Figure 7.

Adoptive transfer of ex vivo LPS-primed mouse and human monocytes exerts protection in recipient mice after MCAO. A, Infarct volume analysis in mice that adoptively received ex vivo PBS-treated monocytes (PBS exmono), LPS-treated (LPS; 100 ng/ml, 2 h) monocytes (LPS exmonno), or lysed LPS-treated monocytes 7 h after MCAO (LPS lysed exmono). Mice receiving ex vivo LPS-primed monocytes showed reduction of infarct volume (n = 7–8 mice/group). Statistical analysis: one-way ANOVA F_(2,19) = 4.933, p = 0.0188), followed by Bonferroni's post hoc test, *p < 0.05. B, Assessment of sensorimotor function by tape test performance revealed that mice receiving ex vivo LPS-primed monocytes had reduced latency to contact the tape on the impaired paw (contralesional side) than mice receiving PBS-treated monocytes at 3 d after MCAO (n = 13 mice/group). Statistical analysis: two-way ANOVA (interaction, F_(1,49) = 7.828, p = 0.0073; treatment, F_(1,49) = 5.915, p = 0.0187; time, F_(1,49) = 18.4, p < 0.0001) followed by Sidak's post hoc test, **p < 0.01. C, Quantification of IL-10 and Nos2 (iNOS) expression by qRT-PCR of ex vivo PBS- or LPS-treated monocytes showed upregulation of both genes 2 h after LPS treatment (n = 4/group). Statistical analysis: unpaired two-tailed Student's t test, IL-10 (t = 15.19, df = 6, ****p < 0.0001) and Nos2 (t = 16, df = 5, ****p < 0.0001). D, Infarct volume analysis in stroke mice receiving ex vivo PBS- or LPS-treated human monocytes 7 h after MCAO. LPS-primed human monocytes significantly reduced infarct volumes after MCAO compared with mice receiving PBS-primed human monocytes (n = 9–10 mice/group). Statistical analysis: unpaired two-tailed Student's t test (t = 2.267, df = 17, *p = 0.0367). E, Histology of the meninges after adoptive transfer of GFP⁺ monocytes ex vivo treated with LPS. Monocytes transferred 7 h after MCAO were recruited to the meninges, where they associated with vessels (extravascular and intravascular localization) identified by collagen IV expression. The graph shows the number of adoptively transferred monocytes (AT) that accumulated in the meninges at 48 h MCAO of mice that received either PBS or LPS ex vivo-treated GFP⁺ monocytes. No difference in the number of accumulated monocytes was found between groups (n = 4 mice/group). Statistical analysis: unpaired two-tailed Student's t test (t = 0.5148, df = 6, p = 0.6251). F, Gene expression of inflammatory molecules in the meninges of mice receiving ex vivo PBS- or LPS-primed monocytes 48 h after MCAO. Decreased Cxcl5, Csf2, Csf3, and Cxcl10 gene upregulation was observed in the meninges of mice receiving LPS-primed monocytes (n = 10–11 mice/group). Statistical analysis: unpaired two-tailed Student's t test, Cxcl5 (t = 3.6298, df = 7, *p = 0.0084); Csf2 (t = 4.4886, df = 7, *p = 0.0028); Csf3 (t = 2.6324, df = 7, *p = 0.0337), and Cxcl10 (t = 2.7547, df = 7, *p = 0.0283).