Extended Data Fig. 1: The reactive lymph node resists swelling.
From: Multitier mechanics control stromal adaptations in the swelling lymph node
(a) Side view focus-stack of a homeostatic (day 0) and inflamed (day 14) popliteal lymph node (LN) from wild-type (WT) mice. Scale bar = 500 µm. (b) Quantification of LN volumes in homeostasis (day 0) and inflammation (day 2, 4, 8 and 14) from wild-type mice (n = 8, 11, 8, 9, 10). (c) Relation between volumes and corresponding measured weights of LNs as in a. A regression line is fitted. (d) Stress relaxation curves of homeostatic (day 0) and inflamed (day 2, 4, 8 and 14) LNs (n = 6, 6, 6, 6, 6). (e) Schematic representation of the generalized Kelvin model used to derive the effective resistance, viscosity and Young’s modulus from stress relaxation experiments on explanted popliteal LNs from wild-type mice in homeostasis (day 0) and inflammation (day 2, 4, 8 and 14). Adapted from Forgacs et al.26 (f) Schematic illustration and description of the short-, medium- and long-term relaxation events in a LN during a stress relaxation experiment. (g) Scanning electron microscopy image of packed lymphocytes in the homeostatic (day 0) LN paracortex of a wild-type mouse. Scale bar = 2 µm. (h, i) Quantification of (h; left, i; left) viscosity (n = 11, 9 and n = 11, 9) and (h; right, i; right) Young’s modulus (n = 13, 16, 8, 11) and (n = 13, 16, 8, 11), respectively, of stress relaxation measurements in (h) LNs of wild-type (WT) mice in homeostasis (day 0) and in (i) LNs of wild-type or OT-II mice during inflammation (day 4) following treatment with PBS or CD62L Ab (i.v. injected 24 h before measurements for homeostasis or at immunization for inflammation). Data from b, d, h, i shown as mean ± s.e.m. Datapoints in b, d, h, i represent independently measured LNs. Statistical analysis was performed using one-way ANOVA (b), unpaired two-tailed t test (h) and two-way ANOVA (i; y=Ln(y) transformed). All experiments were repeated independently (≥5 mice and ≥3 experiments). For statistical details see Supplementary Information, table 1. NS, not significant. *P < 0.05, **P < 0.01, ****P < 0.0001.
