Insulin-Like Growth Factor-I as an Effector Element of the Cytokine IL-4 in the Development of a Leishmania major Infection

Figure 8

IGF-I expression and the effect of IGF-I on lesion development in L. major-susceptible and -resistant mouse strains. (a) The ratio of the Igf-I mRNA amount to β-actin mRNA amount in L. major-infected BALB/c (white bars) and C57BL/6 peritoneal macrophages (black bars) is shown. (b) Confocal microscopy was used to detect IGF-I expression via immunostaining with a 1 : 75 dilution of an anti-IGF-I antibody (using an Alexa Fluor 546-conjugated secondary antibody; red) and a 1 : 200 dilution of an anti-Leishmania antibody (using an Alexa Fluor 488-conjugated secondary antibody; green). DAPI (blue) was used to stain the nuclei. Images were captured using a confocal Leica LSM510 microscope with a 63x oil immersion objective. (c and d) Stationary-phase promastigotes (10⁶) that were preincubated with or without recombinant IGF-I (50 ng/mL) for 5 min were injected into the footpads of BALB/c and C57BL/6 mice, and lesion development was measured for six weeks. One representative experiment from three independent assays is shown. (ANOVA and Tukey’s tests) compared to the respective controls. ^# (ANOVA and Tukey’s tests) between BALB/c and C57BL/6.

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