Rab27a Regulates Dendritic Cell Immune Tolerogenic Capacity

Dendritic cells (DCs) are known to play a crucial role in inducing immune tolerance. The major cytokine that DCs use to induce immune tolerance is IL-10. Rab27a, a small G protein, has been reported to play a significant role in the cellular output process. The aim of this study was to comprehend how Rab27a regulates the secretion of IL-10 by DCs.

DCs were purified from the intestinal tissues using flow cytometry cell sorting. The enzyme-linked immunosorbent assay was used to quantify cytokines in culture supernatant.

Our observation was that patients with food allergy (FA) had a lower level of Rab27a activation in peripheral DCs than normal controls (NC). The immune tolerogenic ability of FA DCs was defective compared to NC DCs. The data of Rab27a activation levels and the immune tolerogenic capacity of DC were found to have a positive correlation. The activation of Rab27a in DCs was regulated by MADD in a significant way. Rab27a that was activated created a complex with IL-10, which was responsible for transporting IL-10 out of DCs. MADD and Rab27a activation were found to be lower in DCs collected from patients with FA. Re-establishment of MADD expression could restore the immune tolerogenic capacity of FA DCs.

Activated Rab27a is required for the release of IL-10 from DCs. MADD plays a crucial role in Rab27a activation.