And for TLR4 (Bartonella quintana LPS (200 ng/ml) or culture medium as control, anti-TLR2 or control antibody (10 mg/ml), TLR9 inhibitory oligonucleotides and its negative control (25 mg/ml). After preincubation, C. gattii B5742, isolate 27 in the previous experiment, or specific TLR ligands were added, such as BTZ043 web Pam3cys or E.coli LPS (10 mg/ml and 10 ng/ml respectively] and PBMCs were incubated as described.Materials and Methods Cryptococcal strainsForty cryptococcal isolates from the CBS Fungal Biodiversity Centre (Utrecht, the Netherlands) were used in this study. These isolates were obtained from laboratory, clinical, environmental and veterinary sources. A detailed overview of the origin, sero- and AFLP genotype of these isolates is provided in Table 1. Twentythree isolates were identified as C. gattii, 5 C. neoformans var. neoformans, 5 C. neoformans var. grubii and 7 hybrids, 3 of which were interspecies order Oltipraz hybrids between C. gattii and C. neoformans var. neoformans and 4 hybrids between both C. neoformans varieties. In addition, 11 Cuban isolates were used in separate experiments, all identified as C. neoformans var grubii (Table 2). Prior to the experiments, the strains were freshly grown on Sabouraud dextrose agar plates. A suspension of each strain was prepared in sterile phosphate buffered saline (PBS), heat-killed overnight at 56uC and quantified by spectrophotometry at a wavelength of 530 nm. The suspensions were checked for fungal and bacterial growth on a Sabouraud dextrose agar plate and a blood agar plate respectively. No growth was observed after 5 days. All strains were stored at 4uC until used.Cytokine assaysTumor necrosis factor-a (TNF-a), Interleukin-1b (IL-1b), IL-6 and IL-1 receptor antagonist (IL-1Ra) concentrations were determined from the culture supernatant after 24 hours of incubation using commercially available ELISA kits (TNF-a, IL-1b and IL1Ra: R D systems, Minneapolis, MN, USA. IL-6: Sanquin,Amsterdam, the Netherlands) according to the manufacturer’s instructions. T-cell derived cytokines IL-17 and IL-22 concentrations were determined in the supernatant after 7 days of incubation using ELISA kits (R D systems). Lower detection limits were 78 pg/ml, 39 pg/ml, 15 pg/ml, 200 pg/ml, 40 pg/ml and 78 pg/ml for TNF-a, IL-1b, IL-6, IL-1Ra, IL-17 and IL-22 respectively.Ethics statementWritten informed consent of healthy donors was provided. The study was approved by the Medical Ethical Committee ArnhemNijmegen in the Netherlands.Statistical analysisResults from at least three different experiments with a range of 5? donors were pooled and analyzed using GraphPad Prism 5 software (GraphPad, San Diego, CA). Data are given as mean 6 SE. The Mann-Whitney U-test for unpaired, nonparametrical data was used to compare differences in cytokine production between two groups. The Kruskal-Wallis test with Dunn’s multiple comparison test was used when more than two groups were compared. The Wilcoxon matched-pairs signed rank test was used to analyze differences in cytokine production between inhibitors and their controls in the inhibition experiments. The level of significance was set at p,0.05.Candida strainHeat-killed Candida albicans ATCC MYA-3573 (UC 820), a well described clinical isolate, suspended in sterile PBS, was used as a positive control.Reagents and antibodiesBartonella LPS, a penta-acylated LPS which is an antagonist of TLR4-dependent signaling, was obtained as previously described [27]. An anti-TLR2 monoclonal an.And for TLR4 (Bartonella quintana LPS (200 ng/ml) or culture medium as control, anti-TLR2 or control antibody (10 mg/ml), TLR9 inhibitory oligonucleotides and its negative control (25 mg/ml). After preincubation, C. gattii B5742, isolate 27 in the previous experiment, or specific TLR ligands were added, such as Pam3cys or E.coli LPS (10 mg/ml and 10 ng/ml respectively] and PBMCs were incubated as described.Materials and Methods Cryptococcal strainsForty cryptococcal isolates from the CBS Fungal Biodiversity Centre (Utrecht, the Netherlands) were used in this study. These isolates were obtained from laboratory, clinical, environmental and veterinary sources. A detailed overview of the origin, sero- and AFLP genotype of these isolates is provided in Table 1. Twentythree isolates were identified as C. gattii, 5 C. neoformans var. neoformans, 5 C. neoformans var. grubii and 7 hybrids, 3 of which were interspecies hybrids between C. gattii and C. neoformans var. neoformans and 4 hybrids between both C. neoformans varieties. In addition, 11 Cuban isolates were used in separate experiments, all identified as C. neoformans var grubii (Table 2). Prior to the experiments, the strains were freshly grown on Sabouraud dextrose agar plates. A suspension of each strain was prepared in sterile phosphate buffered saline (PBS), heat-killed overnight at 56uC and quantified by spectrophotometry at a wavelength of 530 nm. The suspensions were checked for fungal and bacterial growth on a Sabouraud dextrose agar plate and a blood agar plate respectively. No growth was observed after 5 days. All strains were stored at 4uC until used.Cytokine assaysTumor necrosis factor-a (TNF-a), Interleukin-1b (IL-1b), IL-6 and IL-1 receptor antagonist (IL-1Ra) concentrations were determined from the culture supernatant after 24 hours of incubation using commercially available ELISA kits (TNF-a, IL-1b and IL1Ra: R D systems, Minneapolis, MN, USA. IL-6: Sanquin,Amsterdam, the Netherlands) according to the manufacturer’s instructions. T-cell derived cytokines IL-17 and IL-22 concentrations were determined in the supernatant after 7 days of incubation using ELISA kits (R D systems). Lower detection limits were 78 pg/ml, 39 pg/ml, 15 pg/ml, 200 pg/ml, 40 pg/ml and 78 pg/ml for TNF-a, IL-1b, IL-6, IL-1Ra, IL-17 and IL-22 respectively.Ethics statementWritten informed consent of healthy donors was provided. The study was approved by the Medical Ethical Committee ArnhemNijmegen in the Netherlands.Statistical analysisResults from at least three different experiments with a range of 5? donors were pooled and analyzed using GraphPad Prism 5 software (GraphPad, San Diego, CA). Data are given as mean 6 SE. The Mann-Whitney U-test for unpaired, nonparametrical data was used to compare differences in cytokine production between two groups. The Kruskal-Wallis test with Dunn’s multiple comparison test was used when more than two groups were compared. The Wilcoxon matched-pairs signed rank test was used to analyze differences in cytokine production between inhibitors and their controls in the inhibition experiments. The level of significance was set at p,0.05.Candida strainHeat-killed Candida albicans ATCC MYA-3573 (UC 820), a well described clinical isolate, suspended in sterile PBS, was used as a positive control.Reagents and antibodiesBartonella LPS, a penta-acylated LPS which is an antagonist of TLR4-dependent signaling, was obtained as previously described [27]. An anti-TLR2 monoclonal an.