FIG 2.

IAA mediates pathology through nischarin in a histamine-dependent manner. A, Ligand binding screen of histamine and IAA. B, Plasma histamine after IAA injection. *P < .05 by Student t test. Data representative of mean ± SEM for 3 to 4 animals per condition. C, Induction of anaphylaxis by IAA in WT and HDC KO mice. D, Anaphylaxis after IAA injection in W^sh mice, and W^sh mice reconstituted with WT or HDC KO BMMCs. E, Murine nischarin gene expression in PC-12 neuronal cells, RBL-2H3 mast cells, MC/9 mast cells, and BMMCs. Values above bars represent average delta Ct for nischarin versus β-actin. Relative copies of Nisch represent the number of nischarin mRNA copies per 10⁴ copies of β-actin. n = 3 individual wells for each. F, Human nischarin gene expression from cultured iPSC-neuron cells, ROSA^{KIT WT} mast cells, and cultured skin mast cells. Values above bars represent average delta Ct versus GAPDH. Relative copies of NISCH represent the number of nischarin mRNA copies per 10⁴ copies of GAPDH (n = 1–3 individual wells for each). G, Effect of efaroxan administered 30 minutes before IAA