UDP-Induced Phagocytosis and ATP-Stimulated Chemotactic Migration Are Impaired in STIM1^−/− Microglia In Vitro and In Vivo

Figure 5

In vivo behaviour of microglia in lipopolysaccharide-injected brains of wild-type and STIM1^−/− embryonic mice. (a) Two experimental sets representing microglial aggregation at the site of injection of LPS and methylene blue (MB) in WT and STIM1^−/− mice brain. No LPS injection (upper right hemisphere) and LPS-injected (lower left hemisphere) are indicated in low-magnification images of immunostaining with Iba1 antibody (A, F, K, and P; bar = 500 μm). White boxed regions are twofold magnifications ((B, D, G, I, L, N, Q, and S; bar = 50 μm) and (C, E, H, J, M, O, R, and T; bar = 10 μm)). Merged images of green Iba1-FITC and grey-DIC are shown in B–E, G–J, L–O, and Q–T; microglia are shown in green and methylene blue particles are shown in grey. Resting ramified microglia (C, H, M, and R) were identified in the noninjected hemisphere, and the stimulated amoeboid shapes of microglia engulfing methylene blue particles (E, J, O, and T) were identified only in the LPS + MB injected region. (b) Comparison of aggregated microglial numbers at the LPS injection site. The numbers of microglia at the LPS + MB injection hemisphere and noninjected hemisphere were counted. ; ; ns, no significant difference from WT mock. Data are representative of three experiments.

(a)

(b)