For statistical analysis of survival data, the log-rank and Gehan-Breslow Wilcoxon test was used and involved over 40 C57Bl/6 and 40 AMCase2/2 mice. Acute (0-14 days) and chronic deaths (.14days) were analyzed individually. For all other data, an unpaired, two-tailed Student's t test, or ANOVA test with a 95% confidence interval was used (Prism; GraphPad Software, Inc., La Jolla, CA). All data are represented as means 6 SEM. Figure S3 AAMØ associated with cyst lysis. Confocal fluorescence microscopy of 20 mm brain slices taken from mice at 4 weeks post infection. Imunohistochemical analysis of alternatively activated macrophage (Iba-1, red) as judged by its expression of stabilin-1 (green), adhering closely to a large round cyst. Polarized, to the site of macrophage 'attachment', bradyzoites are seen escaping in an organized fashion towards or into the AAMØ (arrows). (TIF) Figure S4 Chitinase activity is dependent on the presence of chitin and is independent of IL-4 activation. A) Bone marrow derived macrophages were analyzed for chitinase activity. Macrophages were cultured with whole cysts, cysts treated with trichoderma chitinase or media alone. Data are representative of at least 2 individual experiments with a minimum of n = 3 and are represented as mean 6 SEM. B) qRT-PCR was conducted on BMNC to measure YM-1, YM-2, RELM-a, BRP39, IL-4 and IL4Ra. Data are presented as fold increase over naïve. (TIF) Figure S5 AMCase activity associated with cyst. Confocal fluorescence microscopy of 20 mm brain slices taken from mice at 4 weeks post infection. Immunohistochemical analysis of macrophage (Iba-1, green) and AMCase (red), arrows point to AMCase polarized to the cyst wall. (TIF) Figure S6 AMCase2/2 polarization and infection studies. BMDM from WT and AMCase2/2 mice were polarized to A) M2 and B) M1 phenotype as measured by Urea and Greiss assays respectively. C57Bl/6 (WT) and AMCase2/2 mice were infected with the Me49 strain of T. gondii and sacrificed at C) 3 weeks for cyst counts and D) 5 weeks following infection. RNA was isolated from infected brains, reverse transcribed, and the resulting cDNA was analyzed for SAG1, SAG4, and MAG1 transcript levels using qRT-PCR to measure gene expression from tachyzoites, bradyzoites and cysts, respectively. Results are shown as absolute quantitation of copy number using standard curve. Data are representative of at least 3 individual experiments with a minimum of n = 3 and are represented as mean 6 SEM, ** p,0.01, *** p,0.001. (TIF) Figure S7 BALB/c macrophages lyse cysts more quickly than C57Bl/6 macrophages. BMDM from BALB/c and C57Bl/6 mice were cultured with cysts and imaged using an HT pathway microscope for 16 hours. Images were collected every 10 minutes and cyst survival time was calculated. (TIF) Video S1 3D colocalization of AMCase-secreting macrophages and parasite cysts. Three dimensional z-plane progression of 20 mm confocal image taken from mice at 4 weeks post infection. Green: tomato lectin labeling macrophages; red: AmCase; blue: DAPI labeling nuclei; white: anti-Toxoplasma. (MOV) Video S2 Cysts do not lyse in the absence of macrophages. 14 hour time-lapse movie of cysts cultured in the absence of BMDM. Images were collected every 10 minutes and movies were compiled using ImageJ. (MOV) Video S3 Rupture of T. gondii cysts in the presence of chitinase. 14 hour time-lapse movie of cysts co-cultured with WT BMDM and pretreated with 10 mg/ml trichoderma chitinase. Images were collected every 10 minutes and movies were compiled using ImageJ.