Curr Opin Immunol. 2025 Oct 31;98:102683. doi: 10.1016/j.coi.2025.102683. Online ahead of print.

ABSTRACT

The production of indole-3-acetic acid (IAA, auxin) is universal in microbes and plants, and contributes to human wellness, acting as an anticancer and anti-inflammatory agent. This review highlights the ubiquity of IAA production by microbes and plants, as well as its role in human health. A high-fat diet decreases IAA levels in the intestine and serum, whereas intake of IAA as part of plant or microbial-derived food, or engineering the endogenous microbiome with IAA-producing bacteria, offers suitable alternatives against diseases. The aryl hydrocarbon receptor found in immune cells in the intestine has affinities for IAA and regulates both adaptive and innate immune responses. In plants, IAA receptors are well known, as well as the molecular responses elicited. Clearly, IAA is a key molecule in plant and human health, and plant and human health are interrelated.

PMID:41175683 | DOI:10.1016/j.coi.2025.102683