Figure 5. Hematopoietic cell expression of p40 is critical for two-cell IL-12 formation.

(A) Schematic of experimental design. Bone marrow chimeras were generated by reconstituting irradiated CD45.2⁺ p35^−/− mice with bone marrow cells from CD45.1⁺ 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. 35 days after infection, tissues were harvested and restimulated for intracellular cytokine staining and flow cytometric analysis. Gating strategy used for these panels is shown in Figure S3A.

(B) Percentage of CD44^hiIFNγ⁺CD4⁺ T cells in the spleen of p35^−/− host chimeras measured 35 days after infection (p35^−/−→p35^−/−, n = 3; p40^−/−→p35^−/−, n = 3; WT→p35^−/−, n = 2).

(C) Number of CD44^hiIFNγ⁺CD4⁺ T cells in the spleen of p35^−/− host chimeras reconstituted with p35^−/− (squares, green), p40^−/− (circles, blue), or WT (triangles, black) donor bone marrow 35 days after infection (unpaired t test, p35^−/−→p35^−/−, n = 3; p40^−/−→p35^−/−, n = 3; WT→p35^−/−,n= 2 due to animal death).

(D) Same as in (B), except CD8⁺ T cells (p35^−/−→p35^−/−, n = 3; p40^−/−→p35^−/−, n = 3; WT→p35^−/−, n = 2).

(E) Same as in (C), except CD8⁺ T cells (unpaired t test, p35^−/−→p35^−/−, n = 3; p40^−/−→p35^−/−, n = 3; WT→p35^−/−, n = 2).

Data in this figure are representative of two independent experiments where n refers to the number of biological replicates. The WT groups in these experiments are limited to n = 2 due to technical reasons; however, combining the 600r chimeras (Figure S5) with the WT groups here allows us to have four groups of WT mice, and they were not significantly different in the two experiments. (C) and (E) 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.