Figure 6. Two cell-derived IL-12 activity is functionally different than one-cell derived IL-12 activity.

Bone marrow chimeras were generated by reconstituting irradiated CD45.1⁺ p40^−/− mice with bone marrow cells from CD45.2⁺ p40^−/−, CD45.2⁺ p35^−/−, or CD45.1⁺CD45.2⁺ WT donor mice. Chimeric mice were infected in the footpad dermis with 10⁶ dsRed L. major parasites following reconstitution.

(A) Biweekly measurement of footpad thickness at the midline following establishment of visible lesion for p40^−/− host chimeras reconstituted with p40^−/− (circles, blue), p35^−/− (squares, green), or WT (triangles, black) through the duration of infection (p40^−/−→p40^−/−, n = 4; p35^−/−→p40^−/−, n = 6; WT→p40^−/−, n = 3).

(B) Footpad thickness at the midline of p40^−/− host chimeras reconstituted with p40^−/− (circles, blue), p35^−/− (squares, green), or WT (triangles, black) 35 days after L. major infection (unpaired t test, p40^−/−→p40^−/−, n = 4; p35^−/−→p40^−/−, n = 6; WT→p40^−/−, n = 3).

(C–H) dsRed L. major parasite quantified by limiting dilution from (C) footpad lesion, (D) dLN, (E) non-dLN (ndLN), (F) spleen, (G) liver, and (H) lung tissue of p40^−/− host chimeras reconstituted with p40^−/− (circles, blue), p35^−/− (squares, green), or WT (triangles, black) 35 days after infection (unpaired t test, p40^−/−→p40^−/−, n = 4; p35^−/−→p40^−/−, n = 6; WT→p40^−/−, n = 3).

Data in this figure are representative of two independent experiments where n refers to the number of biological replicates. All data are displayed as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. Anything not marked is considered not statistically significant.