mice on day 10 after tumor implantation in response to VEGFR-3 and IFN-γ blockage. n = 3–4 mice/group.

(F) Matrix adhesion assay of primary murine LN LECs under integrin αIIbβ3 blockage in vitro. Points represent biological replicates (n = 10).

(G) LYVE-1/fibrinogen immunofluorescence stainings of naive and tumor-draining LNs.

Statistical significance was determined by the unpaired Student’s t test (A, B, D [each group compared to the unstimulated control] and F) and one-way ANOVA (E). Data are shown as mean with SD and differences were considered statistically significant when p < 0.05, as indicated by ^∗p < 0.05, ^∗∗p < 0.01, and ^∗∗∗p < 0.001. See also Figure S4.