Phosphatidylcholines (PCs) and γ-glutamylalanine can induce expression of type I IFN response genes. Expression of IFN-stimulated genes Ifitm3 (A) and Stat1 (B) were quantified in 32D cells stimulated with compounds of interest from the metabolomics screens proline (150 µM), PC (100 µM), orotic acid (10 µM), or γ-glutamylalanine (300 µM) for 4 hours with glycerol (0.1 mM) as the negative control and recombinant murine IFN-α2 (10 ng/mL) as the positive control. (C) Proposed model of microbiota-dependent hematopoiesis created with Biorender.com. Results are compiled from individual independent experiments normalized to their respective glycerol control for statistics (n = 3-12 technical replicates per group). Graphs show mean ± SEM, with statistical significance determined by one-way analysis of variance with Dunnett’s multiple comparison test, Kruskal-Wallis test with Dunn’s multiple comparison test (orotic acid and PC for Ifitm3), or Welch’s t test (recombinant IFN-α [rIFN-α]). *P < .05, **P < .01. γ-Ga, γ-glutamylalanine.