Figure 6.

Coinjection of CXCL13 and CCL21 into orthotopic tumors. (A) Correlation of CD19⁺ B cell density with TLS density in orthotopic pancreatic tumors. The dotted line represents the cutoff of minimal B cell density needed to induce lymphoneogenesis. Pink circles represent lymphoid aggregate (LA)^– PBS-treated mice, red circles represent LA⁺ PBS-treated mice, blue circles represent TLS⁺ CXCL13/CCL21-treated mice, empty blue circles represent stress-induced LA⁺ CXCL13/CCL21-treated mice. Spearman r = 0.79, P < .0001. (B–G) Flow cytometric analysis, in LA^+/– tumors from PBS-treated mice (n = 12) and TLS^+/– tumors from CXCL13/CCL21-treated mice (n = 16), of (B) CD19⁺ B cells out of CD45⁺ cells, (C) CD3⁺ T cells out of CD45⁺ cells, (D) CD4⁺ helper T cells out of CD3⁺ T cells, (E) CD8⁺ cytotoxic T cells out of CD3⁺ T cells, (F) FOXP3⁺ regulatory T cells out of CD4⁺CD3⁺ T cells, and (G) CD11b⁺ myeloid cells out of CD45⁺ cells. The mean percentage of CD19⁺ cells out of CD45⁺ cells within the PBS-treated group used to identify stress-induced lymphoid aggregates from potential chemokine-induced TLSs (dotted line in A). (H) Tumor weight in CXCL13/CCL21 intratumoral single or coinjected compared with PBS-treated mice. Each data point represents 1 mouse. Empty circles in CXCL13/CCL21 treated mice represent stress-induced lymphoid aggregates. Two-sample Kolmogorov-Smirnov test. ∗P < .05. ns, not significant.