Isoallolithocholic acid (3β-Hydroxy-5α-cholanic acid) is a bile acid metabolite and T-cell modulator with anti-inflammatory activity, associated with human immune homeostasis.

Isoallolithocholic acid (3β-Hydroxy-5α-cholanic acid) (20 μM) reduces Th17 cell differentiation by approximately 50% without affecting RORγt expression. It does not impact Th1 or Th2 cell differentiation, and its regulatory effect on Tregs is cell-type specific. Isoallolithocholic acid-dependent enhancement of FoxP3 expression requires mitoROS.[1]

Isoallolithocholic acid (0.03%; in the diet; 7 days; Segmented filamentous bacteria (SFB)-colonized Jax-B6 mice) was insufficient to enhance Treg percentages both at steady state and following anti-CD3 treatment alone. Significantly enhanced the Treg population in mice treated with anti-CD3 compared to the control diet in combination with 0.3% (w/w) 3-oxo-lithocholic acid (3-oxoLCA). Reduced the number of CD45.1+ T effector cells. Enhancing Treg cells in B6 mice.[1]