Volume 120, Issue 1, Pages 99-107 (January 2001) Interferon gamma induces enterocyte resistance against infection by the intracellular pathogen Cryptosporidium parvum  Richard C.G. Pollok, Michael J.G. Farthing, Mona Bajaj-Elliott, Ian R. Sanderson, Vincent McDonald  Gastroenterology  Volume 120, Issue 1, Pages 99-107 (January 2001) DOI: 10.1053/gast.2001.20907 Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 1 Effect of duration of IFN-γ treatment of HT-29 cells on C. parvum infection. Cells were incubated with medium containing 100 U/mL IFN-γ from between 24 hours before parasite inoculation to 19 hours after parasite inoculation. Parasites were enumerated by Giemsa staining (▩) and IFA (▩). Gastroenterology 2001 120, 99-107DOI: (10.1053/gast.2001.20907) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 2 Effect of concentration of IFN-γ on inhibition of C. parvum infection in 3 different cell lines: HT-29 (▩), Caco-2 (□), and H4 cells (■). Each cell line was incubated with medium containing 100 U/mL IFN-γ for 24 hours before parasite inoculation. Gastroenterology 2001 120, 99-107DOI: (10.1053/gast.2001.20907) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 3 Differences in expression of IFN-γ R (α-chain) in H4, Caco-2, and HT-29 cell lines determined by Western blotting. Molecular weight markers (lane 1) are 43, 80, 116, and 200 kilodaltons. The IFN-γR is located at approximately 80 kilodaltons, indicated by the arrow ([a] 200 μg/mL or [b] 100 μg/mL). Gastroenterology 2001 120, 99-107DOI: (10.1053/gast.2001.20907) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 4 The effect of blockade of the JAK/STAT pathway by the selective JAK-2 inhibitor, tyrphostin B42, on IFN-γ–mediated inhibition of C. parvum infection. HT-29 cells were incubated with medium containing 100 U/mL IFN-γ. Parasites were enumerated by IFA. Gastroenterology 2001 120, 99-107DOI: (10.1053/gast.2001.20907) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 5 Inhibition of early development of C. parvum by IFN-γ. Intracellular development was quantified 4 and 24 hours after infection in HT-29 cells cultured in the presence (▩) or absence (□) of IFN-γ. Gastroenterology 2001 120, 99-107DOI: (10.1053/gast.2001.20907) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 6 Effect of the NOS inhibition on IFN-γ–mediated inhibition of C. parvum infection. ■, IFN-γ alone (100 U/mL); □, IFN-γ and high-concentration NOS inhibitor; ●, IFN-γ and low-concentration NOS inhibitor; ▩, high-concentration NOS inhibitor alone. Gastroenterology 2001 120, 99-107DOI: (10.1053/gast.2001.20907) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 7 Effect of FeSO4 on IFN-γ–mediated inhibition of C. parvum infection. HT-29 cells were incubated with medium containing 100 U/mL IFN-γ. Gastroenterology 2001 120, 99-107DOI: (10.1053/gast.2001.20907) Copyright © 2001 American Gastroenterological Association Terms and Conditions