LPS-induced emergency granulopoiesis requires intact MYD88-mediated TLR signaling in nonhematopoietic cells. (A) Graphical scheme depicting experimental outline to induce LPS-induced emergency granulopoiesis in mice with MYD88 expression restricted to hematopoietic (WT→Myd88^−/−) or nonhematopoietic (Myd88^−/−→WT) cells, and respective control mice (WT→WT and Myd88^−/−→Myd88^−/−). (B) Frequency and absolute number of PB CD11b⁺ cells, and (C) BM cellularity after LPS stimulation in BM chimeric and control mice. (D) Representative FACS profile showing characteristic changes in BM CD11b⁺Gr1^high mature and BM CD11b⁺Gr1^low immature neutrophils after LPS stimulation. (E) Frequencies and absolute numbers of BM CD11b⁺Gr1^high mature, (F) BM CD11b⁺Gr1^low immature neutrophils, and (G) plasma G-CSF levels in reciprocal Myd88^−/− BM chimeras upon systemic LPS injection. Black squares, PBS-injected mice; red squares, LPS-injected mice; rel., relative; abs., absolute. Data from 2 independent experiments are shown. Two-tailed Student t tests were used to assess statistical significance (*P < .05, **P < .01, ***P < .001; ns, nonsignificant).